Re: [volt-nuts] Fluke 732A Questions
Joe: A correction on the dropout voltage when the In Cal light goes out, I found my notes and it is 21 volts instead of 22 volts. The way I did this was to remove the battery pack, AC voltage and then just feed in a power supply where the battery pack would have delivered it's voltage to the back-plane mother board. Then I just reduced the voltage until the light turned off. So that means that Fluke was following the battery manufacturers specs of 5.25 volts at the end of the discharge curve. The banana jacks on the battery pack have two jobs. One is to provide a very good chassis ground to the battery pack and the other is probably to guide the pack accurately into the mother board. One other thing I have found out the hard way is that the holes in the top plate of the battery pack where the battery terminals come through are very close to the battery terminals and can short out to the chassis. I have made the holes a LOT bigger to avoid this problem. This really depends upon the brand of batteries you are using but after having to repair the regulator board I would rather be safe than sorry. I have 6 Pomona 1756-48 low thermal leads for when I need to be careful with thermals. I also have made my own low thermal(I think) using Pomona 4892 gold plated double banana plugs and Belden 9272 twisted pair twinax, using a Pomona 1825 for the ground lead. If I need single banana plugs to connect to the 732A I use Pomona 4897 gold plated. I know that this isn't the best possible low thermal because the wire is tin plated but I have looked and I can't find a good source of bare copper twisted pair shielded wire. When I am making measurements with the home made cables I just wait a few minutes for the thermals to settle down. Why Belden 9272? It was the best choice from what was available at work. From what I have seen Pomona was acquired by Fluke and makes special low thermal cables for Fluke that are not available through the Pomona catalog. When you find out from Fluke what services they offer and prices please let all of us know. Bill - Original Message - From: J. L. Trantham jlt...@att.net To: 'Discussion of precise voltage measurement' volt-nuts@febo.com Sent: Tuesday, December 31, 2013 5:13 PM Subject: Re: [volt-nuts] Fluke 732A Questions Bill, I have yet to put my 732A though it's paces but I could connect an external power supply, disconnect the AC supply and the battery module and slowly decrease the supplied voltage and see what happens when. I'll try your measurement algorithm for the battery to see when the 'IN CAL' LED goes out and what the current draws are. If the measured voltage at J10 is 27 V, then the actual battery voltage should be about 27.6 V, accounting for the diode in the circuit (unless the current draw during measurement is so low that no voltage drop occurs across the diode). I found the NIST/NBS Tech Note easily. I think if I decide to send it out for calibration, I'll use Fluke, if they still calibrate the unit. I'll call them later this week of next week to see what services/accessories they might still have available. Yes, I wound up with the 735C. It was easy to replace the NiCd battery pack and bring it 'on scale' by adjusting the 'jumpers' and the front panel adjustment. I now only have to deal with the periodic 'NO CAL' LED indication. I need to study the 732A manual then take a close look at the 735C to see how it works on it. This also brings up the question of 'low EMF cables' for accurate measurement. I have a Fluke 720A K/V Divider on the shelf that I have yet to bring out to check to see if it is operational. Another one of those 'projects' for a later time. Where would one look for 'low EMF cables' to be used in precise measurement experiments and what errors might one expect to find using Pomona gold plated Banana Plug cables (which is as good as I have at this time)? Thanks for the info. Happy New Year to all. Joe ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.
Re: [volt-nuts] Fluke 732A Questions
Just noticed the 'banana plugs' mounted on the chassis to 'align' the battery module. Duh. Makes perfect sense. Also, thanks for the Pomona recommendations. Joe -Original Message- From: volt-nuts-boun...@febo.com [mailto:volt-nuts-boun...@febo.com] On Behalf Of Bill Gold Sent: Wednesday, January 01, 2014 10:38 AM To: Discussion of precise voltage measurement Subject: Re: [volt-nuts] Fluke 732A Questions Joe: A correction on the dropout voltage when the In Cal light goes out, I found my notes and it is 21 volts instead of 22 volts. The way I did this was to remove the battery pack, AC voltage and then just feed in a power supply where the battery pack would have delivered it's voltage to the back-plane mother board. Then I just reduced the voltage until the light turned off. So that means that Fluke was following the battery manufacturers specs of 5.25 volts at the end of the discharge curve. The banana jacks on the battery pack have two jobs. One is to provide a very good chassis ground to the battery pack and the other is probably to guide the pack accurately into the mother board. One other thing I have found out the hard way is that the holes in the top plate of the battery pack where the battery terminals come through are very close to the battery terminals and can short out to the chassis. I have made the holes a LOT bigger to avoid this problem. This really depends upon the brand of batteries you are using but after having to repair the regulator board I would rather be safe than sorry. I have 6 Pomona 1756-48 low thermal leads for when I need to be careful with thermals. I also have made my own low thermal(I think) using Pomona 4892 gold plated double banana plugs and Belden 9272 twisted pair twinax, using a Pomona 1825 for the ground lead. If I need single banana plugs to connect to the 732A I use Pomona 4897 gold plated. I know that this isn't the best possible low thermal because the wire is tin plated but I have looked and I can't find a good source of bare copper twisted pair shielded wire. When I am making measurements with the home made cables I just wait a few minutes for the thermals to settle down. Why Belden 9272? It was the best choice from what was available at work. From what I have seen Pomona was acquired by Fluke and makes special low thermal cables for Fluke that are not available through the Pomona catalog. When you find out from Fluke what services they offer and prices please let all of us know. Bill - Original Message - From: J. L. Trantham jlt...@att.net To: 'Discussion of precise voltage measurement' volt-nuts@febo.com Sent: Tuesday, December 31, 2013 5:13 PM Subject: Re: [volt-nuts] Fluke 732A Questions Bill, I have yet to put my 732A though it's paces but I could connect an external power supply, disconnect the AC supply and the battery module and slowly decrease the supplied voltage and see what happens when. I'll try your measurement algorithm for the battery to see when the 'IN CAL' LED goes out and what the current draws are. If the measured voltage at J10 is 27 V, then the actual battery voltage should be about 27.6 V, accounting for the diode in the circuit (unless the current draw during measurement is so low that no voltage drop occurs across the diode). I found the NIST/NBS Tech Note easily. I think if I decide to send it out for calibration, I'll use Fluke, if they still calibrate the unit. I'll call them later this week of next week to see what services/accessories they might still have available. Yes, I wound up with the 735C. It was easy to replace the NiCd battery pack and bring it 'on scale' by adjusting the 'jumpers' and the front panel adjustment. I now only have to deal with the periodic 'NO CAL' LED indication. I need to study the 732A manual then take a close look at the 735C to see how it works on it. This also brings up the question of 'low EMF cables' for accurate measurement. I have a Fluke 720A K/V Divider on the shelf that I have yet to bring out to check to see if it is operational. Another one of those 'projects' for a later time. Where would one look for 'low EMF cables' to be used in precise measurement experiments and what errors might one expect to find using Pomona gold plated Banana Plug cables (which is as good as I have at this time)? Thanks for the info. Happy New Year to all. Joe ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there. ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.
Re: [volt-nuts] Fluke 732A Questions
Charles, I would like to find the mating plug for J10 for several reasons, being able to get it to calibration being just one of them. However, I was hoping it would be good enough to make it to calibration on the internal batteries. I seem to recall reading that the internal batteries were good for a few hours but nothing like what the 732B would do, which sounded like the 732B could make the trip on the internal batteries. Where did you find the resistance of the thermistor 'as shipped'? I saw mention of being supplied to the original owner when shipped as well and I have had the top cover off and the battery module out to replace the batteries and found nothing to suggest a thermistor value. I have also lifted the top layer of insulation off the oven to move the cal-jumpers but did not see anything that suggested a thermistor value. My 'metrology level' standards are my HP 3458A's, calibrated by Agilent, and Solartron (Ametek) 7081's calibrated by Ametek. I have been thinking of getting the 732A calibrated by Fluke but I didn't know if they would still calibrate the unit. I wonder if they would have the 'as shipped' thermistor value on file for my specific serial number? I, too, read about the stability of the thermistor being the most important measurement. That was in the 'change sheets' attached to the manual on Didier's site. The 'cal-jumper' was at '40' when I got the unit. Per my 3458A, I could only get it down from about +220 uV to about +100 uV with the front panel adjustment. By moving the jumper to '20', I could only get it up to about -12 uV below 10 V by turning the adjustment all the way in the opposite direction. However, by connecting jumpers for both the '20' and '10', I was able to get it at 10 V with the front panel adjustment at about center position. I have not 'logged' any values yet but every time I go to the shop, it is about +/- 1 or 2 uV from 10 V. I do the 'AUTO CAL' on the 3458A each morning I go into the shop. I measure the resistance with a Fluke 8050A (simply because it is the closest DMM to the standard) and it is 4229 to 4230 ohms each day. Interestingly, when I got the 732A, undisturbed Fluke Calibration stickers were in place over each of the adjustments on the front panel, on a back screw on the top cover, and 'half' of a sticker on the back over the power supply module, as if the other half was lost when someone removed the battery module. Somehow, I find that comforting, given that it now seems so stable, making me think it is 'normal aging' that is responsible for the values I measured rather than a problem with the oven, etc.. IIRC, the spec is 6 ppm per year for 10 V, or 60 uV per year. I'll have to look at the power supply module to see if I can find some date codes but I suspect the unit is 25 to 30 years old. Unfortunately, there were no 'dates' on the stickers to tell when the unit was last calibrated. I was thinking of sending the 3458A's and the 732A out for calibration simultaneously and seeing what I find when they get back. I'll call Fluke and ask about their Cal services, the plug, and the shipping case/battery pack issues. Thanks everyone for very useful information. Joe -Original Message- From: volt-nuts-boun...@febo.com [mailto:volt-nuts-boun...@febo.com] On Behalf Of Charles Steinmetz Sent: Monday, December 30, 2013 11:23 PM To: Discussion of precise voltage measurement Subject: Re: [volt-nuts] Fluke 732A Questions Joe wrote: Also, how do you get your 732A calibrated? Do the batteries last long enough to ship overnight to a facility? No -- I assumed that was why you were looking for a battery connector. You install an external battery for shipment overnight. Fluke can supply a complete external battery with cable and plug ($375, last I knew), or you can make your own. I believe they can also supply a shipping container, which has a dedicated space for the Fluke external battery. (If you don't use Fluke's container, build something very sturdy with wood and padding and with handles that make it hard not to carry it and set it down right side up.) I wouldn't have anybody but Fluke calibrate a 732A. There are 3 levels of calibration, all with data, from about $700 to about $1500 (the last is calibration by Fluke's Primary Standards Lab). As far as thermistor values go, the relevant question is not what is the value in absolute terms, but rather what is the value in relation to the as manufactured value, which was provided by Fluke when the unit shipped. This had been recorded by the original owners of each of my units, and they are all within 2 ohms of the original value today. If you do not know the original value, then your original measurement is a going forward value and it cannot tell you anything about where you are in relation to the original manufactured value. The fact that you had to change cal jumpers suggests that either the oven temperature has shifted since manufacture, the reference
Re: [volt-nuts] Fluke 732A Questions
Joe Reference the thermistor value and its recorded value - I asked Fluke this question and the answer was, they did supply the individual 732A's value in written form to the original purchaser, but unfortunately they did not maintain a separate record. Roy -Original Message- From: J. L. Trantham Sent: Tuesday, December 31, 2013 1:22 PM To: 'Discussion of precise voltage measurement' Subject: Re: [volt-nuts] Fluke 732A Questions Charles, I would like to find the mating plug for J10 for several reasons, being able to get it to calibration being just one of them. However, I was hoping it would be good enough to make it to calibration on the internal batteries. I seem to recall reading that the internal batteries were good for a few hours but nothing like what the 732B would do, which sounded like the 732B could make the trip on the internal batteries. Where did you find the resistance of the thermistor 'as shipped'? I saw mention of being supplied to the original owner when shipped as well and I have had the top cover off and the battery module out to replace the batteries and found nothing to suggest a thermistor value. I have also lifted the top layer of insulation off the oven to move the cal-jumpers but did not see anything that suggested a thermistor value. My 'metrology level' standards are my HP 3458A's, calibrated by Agilent, and Solartron (Ametek) 7081's calibrated by Ametek. I have been thinking of getting the 732A calibrated by Fluke but I didn't know if they would still calibrate the unit. I wonder if they would have the 'as shipped' thermistor value on file for my specific serial number? I, too, read about the stability of the thermistor being the most important measurement. That was in the 'change sheets' attached to the manual on Didier's site. The 'cal-jumper' was at '40' when I got the unit. Per my 3458A, I could only get it down from about +220 uV to about +100 uV with the front panel adjustment. By moving the jumper to '20', I could only get it up to about -12 uV below 10 V by turning the adjustment all the way in the opposite direction. However, by connecting jumpers for both the '20' and '10', I was able to get it at 10 V with the front panel adjustment at about center position. I have not 'logged' any values yet but every time I go to the shop, it is about +/- 1 or 2 uV from 10 V. I do the 'AUTO CAL' on the 3458A each morning I go into the shop. I measure the resistance with a Fluke 8050A (simply because it is the closest DMM to the standard) and it is 4229 to 4230 ohms each day. Interestingly, when I got the 732A, undisturbed Fluke Calibration stickers were in place over each of the adjustments on the front panel, on a back screw on the top cover, and 'half' of a sticker on the back over the power supply module, as if the other half was lost when someone removed the battery module. Somehow, I find that comforting, given that it now seems so stable, making me think it is 'normal aging' that is responsible for the values I measured rather than a problem with the oven, etc.. IIRC, the spec is 6 ppm per year for 10 V, or 60 uV per year. I'll have to look at the power supply module to see if I can find some date codes but I suspect the unit is 25 to 30 years old. Unfortunately, there were no 'dates' on the stickers to tell when the unit was last calibrated. I was thinking of sending the 3458A's and the 732A out for calibration simultaneously and seeing what I find when they get back. I'll call Fluke and ask about their Cal services, the plug, and the shipping case/battery pack issues. Thanks everyone for very useful information. Joe -Original Message- From: volt-nuts-boun...@febo.com [mailto:volt-nuts-boun...@febo.com] On Behalf Of Charles Steinmetz Sent: Monday, December 30, 2013 11:23 PM To: Discussion of precise voltage measurement Subject: Re: [volt-nuts] Fluke 732A Questions Joe wrote: Also, how do you get your 732A calibrated? Do the batteries last long enough to ship overnight to a facility? No -- I assumed that was why you were looking for a battery connector. You install an external battery for shipment overnight. Fluke can supply a complete external battery with cable and plug ($375, last I knew), or you can make your own. I believe they can also supply a shipping container, which has a dedicated space for the Fluke external battery. (If you don't use Fluke's container, build something very sturdy with wood and padding and with handles that make it hard not to carry it and set it down right side up.) I wouldn't have anybody but Fluke calibrate a 732A. There are 3 levels of calibration, all with data, from about $700 to about $1500 (the last is calibration by Fluke's Primary Standards Lab). As far as thermistor values go, the relevant question is not what is the value in absolute terms, but rather what is the value in relation to the as manufactured value, which was provided by Fluke when the unit shipped. This had
Re: [volt-nuts] Fluke 732A Questions
I was afraid of that. Joe -Original Message- From: volt-nuts-boun...@febo.com [mailto:volt-nuts-boun...@febo.com] On Behalf Of R.Phillips Sent: Tuesday, December 31, 2013 7:53 AM To: Discussion of precise voltage measurement Subject: Re: [volt-nuts] Fluke 732A Questions Joe Reference the thermistor value and its recorded value - I asked Fluke this question and the answer was, they did supply the individual 732A's value in written form to the original purchaser, but unfortunately they did not maintain a separate record. Roy -Original Message- From: J. L. Trantham Sent: Tuesday, December 31, 2013 1:22 PM To: 'Discussion of precise voltage measurement' Subject: Re: [volt-nuts] Fluke 732A Questions Charles, I would like to find the mating plug for J10 for several reasons, being able to get it to calibration being just one of them. However, I was hoping it would be good enough to make it to calibration on the internal batteries. I seem to recall reading that the internal batteries were good for a few hours but nothing like what the 732B would do, which sounded like the 732B could make the trip on the internal batteries. Where did you find the resistance of the thermistor 'as shipped'? I saw mention of being supplied to the original owner when shipped as well and I have had the top cover off and the battery module out to replace the batteries and found nothing to suggest a thermistor value. I have also lifted the top layer of insulation off the oven to move the cal-jumpers but did not see anything that suggested a thermistor value. My 'metrology level' standards are my HP 3458A's, calibrated by Agilent, and Solartron (Ametek) 7081's calibrated by Ametek. I have been thinking of getting the 732A calibrated by Fluke but I didn't know if they would still calibrate the unit. I wonder if they would have the 'as shipped' thermistor value on file for my specific serial number? I, too, read about the stability of the thermistor being the most important measurement. That was in the 'change sheets' attached to the manual on Didier's site. The 'cal-jumper' was at '40' when I got the unit. Per my 3458A, I could only get it down from about +220 uV to about +100 uV with the front panel adjustment. By moving the jumper to '20', I could only get it up to about -12 uV below 10 V by turning the adjustment all the way in the opposite direction. However, by connecting jumpers for both the '20' and '10', I was able to get it at 10 V with the front panel adjustment at about center position. I have not 'logged' any values yet but every time I go to the shop, it is about +/- 1 or 2 uV from 10 V. I do the 'AUTO CAL' on the 3458A each morning I go into the shop. I measure the resistance with a Fluke 8050A (simply because it is the closest DMM to the standard) and it is 4229 to 4230 ohms each day. Interestingly, when I got the 732A, undisturbed Fluke Calibration stickers were in place over each of the adjustments on the front panel, on a back screw on the top cover, and 'half' of a sticker on the back over the power supply module, as if the other half was lost when someone removed the battery module. Somehow, I find that comforting, given that it now seems so stable, making me think it is 'normal aging' that is responsible for the values I measured rather than a problem with the oven, etc.. IIRC, the spec is 6 ppm per year for 10 V, or 60 uV per year. I'll have to look at the power supply module to see if I can find some date codes but I suspect the unit is 25 to 30 years old. Unfortunately, there were no 'dates' on the stickers to tell when the unit was last calibrated. I was thinking of sending the 3458A's and the 732A out for calibration simultaneously and seeing what I find when they get back. I'll call Fluke and ask about their Cal services, the plug, and the shipping case/battery pack issues. Thanks everyone for very useful information. Joe -Original Message- From: volt-nuts-boun...@febo.com [mailto:volt-nuts-boun...@febo.com] On Behalf Of Charles Steinmetz Sent: Monday, December 30, 2013 11:23 PM To: Discussion of precise voltage measurement Subject: Re: [volt-nuts] Fluke 732A Questions Joe wrote: Also, how do you get your 732A calibrated? Do the batteries last long enough to ship overnight to a facility? No -- I assumed that was why you were looking for a battery connector. You install an external battery for shipment overnight. Fluke can supply a complete external battery with cable and plug ($375, last I knew), or you can make your own. I believe they can also supply a shipping container, which has a dedicated space for the Fluke external battery. (If you don't use Fluke's container, build something very sturdy with wood and padding and with handles that make it hard not to carry it and set it down right side up.) I wouldn't have anybody but Fluke calibrate a 732A. There are 3 levels of calibration, all with data, from about $700 to about $1500 (the last
Re: [volt-nuts] Fluke 732A Questions
Joe, I live in Florida and searched for cal labs here that could do the job of calibrating references. Lockheed Martin in Orlando is certified, but may not have the best uncertainties. Fluke shows 0.3uV/V where LM shows 0.35uV/V. Tektronix in Orlando also offers calibration, but they ship it out and it turns out to be 0.38uV/V at the Keithley Primary Standards lab in Ohio. You would be better shipping it yourself to Fluke. I think Fluke is the best choice, but at least there are other options. Todd ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.
Re: [volt-nuts] Fluke 732A Questions
Joe wrote: Where did you find the resistance of the thermistor 'as shipped'? I saw mention of being supplied to the original owner when shipped as well It was recorded on the original factory cal certificate. I have the original certificates for two of mine. The others had rear panel stickers applied by their original owner (a cal lab). A properly working, good example should hold 0.1 ppm or better year in, year out. I've seen some that do not meet that, but lots of them do. I'm not aware of any other non-JJ standard that can match it, including most 732Bs. (Some folks think 732As are generally better than 732Bs because they are older and, thus, more stable because better aged. I think there is more to it -- many 732Bs are plenty old enough to have settled down to that level if they are ever going to, but even the older 732Bs don't, in general, seem to exhibit quite the stability of the 732As.) Best regards, Charles ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.
Re: [volt-nuts] Fluke 732A Questions
Hi, Are you guys adjusting your 732As? I have a friend that works in a large CAL lab and he told me to never adjust my 732As, just compare them. They send out their 732 Bs to Fluke but are never adjusted, just compared and sent back with current voltage reading ?? Thanks - Jeff - Original Message - From: Charles Steinmetz csteinm...@yandex.com To: Discussion of precise voltage measurement volt-nuts@febo.com Sent: Tuesday, December 31, 2013 9:56:37 AM Subject: Re: [volt-nuts] Fluke 732A Questions Joe wrote: Where did you find the resistance of the thermistor 'as shipped'? I saw mention of being supplied to the original owner when shipped as well It was recorded on the original factory cal certificate. I have the original certificates for two of mine. The others had rear panel stickers applied by their original owner (a cal lab). A properly working, good example should hold 0.1 ppm or better year in, year out. I've seen some that do not meet that, but lots of them do. I'm not aware of any other non-JJ standard that can match it, including most 732Bs. (Some folks think 732As are generally better than 732Bs because they are older and, thus, more stable because better aged. I think there is more to it -- many 732Bs are plenty old enough to have settled down to that level if they are ever going to, but even the older 732Bs don't, in general, seem to exhibit quite the stability of the 732As.) Best regards, Charles ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there. ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.
Re: [volt-nuts] Fluke 732A Questions
The obvious reason for that suggestion is the adjustment pot is likely to be noisy and is likely to introduce uncertainty. The big question that comes to my mind is if you care about that level of uncertainty, why not replace the pot with a voltage divider made of some low thermal coefficient fixed value resistors? -Chuck Harris jeffh...@comcast.net wrote: Hi, Are you guys adjusting your 732As? I have a friend that works in a large CAL lab and he told me to never adjust my 732As, just compare them. They send out their 732 Bs to Fluke but are never adjusted, just compared and sent back with current voltage reading ?? Thanks - Jeff ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.
Re: [volt-nuts] Fluke 732A Questions
Call Agilent about 3458A calibration then tell them that you really want your fluke calibrated and see what they will do for you. On Tue, Dec 31, 2013 at 3:48 PM, John Phillips john.philli...@gmail.comwrote: Any thing you do other than record the current voltage reading will introduce more uncertainty and increase drift unless you have a defect. Replacing a defective part will start the aging process over again for that part. Do not change anything if you can help it. Agilent is a good cal lab to use as well. They will run it for a few days and take readings a few different times and give you a report. Most of the time the battery is not enough to keep the box hot until they plug it in so they count on warming up a few days. Hope that helps. John On Tue, Dec 31, 2013 at 3:31 PM, Chuck Harris cfhar...@erols.com wrote: The obvious reason for that suggestion is the adjustment pot is likely to be noisy and is likely to introduce uncertainty. The big question that comes to my mind is if you care about that level of uncertainty, why not replace the pot with a voltage divider made of some low thermal coefficient fixed value resistors? -Chuck Harris jeffh...@comcast.net wrote: Hi, Are you guys adjusting your 732As? I have a friend that works in a large CAL lab and he told me to never adjust my 732As, just compare them. They send out their 732 Bs to Fluke but are never adjusted, just compared and sent back with current voltage reading ?? Thanks - Jeff ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/ mailman/listinfo/volt-nuts and follow the instructions there. -- John Phillips -- John Phillips ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.
Re: [volt-nuts] Fluke 732A Questions
Joe: The NIST notes can be downloaded from this site. https://archive.org/details/NISTTechNotes Here is the battery check paragraph. I check mine once and month and plot performance using Excel. 2-47. OPERATION ON BATTERY 2-48. Prior to operating the 732A on battery power, the following procedure should be followed. 1. Connect a voltmeter at the rear terminal POWER INPUT jack to monitor the battery voltage. 2. Note the voltage while the battery is on trickle charge (the AC PWR LED is on, but BTRY CHG off). The voltage should be around 27V. 3. Disconnect the line cord, wait 10 minutes, and then monitor the battery voltage for one-half hour. The battery package may have to be replaced if the voltage decrease by more than 0.2V during this period and the load represented by the 732A is correct ( see Section 4, Battery Discharge). 2-49. It may be advisable to perform the above procedure periodically to ensure battery backup capability is maintained. -- While the Fluke manual maintains that the battery life is 24 hours, the reality is that you can get maybe 12 to 15 hours on a fresh set of cells. I think that the engineers didn't figure on the total heater current being around 240 ma in the final design. The batteries are rated at 4 AH and some simple math says that 4/.24 = 16.67 hours to a battery voltage of 5.25 V. But the In Cal LED will turn off around 22 volts so maybe 15 hours at best. The batteries will continue to supply heater current so it might keep the +18.6 volt regulator working for a few more hours, but when the batteries are down that far it is hard to calculate remaining life. This is why there is a Fluke 732A-7003 Transport Case and Battery Charger and you can have up to 4 battery packs in the case. This gives you a total of 72 hours transport time, according to Fluke. I have seen people take a couple of 12 volt high capacity SLA and duct tape them to the top of the 732A to increase transport time. I am not too sure what the AH capacity is of the 12 volts cells. I would guess that 12 AH might do the job but I have never gone that far to figure out. The 24 hour spec is probably based upon the NIST Technical Note #1239 (Solid-State Voltage Standard Performance and design Guidelines) which recommended at least 24 hours of battery life for transport. You can get this from the same website as above. I never had to worry about this (battery life) as Fluke used to have a repair and cal facility in Milpitas, CA and I worked in Morgan Hill, CA. I would either hand carry the unit to be certified, or Fluke would pick it up and deliver it back, under power. Then Fluke decided to sell the whole operation to FLW Service Corp who finally dropped the whole operation around 2005. I also retired around that time so I didn't care to pay for all of this myself ( I was having the Company pay ). Since then I have not had a Certification of any 732A units and just relied upon the inter-comparison method to hopefully keep a reasonable value of the Volt. I have looked around the South SF Bay Area for a Cal Lab who could Certifiy one of my units and the only place I could find would be Simco in Sunnyvale. I will have to ask them what they charge for a Certitication of a 732A. The local Fluke place used to charge $500 but then that was using 732As that they had sent into Fluke in E verett WA. But then since this is just a hobby anymore I don't need, and didn't need while I was working, the full blown services and accuracy of Fluke in Everett. I guess a 732B would be a way to get all of this but who needs it right now, not me. Of course I could always get my own Josephson Junction but then I would be a real crazy Volt Nut and certifiable at the same time. I have never even heard about the Fluke 735C until I saw one on fleabay, and I assume you were the one who bought this when I saw you asking about schematics. Happy New Year Bill - Original Message - From: J. L. Trantham jlt...@att.net To: 'Discussion of precise voltage measurement' volt-nuts@febo.com Sent: Monday, December 30, 2013 6:28 PM Subject: Re: [volt-nuts] Fluke 732A Questions Bill, Sounds like you are further along in the 'volt-nut' process than I am. I'll have to chase down the NIST paper. I have been very impressed by the stability of the 732A and the 735C. Unfortunately, I don't have any documentation on the 735C and only the early manual for the 732A. I would be interested in the specifics of the battery check procedure in your manual. Unfortunately, my manual does not have a page 2-9. I note that there are two banana jacks on the front of the battery module, both black, one connected to ground and the other not connected to anything. Any idea of what
Re: [volt-nuts] Fluke 732A Questions
Any thing you do other than record the current voltage reading will introduce more uncertainty and increase drift unless you have a defect. Replacing a defective part will start the aging process over again for that part. Do not change anything if you can help it. Agilent is a good cal lab to use as well. They will run it for a few days and take readings a few different times and give you a report. Most of the time the battery is not enough to keep the box hot until they plug it in so they count on warming up a few days. Hope that helps. John On Tue, Dec 31, 2013 at 3:31 PM, Chuck Harris cfhar...@erols.com wrote: The obvious reason for that suggestion is the adjustment pot is likely to be noisy and is likely to introduce uncertainty. The big question that comes to my mind is if you care about that level of uncertainty, why not replace the pot with a voltage divider made of some low thermal coefficient fixed value resistors? -Chuck Harris jeffh...@comcast.net wrote: Hi, Are you guys adjusting your 732As? I have a friend that works in a large CAL lab and he told me to never adjust my 732As, just compare them. They send out their 732 Bs to Fluke but are never adjusted, just compared and sent back with current voltage reading ?? Thanks - Jeff ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/ mailman/listinfo/volt-nuts and follow the instructions there. -- John Phillips ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.
Re: [volt-nuts] Fluke 732A Questions
Jeff, Too late. I have already moved the jumpers and adjusted all of the front panel adjustments to achieve the desired output voltages. Since I don't have any 'historical' data about the performance of my specific unit, I will 'start from scratch' on the unit I now have. Whether to send it out for calibration or just keep it, adjusted by the 3458A, and watch from now on is the issue. I don't have enough data to decide about long term stability at this point but I am gaining valuable information about how long it will last on batteries and how to go about preparing it for shipment for calibration if I go that way. Thanks for the input. Joe -Original Message- From: volt-nuts-boun...@febo.com [mailto:volt-nuts-boun...@febo.com] On Behalf Of jeffh...@comcast.net Sent: Tuesday, December 31, 2013 5:23 PM To: Discussion of precise voltage measurement Subject: Re: [volt-nuts] Fluke 732A Questions Hi, Are you guys adjusting your 732As? I have a friend that works in a large CAL lab and he told me to never adjust my 732As, just compare them. They send out their 732 Bs to Fluke but are never adjusted, just compared and sent back with current voltage reading ?? Thanks - Jeff - Original Message - From: Charles Steinmetz csteinm...@yandex.com To: Discussion of precise voltage measurement volt-nuts@febo.com Sent: Tuesday, December 31, 2013 9:56:37 AM Subject: Re: [volt-nuts] Fluke 732A Questions Joe wrote: Where did you find the resistance of the thermistor 'as shipped'? I saw mention of being supplied to the original owner when shipped as well It was recorded on the original factory cal certificate. I have the original certificates for two of mine. The others had rear panel stickers applied by their original owner (a cal lab). A properly working, good example should hold 0.1 ppm or better year in, year out. I've seen some that do not meet that, but lots of them do. I'm not aware of any other non-JJ standard that can match it, including most 732Bs. (Some folks think 732As are generally better than 732Bs because they are older and, thus, more stable because better aged. I think there is more to it -- many 732Bs are plenty old enough to have settled down to that level if they are ever going to, but even the older 732Bs don't, in general, seem to exhibit quite the stability of the 732As.) Best regards, Charles ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there. ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there. ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.
Re: [volt-nuts] Fluke 732A Questions
Interesting thought. I love it when guys of that caliber compete. Joe -Original Message- From: volt-nuts-boun...@febo.com [mailto:volt-nuts-boun...@febo.com] On Behalf Of John Phillips Sent: Tuesday, December 31, 2013 5:51 PM To: Discussion of precise voltage measurement Subject: Re: [volt-nuts] Fluke 732A Questions Call Agilent about 3458A calibration then tell them that you really want your fluke calibrated and see what they will do for you. On Tue, Dec 31, 2013 at 3:48 PM, John Phillips john.philli...@gmail.comwrote: Any thing you do other than record the current voltage reading will introduce more uncertainty and increase drift unless you have a defect. Replacing a defective part will start the aging process over again for that part. Do not change anything if you can help it. Agilent is a good cal lab to use as well. They will run it for a few days and take readings a few different times and give you a report. Most of the time the battery is not enough to keep the box hot until they plug it in so they count on warming up a few days. Hope that helps. John On Tue, Dec 31, 2013 at 3:31 PM, Chuck Harris cfhar...@erols.com wrote: The obvious reason for that suggestion is the adjustment pot is likely to be noisy and is likely to introduce uncertainty. The big question that comes to my mind is if you care about that level of uncertainty, why not replace the pot with a voltage divider made of some low thermal coefficient fixed value resistors? -Chuck Harris jeffh...@comcast.net wrote: Hi, Are you guys adjusting your 732As? I have a friend that works in a large CAL lab and he told me to never adjust my 732As, just compare them. They send out their 732 Bs to Fluke but are never adjusted, just compared and sent back with current voltage reading ?? Thanks - Jeff ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/ mailman/listinfo/volt-nuts and follow the instructions there. -- John Phillips -- John Phillips ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there. ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.
Re: [volt-nuts] Fluke 732A Questions
Bill, I have yet to put my 732A though it's paces but I could connect an external power supply, disconnect the AC supply and the battery module and slowly decrease the supplied voltage and see what happens when. I'll try your measurement algorithm for the battery to see when the 'IN CAL' LED goes out and what the current draws are. If the measured voltage at J10 is 27 V, then the actual battery voltage should be about 27.6 V, accounting for the diode in the circuit (unless the current draw during measurement is so low that no voltage drop occurs across the diode). I found the NIST/NBS Tech Note easily. I think if I decide to send it out for calibration, I'll use Fluke, if they still calibrate the unit. I'll call them later this week of next week to see what services/accessories they might still have available. Yes, I wound up with the 735C. It was easy to replace the NiCd battery pack and bring it 'on scale' by adjusting the 'jumpers' and the front panel adjustment. I now only have to deal with the periodic 'NO CAL' LED indication. I need to study the 732A manual then take a close look at the 735C to see how it works on it. This also brings up the question of 'low EMF cables' for accurate measurement. I have a Fluke 720A K/V Divider on the shelf that I have yet to bring out to check to see if it is operational. Another one of those 'projects' for a later time. Where would one look for 'low EMF cables' to be used in precise measurement experiments and what errors might one expect to find using Pomona gold plated Banana Plug cables (which is as good as I have at this time)? Thanks for the info. Happy New Year to all. Joe -Original Message- From: volt-nuts-boun...@febo.com [mailto:volt-nuts-boun...@febo.com] On Behalf Of Bill Gold Sent: Tuesday, December 31, 2013 6:26 PM To: Discussion of precise voltage measurement Subject: Re: [volt-nuts] Fluke 732A Questions Joe: The NIST notes can be downloaded from this site. https://archive.org/details/NISTTechNotes Here is the battery check paragraph. I check mine once and month and plot performance using Excel. 2-47. OPERATION ON BATTERY 2-48. Prior to operating the 732A on battery power, the following procedure should be followed. 1. Connect a voltmeter at the rear terminal POWER INPUT jack to monitor the battery voltage. 2. Note the voltage while the battery is on trickle charge (the AC PWR LED is on, but BTRY CHG off). The voltage should be around 27V. 3. Disconnect the line cord, wait 10 minutes, and then monitor the battery voltage for one-half hour. The battery package may have to be replaced if the voltage decrease by more than 0.2V during this period and the load represented by the 732A is correct ( see Section 4, Battery Discharge). 2-49. It may be advisable to perform the above procedure periodically to ensure battery backup capability is maintained. -- While the Fluke manual maintains that the battery life is 24 hours, the reality is that you can get maybe 12 to 15 hours on a fresh set of cells. I think that the engineers didn't figure on the total heater current being around 240 ma in the final design. The batteries are rated at 4 AH and some simple math says that 4/.24 = 16.67 hours to a battery voltage of 5.25 V. But the In Cal LED will turn off around 22 volts so maybe 15 hours at best. The batteries will continue to supply heater current so it might keep the +18.6 volt regulator working for a few more hours, but when the batteries are down that far it is hard to calculate remaining life. This is why there is a Fluke 732A-7003 Transport Case and Battery Charger and you can have up to 4 battery packs in the case. This gives you a total of 72 hours transport time, according to Fluke. I have seen people take a couple of 12 volt high capacity SLA and duct tape them to the top of the 732A to increase transport time. I am not too sure what the AH capacity is of the 12 volts cells. I would guess that 12 AH might do the job but I have never gone that far to figure out. The 24 hour spec is probably based upon the NIST Technical Note #1239 (Solid-State Voltage Standard Performance and design Guidelines) which recommended at least 24 hours of battery life for transport. You can get this from the same website as above. I never had to worry about this (battery life) as Fluke used to have a repair and cal facility in Milpitas, CA and I worked in Morgan Hill, CA. I would either hand carry the unit to be certified, or Fluke would pick it up and deliver it back, under power. Then Fluke decided to sell the whole operation to FLW Service Corp who finally dropped the whole operation around 2005. I also retired around that time so I didn't care to pay for all of this myself ( I was having the Company pay ). Since then I have not had a Certification
Re: [volt-nuts] Fluke 732A Questions
Joe, I don't have any history on my 732As either. M y 3458As 2002 are out of cal too so I'm running blind with all my stuff :o) I'm hoping to find a cheap 732B and have my CAL lab buddy sneak it into work and do a poor mans cal on it. (hard to do with a 732A) He does this each year with my LN 4214 10K standards but he's getting close to retirement. I wish Fluke had a cheap cal for the hobbyist - Jeff - Original Message - From: J. L. Trantham jlt...@att.net To: Discussion of precise voltage measurement volt-nuts@febo.com Sent: Tuesday, December 31, 2013 7:01:32 PM Subject: Re: [volt-nuts] Fluke 732A Questions Jeff, Too late. I have already moved the jumpers and adjusted all of the front panel adjustments to achieve the desired output voltages. Since I don't have any 'historical' data about the performance of my specific unit, I will 'start from scratch' on the unit I now have. Whether to send it out for calibration or just keep it, adjusted by the 3458A, and watch from now on is the issue. I don't have enough data to decide about long term stability at this point but I am gaining valuable information about how long it will last on batteries and how to go about preparing it for shipment for calibration if I go that way. Thanks for the input. Joe ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.
Re: [volt-nuts] Fluke 732A Questions
Hi Todd I would appreciate a copy of your later issue manual for the 732A - please let me know when you make this available - Dider's site ? Many thanks Roy -Original Message- From: T. Micallef Sent: Monday, December 30, 2013 4:03 AM To: volt-nuts@febo.com Subject: Re: [volt-nuts] Fluke 732A Questions Joe, I don't know if it makes any difference but my manual is for the 732A/AN p/n 788414 I found a couple of brochures that I scanned and uploaded too. I forgot to mention, I have been collecting information regarding the techniques used to do intercomparisons using scanners like the Data Proof models. While searching a couple of weeks ago, I came across an old document from a Measurement Science Conference back in 1983. The document contains an article regarding the testing of the Fluke 735C. I thought you may have little to no info regarding your reference and thought I would let you know about it. The document is easy to find using google. It is named MSC1983.pdf I will upload it as well, but I was not sure if Didier wants to track conference docs. Todd ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there. ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.
Re: [volt-nuts] Fluke 732A Questions
I may be unable to move manuals until the end of the week. However, you can always download a manual that was just uploaded by using ftp. Check the Upload button on the Manuals page. Happy New Year everyone. Didier KO4BB R.Phillips phill...@btinternet.com wrote: Hi Todd I would appreciate a copy of your later issue manual for the 732A - please let me know when you make this available - Dider's site ? Many thanks Roy -Original Message- From: T. Micallef Sent: Monday, December 30, 2013 4:03 AM To: volt-nuts@febo.com Subject: Re: [volt-nuts] Fluke 732A Questions Joe, I don't know if it makes any difference but my manual is for the 732A/AN p/n 788414 I found a couple of brochures that I scanned and uploaded too. I forgot to mention, I have been collecting information regarding the techniques used to do intercomparisons using scanners like the Data Proof models. While searching a couple of weeks ago, I came across an old document from a Measurement Science Conference back in 1983. The document contains an article regarding the testing of the Fluke 735C. I thought you may have little to no info regarding your reference and thought I would let you know about it. The document is easy to find using google. It is named MSC1983.pdf I will upload it as well, but I was not sure if Didier wants to track conference docs. Todd ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there. ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there. -- Sent from my Motorola Droid Razr 4G LTE wireless tracker while I do other things. ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.
Re: [volt-nuts] Fluke 732A Questions
My manual came from manualsplus. It was in excellent condition compared to the ones on eBay. You do have to ask them for a picture of every manual since they can vary in condition. I have rescanned the whole manual, which I should have done anyway. I have two missing pages and I am hopeful the seller will scan them and forward them to me. Todd ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.
Re: [volt-nuts] Fluke 732A Questions
I called them this AM and they only had a 'copy' of the manual and not an original. If I understand what you are saying, you got a copy as well. If so, were the 'change sheets' part of the 'copy'? When I asked about that, I was told that there were no 'change sheets' in the copy she was looking at when I called and asked about condition and change sheets. Joe -Original Message- From: volt-nuts-boun...@febo.com [mailto:volt-nuts-boun...@febo.com] On Behalf Of T. Micallef Sent: Monday, December 30, 2013 1:06 PM To: volt-nuts@febo.com Subject: Re: [volt-nuts] Fluke 732A Questions My manual came from manualsplus. It was in excellent condition compared to the ones on eBay. You do have to ask them for a picture of every manual since they can vary in condition. I have rescanned the whole manual, which I should have done anyway. I have two missing pages and I am hopeful the seller will scan them and forward them to me. Todd ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there. ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.
Re: [volt-nuts] Fluke 732A Questions
Charles, I just assumed that it was obsolete. I'll contact Fluke. Thanks. Joe -Original Message- From: volt-nuts-boun...@febo.com [mailto:volt-nuts-boun...@febo.com] On Behalf Of Charles Steinmetz Sent: Monday, December 30, 2013 5:52 PM To: Discussion of precise voltage measurement Subject: Re: [volt-nuts] Fluke 732A Questions Robert wrote: As Roy has already said, this is a hypertronics connector.* * * Sorry, I don't have any, or a cheap source. The plug that mates with the jack on the back of the newer 732A battery is Fluke part number 2181497. IIRC, I paid about $10 each (some years ago) direct from Fluke. Best regards, Charles ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there. ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.
Re: [volt-nuts] Fluke 732A Questions
I received the manual with the plastic gray cover just like many of their newer manuals. It appears to have sat on a shelf with little use. No user notes have been found. The changes are part of the manual as an additional section in the back. I suspect that since it wasn't used much, no one noticed the missing pages. Even the two brochures were in immaculate condition. I am guessing that maybe their copies are from my original and are missing the pages in question (4-9 through 4-12). Since I didn't get a response from them, I will call in the morning since I am in need of another manual. Todd ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.
Re: [volt-nuts] Fluke 732A Questions
Hi Joe I also obtained a Fluke 732A back in October last, and I have fitted a new set of SLA batteries and it is working just fine - I am still very impressed by its accuracy and stability, and its build quality. First, the external 3-pin power socket is a HYPERTRONICS 'D' type connector (female) type 100-166 - but I have not found one to date ! I also expected the temperature monitoring thermistor to give a 3 to 4 K ohms, as indicated in the manual P/N 645051 dated May 1983 - but I guess that you have a later model as I do, mine being serial # 4845***, some modifications were made,and I understand that this included a change of thermistor, so the standard reading is in keeping with your result. My unit gives a very stable 4.520 K ohms, being between 4.52080 and 4.52090 K ohms. Judging by your findings, you are also using the 1983 copy of the User Manual - we could both use a more up to date issue. I am awaiting the repair of my 3458A - so I am having to rely upon a recently calibrated Keithley 2015 and my good old 3456A - but they both give very impressive results - The Keithley giving 1.07 volts for the 1 volt output, and 10.0 volts for the 10 volt output (how I miss that final digit). Looking forward to your further results and any other owners comments. Best regards Roy -Original Message- From: J. L. Trantham Sent: Saturday, December 28, 2013 10:51 PM To: volt-nuts@febo.com Subject: [volt-nuts] Fluke 732A Questions I have reviewed the prior postings on Volt-nuts (a very rewarding review, BTW)) regarding the 732A and have two questions: 1.Has anyone determined the part number, or a source, for the mating plug to J10, the external power connector for the 732A-7005 battery pack? I noted some postings recently about this but did not find a definitive response regarding the identity of this plug. The alternative would appear to be a complete replacement of J10 and its plug, as long is it all fits in the opening in the panel. I hate to 'bore holes' in vintage equipment. 2. The oven thermistor in my 'new to me' unit measures 4229 ohms (+/- an ohm or two) after the unit has warmed up for a week or so. I note the manual refers to 3K to 4K for the value of this thermistor when the unit is 'stable' as well as other's posting values in the mid 3500's ohms for their units. Should I be concerned? The unit seems to be stable to within about 2 uV over about a week (as measured by my 3458A - see below). Should I open the unit and try to measure the oven temperature or just be satisfied that the unit seems to be working? I had to replace the four 6V 4AH SLA batteries and they charged up appropriately as judged by the front panel LED's. I had to remove the 'jumper' for the '40' option on the A7 board and connect the jumper to the '20' and '10' options (total of '30') in order to get the unit to adjust to 10.000 VDC on my 'Agilent In Cal'd' 3458A. The need to change the jumpers, perhaps, could be just an ageing issue or, on the other hand, a 'temperature' issue with the oven. Should I open the unit and directly measure the temperature (supposedly about 48 degrees C) or just be satisfied with what I have? My recently added 735C also needed moving some 'jumpers' in order to get it 'on scale', as determined by my 3458A, although it's thermistor measures about 3330 ohms (after being on for several weeks). Thanks for everyone's help. Joe ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there. ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.
Re: [volt-nuts] Fluke 732A Questions
Roy, Thanks for the info. Looking at the Hypertronics catalog, it would appear that the panel mounted socket (with male, solder cup, pins) is: P/N D01EEB306MSUTH And the mating plug would be: P/N D01PB306FSUTAH However, the dimensions are a bit off and the appearance of the panel mounted socket is not the same as what is on my 732A, J10, on the back of the 732A-7005 battery module. My connector is exactly as shown in the change sheets with a dimension of 0.475 inches side to side and 0.500 inches top to bottom (as viewed from the back of the unit) rather than 0.512 x 0.512 as suggested in the catalog. However, the diameter of the mounting hole and the presence of a 'notch' appears to be as shown in the catalog, thus suggesting that it, indeed, is a series D01 part. The diameter of the threaded part of J10 is 0.410 inches and the catalog calls for a hole diameter of 0.441 inches. One other observation is the presence of a 'symbol' on the bottom edge of the socket (as viewed from below) that looks like a stylized 'FRE', The 'F' perhaps could be an 'A' and the 'E' perhaps could be a 'B'. The symbol starts low and ends low with a 'peak' of the symbol in the middle of the 'R', sort of a 'roof' shape to the top of the symbol and flat on the bottom of the symbol. Not sure what that means but I have a picture of it if anyone thinks it would help. It does not look like the stylized 'H' symbol shown in the Hpertronic catalog. Perhaps the company was something else before they became Hypertronics. I looked through the change sheets for the 732A and could find no mention of the value of the thermistor resistance at temperature, only comments about what its stability should be. Knowing that you have a value in the mid 4K range is reassuring. My S/N starts with 3. Right now, it indicates 10.005 VDC on the 3458A and 4230 ohms on the Fluke 8050A. Thanks for your help. Joe -Original Message- From: volt-nuts-boun...@febo.com [mailto:volt-nuts-boun...@febo.com] On Behalf Of R.Phillips Sent: Sunday, December 29, 2013 8:40 AM To: Discussion of precise voltage measurement Subject: Re: [volt-nuts] Fluke 732A Questions Hi Joe I also obtained a Fluke 732A back in October last, and I have fitted a new set of SLA batteries and it is working just fine - I am still very impressed by its accuracy and stability, and its build quality. First, the external 3-pin power socket is a HYPERTRONICS 'D' type connector (female) type 100-166 - but I have not found one to date ! I also expected the temperature monitoring thermistor to give a 3 to 4 K ohms, as indicated in the manual P/N 645051 dated May 1983 - but I guess that you have a later model as I do, mine being serial # 4845***, some modifications were made,and I understand that this included a change of thermistor, so the standard reading is in keeping with your result. My unit gives a very stable 4.520 K ohms, being between 4.52080 and 4.52090 K ohms. Judging by your findings, you are also using the 1983 copy of the User Manual - we could both use a more up to date issue. I am awaiting the repair of my 3458A - so I am having to rely upon a recently calibrated Keithley 2015 and my good old 3456A - but they both give very impressive results - The Keithley giving 1.07 volts for the 1 volt output, and 10.0 volts for the 10 volt output (how I miss that final digit). Looking forward to your further results and any other owners comments. Best regards Roy -Original Message- From: J. L. Trantham Sent: Saturday, December 28, 2013 10:51 PM To: volt-nuts@febo.com Subject: [volt-nuts] Fluke 732A Questions I have reviewed the prior postings on Volt-nuts (a very rewarding review, BTW)) regarding the 732A and have two questions: 1.Has anyone determined the part number, or a source, for the mating plug to J10, the external power connector for the 732A-7005 battery pack? I noted some postings recently about this but did not find a definitive response regarding the identity of this plug. The alternative would appear to be a complete replacement of J10 and its plug, as long is it all fits in the opening in the panel. I hate to 'bore holes' in vintage equipment. 2. The oven thermistor in my 'new to me' unit measures 4229 ohms (+/- an ohm or two) after the unit has warmed up for a week or so. I note the manual refers to 3K to 4K for the value of this thermistor when the unit is 'stable' as well as other's posting values in the mid 3500's ohms for their units. Should I be concerned? The unit seems to be stable to within about 2 uV over about a week (as measured by my 3458A - see below). Should I open the unit and try to measure the oven temperature or just be satisfied that the unit seems to be working? I had to replace the four 6V 4AH SLA batteries and they charged up appropriately as judged by the front panel LED's. I had to remove the 'jumper' for the '40' option on the A7 board and connect the jumper to the '20
Re: [volt-nuts] Fluke 732A Questions
Hi Joe, As Roy has already said, this is a hypertronics connector. I've had one other piece of equipment with this type of connector, a nitrogen laser. See http://www.thinksrs.com/products/NL100.htm The downloadable user manual has details. Sorry, I don't have any, or a cheap source. Robert G8RPI. From: J. L. Trantham jlt...@att.net To: volt-nuts@febo.com Sent: Saturday, 28 December 2013, 22:51 Subject: [volt-nuts] Fluke 732A Questions I have reviewed the prior postings on Volt-nuts (a very rewarding review, BTW)) regarding the 732A and have two questions: 1. Has anyone determined the part number, or a source, for the mating plug to J10, the external power connector for the 732A-7005 battery pack? I noted some postings recently about this but did not find a definitive response regarding the identity of this plug. The alternative would appear to be a complete replacement of J10 and its plug, as long is it all fits in the opening in the panel. I hate to 'bore holes' in vintage equipment. 2. The oven thermistor in my 'new to me' unit measures 4229 ohms (+/- an ohm or two) after the unit has warmed up for a week or so. I note the manual refers to 3K to 4K for the value of this thermistor when the unit is 'stable' as well as other's posting values in the mid 3500's ohms for their units. Should I be concerned? The unit seems to be stable to within about 2 uV over about a week (as measured by my 3458A - see below). Should I open the unit and try to measure the oven temperature or just be satisfied that the unit seems to be working? I had to replace the four 6V 4AH SLA batteries and they charged up appropriately as judged by the front panel LED's. I had to remove the 'jumper' for the '40' option on the A7 board and connect the jumper to the '20' and '10' options (total of '30') in order to get the unit to adjust to 10.000 VDC on my 'Agilent In Cal'd' 3458A. The need to change the jumpers, perhaps, could be just an ageing issue or, on the other hand, a 'temperature' issue with the oven. Should I open the unit and directly measure the temperature (supposedly about 48 degrees C) or just be satisfied with what I have? My recently added 735C also needed moving some 'jumpers' in order to get it 'on scale', as determined by my 3458A, although it's thermistor measures about 3330 ohms (after being on for several weeks). Thanks for everyone's help. Joe ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there. ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.
Re: [volt-nuts] Fluke 732A Questions
Joe, I have the external battery pack (732A-7003) that I picked up a while ago. It is indeed the D01 connector. It is printed clearly on the outside edge along with the three letters that look like ARB. The company's website states they are now owned by Smiths Connectors and the connector is part of Hypertac. No list of distributors was found on the website. I found a seller Astrex Electronics, but they do not have a price listed for the female version, just the male. I searched for D01P306FSTAH. This is the female plug with solder cups. To date, I have reconditioned three 732A's and they have been operating fine with little issues, except when I lost power for an extended time and two batteries in one of the packs died. All four were replaced and they have been working fine. The two older 732A's have thermistor values in the 3k-4k range. The newer unit (based on the newer heater rev) is around 4.25K. All three had their potentiometers changed on the regulator and pre-regulator boards. The datecodes on all appeared to be from 1985. The parts list must have been updated as some of the pots did not have the same value as the ones installed. I cannot remember which ones were different. I did not see a mention in the change/errata. Also, I had to remove the reference ovens to repair broken 10V potentiometers, as someone had broken one (free spinning) and another unit appeared to have a noisy wiper so it was replaced as well. The 1V and 1.018V pots were not changed. The third 10V pot was replaced because I had success with the other two and it was much easier the third time around. The jumpers on the all the A7 boards were adjusted. I highly recommend checking the inline fuse to the heater if you suspect it is not working. You can find it tucked inside behind the oven. It should be covered in heat shrink. Lastly, there was a rev done that does not appear in the downloadable users manual on Didier's website. It appears the heaters were separated into two groups of two instead of one group of four. Some of the parts were mounted under the oven assembly on the A8 Preheater PCA. If you look at the A4 board from the top, you will see either one or two transistors mounted to the frame (Q4,Q14). If you see only one (Q4), chances are you have the newer rev. I bought the manual recently and just noticed these revs were in my book. I will try and scan the extra info and upload them. Todd ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.
Re: [volt-nuts] Fluke 732A Questions
Todd, Very good information. Sounds like we are getting close to the correct P/N for the mating plug for the socket. My 732A has only a single transistor mounted to the frame from the A4 Regulator Assembly, in the position of Q4, and the resistance is 4230 ohms after the unit is 'warmed up' and stable. I recently bought a manual as well but it did not have any 'update sheets'. I would love to have a copy of your 'update sheets'. I did a 'clean up' of the update sheets on Didier's site and can send them to anyone that wants one. I printed the .PDF from the Fluke site and added the 'cleaned up' version of the update sheets and it makes a very nice manual. I would love to add the other sheets to this. I also have a 735C that is very similar to the 732A but lot's of mechanical differences. It has two transistors on the Regulator Assembly, presumably A4 and Q4 and Q14. I do not have a manual for the 735C. It's thermistor value is in the mid 3K range. It, too, is very stable and has many similarities to the 732A but has recently developed a 'new problem'. The 'NO CAL' LED comes on after a few days for no apparent reason. I need to open it up again and take a look at that circuit to see what the problem is. On the 732A, the 'IN CAL' LED is continuously lighted when there has been no power interruption. On the 735C, the 'NO CAL' LED illuminates when power is restored after a power failure. I replaced the NiCd battery pack and all seems to be well but the 'NO CAL' LED comes on after having been reset (by inserting a copper wire in the 'adjust' opening). I wonder if my 'reset' process is the problem. On the 732A, you connect to the negative terminal then touch the 'pad' inside the 'RESET' opening. There is no such 'RESET' opening on the 735C. Just placing the wire (that I use to adjust the 10 V adjustment) inside the adjustment opening and aiming to the side would reset the LED. Happy to help with the scanning of the manual and update sheets if needed. Thanks again for the info. Joe -Original Message- From: volt-nuts-boun...@febo.com [mailto:volt-nuts-boun...@febo.com] On Behalf Of T. Micallef Sent: Sunday, December 29, 2013 6:05 PM To: volt-nuts@febo.com Subject: Re: [volt-nuts] Fluke 732A Questions Joe, I have the external battery pack (732A-7003) that I picked up a while ago. It is indeed the D01 connector. It is printed clearly on the outside edge along with the three letters that look like ARB. The company's website states they are now owned by Smiths Connectors and the connector is part of Hypertac. No list of distributors was found on the website. I found a seller Astrex Electronics, but they do not have a price listed for the female version, just the male. I searched for D01P306FSTAH. This is the female plug with solder cups. To date, I have reconditioned three 732A's and they have been operating fine with little issues, except when I lost power for an extended time and two batteries in one of the packs died. All four were replaced and they have been working fine. The two older 732A's have thermistor values in the 3k-4k range. The newer unit (based on the newer heater rev) is around 4.25K. All three had their potentiometers changed on the regulator and pre-regulator boards. The datecodes on all appeared to be from 1985. The parts list must have been updated as some of the pots did not have the same value as the ones installed. I cannot remember which ones were different. I did not see a mention in the change/errata. Also, I had to remove the reference ovens to repair broken 10V potentiometers, as someone had broken one (free spinning) and another unit appeared to have a noisy wiper so it was replaced as well. The 1V and 1.018V pots were not changed. The third 10V pot was replaced because I had success with the other two and it was much easier the third time around. The jumpers on the all the A7 boards were adjusted. I highly recommend checking the inline fuse to the heater if you suspect it is not working. You can find it tucked inside behind the oven. It should be covered in heat shrink. Lastly, there was a rev done that does not appear in the downloadable users manual on Didier's website. It appears the heaters were separated into two groups of two instead of one group of four. Some of the parts were mounted under the oven assembly on the A8 Preheater PCA. If you look at the A4 board from the top, you will see either one or two transistors mounted to the frame (Q4,Q14). If you see only one (Q4), chances are you have the newer rev. I bought the manual recently and just noticed these revs were in my book. I will try and scan the extra info and upload them. Todd ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there. ___ volt-nuts mailing list -- volt-nuts
Re: [volt-nuts] Fluke 732A Questions
Joe, I don't know if it makes any difference but my manual is for the 732A/AN p/n 788414 I found a couple of brochures that I scanned and uploaded too. I forgot to mention, I have been collecting information regarding the techniques used to do intercomparisons using scanners like the Data Proof models. While searching a couple of weeks ago, I came across an old document from a Measurement Science Conference back in 1983. The document contains an article regarding the testing of the Fluke 735C. I thought you may have little to no info regarding your reference and thought I would let you know about it. The document is easy to find using google. It is named MSC1983.pdf I will upload it as well, but I was not sure if Didier wants to track conference docs. Todd ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.
