RE: radar
There are even better systems on the market. The German police use systems which show the driver very clearly by placing the cameras so, that it takes the front of the car. So please smile if you drive too fast Best Regards Lothar Schmidt Technical Manager EMC/Radio BQB CETECOM Inc. 411 Dixon Landing Road Milpitas, CA 95035 * +1 408 586 6214 * +1 408 586 6299 -Original Message- From: kazimier_gawrzy...@dell.com [mailto:kazimier_gawrzy...@dell.com] Sent: Tuesday, January 08, 2002 1:09 PM To: ghery.pet...@intel.com; nickjro...@cs.com; emc-p...@majordomo.ieee.org Subject: RE: radar My own experience with photo radar showed a very clear picture of the rear of the car, showing the license plate and also a good view of the back of my head. No court summons was involved as I did not attempt to fight it. The ticket went out to the registered owner of the vehicle...not the driver hence no insurance impact. My two cent and and not that of my employer, Regards, Kaz Gawrzyjal Dell -Original Message- From: Pettit, Ghery [mailto:ghery.pet...@intel.com] Sent: Tuesday, January 08, 2002 2:34 PM To: 'Nick Rouse'; emc Subject: RE: radar Does the photo show who was driving the car? Can't say that I would be too happy to be summoned to court when one of my kids (or wife) was speeding. Ghery Pettit -Original Message- From: Nick Rouse [mailto:nickjro...@cs.com] Sent: Tuesday, January 08, 2002 12:03 PM To: emc Subject: Re: radar I don't know if the technique is used in America but the speed cameras in the UK are triggered by radar but produce evidence by taking two pictures illuminated by two strobe pulses timed about 150ms apart. Stripes are painted across the road spaced so that between flashes a vehicle will traverse one stripe pitch for every 10mph.If the pictures show you have traversed more than 7 stripe pitches (on motorways)you will receive copies of these photos together with a summons to appear in court. Nick Rouse Jim Freeman wrote: Hi All, I apologize for being off subject but I was driving to work and noticed aCalifornia Highway Patrol officer on the opposite of the freeway an about 500 yards away. What brought him to my attention was what appeared to be a strobe light that was flashing. I have been thinking about and I was wondering if the new radar has some ways of taking pictures or if the strobe light really is the radar source. Any help would be appreciated. Thanks Jim Freeman Hi All, I apologize for being off subject but I was driving to work and noticed aCalifornia Highway Patrol officer on the opposite of the freeway an about 500 yards away. What brought him to my attention was what appeared to be a strobe light that was flashing. I have been thinking about and I was wondering if the new radar has some ways of taking pictures or if the strobe light really is the radar source. Any help would be appreciated. Thanks Jim Freeman
RE: radar
Does the photo show who was driving the car? Can't say that I would be too happy to be summoned to court when one of my kids (or wife) was speeding. Ghery Pettit -Original Message- From: Nick Rouse [mailto:nickjro...@cs.com] Sent: Tuesday, January 08, 2002 12:03 PM To: emc Subject: Re: radar I don't know if the technique is used in America but the speed cameras in the UK are triggered by radar but produce evidence by taking two pictures illuminated by two strobe pulses timed about 150ms apart. Stripes are painted across the road spaced so that between flashes a vehicle will traverse one stripe pitch for every 10mph.If the pictures show you have traversed more than 7 stripe pitches (on motorways)you will receive copies of these photos together with a summons to appear in court. Nick Rouse Jim Freeman wrote: Hi All, I apologize for being off subject but I was driving to work and noticed aCalifornia Highway Patrol officer on the opposite of the freeway an about 500 yards away. What brought him to my attention was what appeared to be a strobe light that was flashing. I have been thinking about and I was wondering if the new radar has some ways of taking pictures or if the strobe light really is the radar source. Any help would be appreciated. Thanks Jim Freeman Hi All, I apologize for being off subject but I was driving to work and noticed aCalifornia Highway Patrol officer on the opposite of the freeway an about 500 yards away. What brought him to my attention was what appeared to be a strobe light that was flashing. I have been thinking about and I was wondering if the new radar has some ways of taking pictures or if the strobe light really is the radar source. Any help would be appreciated. Thanks Jim Freeman
Re: radar
I don't know if the technique is used in America but the speed cameras in the UK are triggered by radar but produce evidence by taking two pictures illuminated by two strobe pulses timed about 150ms apart. Stripes are painted across the road spaced so that between flashes a vehicle will traverse one stripe pitch for every 10mph.If the pictures show you have traversed more than 7 stripe pitches (on motorways)you will receive copies of these photos together with a summons to appear in court. Nick Rouse Jim Freeman wrote: Hi All, I apologize for being off subject but I was driving to work and noticed aCalifornia Highway Patrol officer on the opposite of the freeway an about 500 yards away. What brought him to my attention was what appeared to be a strobe light that was flashing. I have been thinking about and I was wondering if the new radar has some ways of taking pictures or if the strobe light really is the radar source. Any help would be appreciated. Thanks Jim Freeman Hi All, I apologize for being off subject but I was driving to work and noticed aCalifornia Highway Patrol officer on the opposite of the freeway an about 500 yards away. What brought him to my attention was what appeared to be a strobe light that was flashing. I have been thinking about and I was wondering if the new radar has some ways of taking pictures or if the strobe light really is the radar source. Any help would be appreciated. Thanks Jim Freeman
RE: European and North American Cordage
Ron, On the first Network Attach product I helped develop, the IBM 4033 External Network Adapters, we wound up with 156 top bills-of-materials to cover three basic models (announced in 1991): * 4/16Mbps Token-Ring. * 10BASE-T/10BASE2 Ethernet. * 10BASE-T Ethernet). We had: * Two basic raw cards, with the Ethernet card being populated with/without the 10BASE2 components. times * Two sets of one-time-programmable (OTP) EPROM's, because the EPROM's were not big enough to hold both OS/2 and Netware code. times * Three power supplies-- a US/Canada single-output power supply, a worldwide dual-output power supply, and a Nordic dual-output power supply for Austria, Denmark, Finland, Norway, Sweden, and Switzerland because we could not get the worldwide power supply approved for these countries. times * Nine line cords. times * Five sets of documentation in English, French, German, Italian, and Spanish. This was a manufacturing nightmare, as you may imagine, just trying to keep all the different pieces in stock! Distribution was also a great pain, because we had to build units for specific markets and could not shuffle them to take care of excess demand in one country from excess inventory in another country. Customer service wasn't too happy with us either, because they had to keep six adapters and three power supplies in stock worldwide. Our next External Network Adapter, announced in 1993, was the Lexmark MarkNet XLe. We had two basic models, a 4/16Mbps Token-Ring unit and a 10BASE-T/10BASE2 unit, with two parallel ports. We had an optional serial port, making a total of four variants for the product. We included enough flash ROM on this unit to hold all the protocols that a customer would need (OS/2, Netware, unix's, etc.) (Scratch one set of EPROM's.) I again developed the power supply, this time a switcher operating from 90-256VAC 50-60Hz, and which we got approved for worldwide use. (Scratch two power supplies.) The power connector was an appliance input/output connector. We used a universal (HARSVT) jumper cord with an IEC 320-C13 shrouded male connector on one end and an IEC 320-C14 plug on the other end. We stole the linecord from a printer, and plugged it into the the appliance inlet. The jumper cord went from the appliance outlet on the MarkNet XLe to the printer's appliance input. (Scratch eight linecords.) The user documentation was in English, French, German, Italian, and Spanish, with technical documentation only in English. (Scratch four sets of documentation.) So, to sell four variants worldwide, we had only *four* top bills of material. We have used this same scheme on all of our External Network Adapters we have developed since 1993, and it has saved us a tremendous amount of grief in purchasing, manufacturing, distribution, and customer service. If you would like to see what kind of a mess you can get into for worldwide products, and how sweetly switcher power supplies and universal linecords can cover them, please take a look at Oscar Overton's and my webpage: ftp://ftp.lexmark.com/pub/networking/internat.htm THAT is why I like universal cordage. John Barnes Advisory Engineer Lexmark International --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
RE: European and North American Cordage
Because of the different mains plugs required in the different countries I have never seen much advantage to universal cordage. The one exception to this is a jumper cord that has an IEC320, C-13 connector on one end and a C-14 connector on the other. This type of power cord is independent of the mains connector and can be used in any country that is within the current limits. This minimizes the number of part numbers of jumper cords that need to be stocked and keeps the possiblity of putting the wrong cord into the box. MOO (My Opinions Only) WELLMAN,RON (A-PaloAlto,ex1) ron_wellman%agilent@interlock.lexmark.com on 01/08/2002 11:28:32 AM Please respond to WELLMAN,RON (A-PaloAlto,ex1) ron_wellman%agilent@interlock.lexmark.com To: 'jrbar...@lexmark.com' john_barnes.lexm...@sweeper.lex.lexmark.com, Peter Merguerian pmerguerian%itl.co...@interlock.lexmark.com, emc-pstc%majordomo.ieee@interlock.lexmark.com cc:(bcc: Oscar Overton/Lex/Lexmark) Subject: RE: European and North American Cordage Howdy all, Having been involved with power cords and cord sets for quite some time I have never seen an advantage in using Universal cordage. Therefore, I would be interested to hear from people what they have to say about their usage of Universal cordage and what they have benefited from using it. I am specifically interested in certification and material costs when using Universal cordage versus HAR or UL/CSA certified cordage. Regards, +=+ |Ronald R. Wellman|Voice : 408-345-8229 | |Agilent Technologies |FAX : 408-553-2412 | |5301 Stevens Creek Blvd.,|E-Mail: ron_well...@agilent.com| |Mailstop 54L-BB |WWW : http://www.agilent.com | |Santa Clara, California 95052 USA| | +=+ | Common sense is the collection of prejudices acquired by age | | eighteen. - Albert Einstein | +=+ -Original Message- From: jrbar...@lexmark.com [mailto:jrbar...@lexmark.com] Sent: Monday, January 07, 2002 2:21 PM To: Peter Merguerian; emc-p...@majordomo.ieee.org Subject: Re: European and North American Cordage Peter, We used a HARSVT 3x18AWG 1.00mm2 Universal linecord from Feller on the Lexmark MarNet XLe External Network Adapter. This had a Harmonized plus UL/CSA-listed cordage. I can't find my Feller catalog right now, and their website (http://www.feller-at.com/ ) doesn't say, but I think that they had HARSVT cordage in 16AWG and 14AWG, along with HARSJT cordage. John Barnes Advisory Engineer Lexmark International --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Heald
Fw: CEN Standards free on-line
Hi all, I think this resolves the questions. Eric -Original Message- From: Sanson Stewart [mailto:stewart.san...@cenorm.be] Sent: Tuesday, January 08, 2002 2:42 AM To: Eric Earnst Subject: RE: Electronic copies of standards Dera Sir Thanks! I have traced the error. For SOME CEN Workshops Agreements (in the ICT) field, where there is a compensatory payment of some kind, these will be put free on the web (actually some have already been there, I believe). As for all othzr European Standards - no, I am afraid not! Regards == Stewart Sanson - Public Relations Strategy and Business Development CEN - European Committee for Standardization Rue de Stassart 36, B-1050 Brussels Tel.: + 32 2 550 08 52 Fax: + 32 2 550 08 19 E-mail: mailto:stewart.san...@cenorm.be Web: http://www.cenorm.be == -Original Message- From: Eric Earnst [mailto:eear...@accuray.com] Sent: Tuesday, January 08, 2002 02:19 To: Sanson Stewart Subject: RE: Electronic copies of standards Hello, Somebody sent a link on a mailing list that I subscribe to for a press release on the europa.eu.int website: http://europa.eu.int/rapid/start/cgi/guesten.ksh?p_action.gettxt=gtdoc= IP/01/1837|0|RAPIDlg=EN The key text seems to be: The European Commission has welcomed the decision of the European Committee for Standardisation CEN to follow the European Telecommunications Standards Institute (ETSI) in publishing electronic standards on-line and free of charge from January 2002. I think this is what caused people to believe that the standards would become available though there has subsequently been much confusion over what the press release really means. Thanks, Eric --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
RE: European and North American Cordage
Howdy all, Having been involved with power cords and cord sets for quite some time I have never seen an advantage in using Universal cordage. Therefore, I would be interested to hear from people what they have to say about their usage of Universal cordage and what they have benefited from using it. I am specifically interested in certification and material costs when using Universal cordage versus HAR or UL/CSA certified cordage. Regards, +=+ |Ronald R. Wellman|Voice : 408-345-8229 | |Agilent Technologies |FAX : 408-553-2412 | |5301 Stevens Creek Blvd.,|E-Mail: ron_well...@agilent.com| |Mailstop 54L-BB |WWW : http://www.agilent.com | |Santa Clara, California 95052 USA| | +=+ | Common sense is the collection of prejudices acquired by age | | eighteen. - Albert Einstein | +=+ -Original Message- From: jrbar...@lexmark.com [mailto:jrbar...@lexmark.com] Sent: Monday, January 07, 2002 2:21 PM To: Peter Merguerian; emc-p...@majordomo.ieee.org Subject: Re: European and North American Cordage Peter, We used a HARSVT 3x18AWG 1.00mm2 Universal linecord from Feller on the Lexmark MarNet XLe External Network Adapter. This had a Harmonized plus UL/CSA-listed cordage. I can't find my Feller catalog right now, and their website (http://www.feller-at.com/ ) doesn't say, but I think that they had HARSVT cordage in 16AWG and 14AWG, along with HARSJT cordage. John Barnes Advisory Engineer Lexmark International --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
RE: SMPS Derating reqs for Altitude range of 5000-10000ft
Thank you for all your answers related to my question. I' ve got good ideas for this area and I appreciate your time and kindness to do it. Best wishes and Happy New Year to all of you! Regards, Carmen Filimon Leitch Canada -Original Message- From: Alexandru Guidea [SMTP:gui...@cae.com] Sent: Tuesday, January 08, 2002 8:57 AM To: 'Carmen.Filimon'; 'EMC Forum' Subject: RE: SMPS Derating reqs for Altitude range of 5000-1ft Importance: Low As mentioned by some colleagues in this forum, some thermal effects due to altitude are caused by reduced air density, which decreases the heath dissipation through convection. The percentage of heath dissipation by convection depends of the construction of each power supply (I don't believe most of the manufacturers are able to provide a number there). For terrestrial application, the convection being the dominant path, anything above 50% can be a good guess. By determining the density of the air at a given altitude versus normal operating level it can be determined the impact on convection, and ultimately the derating of the PS. To be noted that: forced air, or natural convection cooling processes are not affected the same way; PS' working in uncontrolled environments at high altitude can be affected by low ambient temperatures. And as a final note, sometimes the experiment is the fastest, easiest way. Alexandru Guidea CAE Inc. Canada (my opinion and only mine) -Original Message- From: Carmen.Filimon [mailto:carmen.fili...@leitch.com] Sent: Friday, January 04, 2002 11:28 AM To: EMC Forum Subject: SMPS Derating reqs for Altitude range of 5000-1ft Hi All I'm trying to find out what the specified operational altitude range(s) is (are) for power supplies (particularly switching mode ones). Do any of you know what that spec may be, and particularly what is the rule for derating at altitude for thermal issues. Many manufacturers don't specify a maximum altitude but instead design in enough thermal overhead to accommodate any reasonable terrestrial location. According to GR-63-CORE the operating range without derating is 1800m above sea level. If derating is required above 1800m then the manufacturer must specify any additional requirements. Is it a safety derating factor so that customers at 5000-1ft don't smell smoke? Do we have any recommendations for derating the operational temperature / power consumption of power supplies as the operational altitude increases? Any information or ideas you have would be appreciated. Regards, Carmen Filimon Leitch Canada --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
Don Bush's Death
I am posting this notice of Don Bush's death, as he was an EMC pioneer, and one of my employees from 1981-1993. Donald R. Bush recently passed away of cancer at the age of 59. Don received his MSEE at the University of Louisville and joined IBM in Lexington, Kentucky in 1965. At the time he became a pioneer in product design for electromagnetic compatibility, and worked as an EMC engineer his entire career. Don was a long and active member of IEEE, and presented numerous papers at EMC conferences. Don became a Lexmark employee when Lexmark was spun off from IBM in 1991. He retired about 1996 and formed his own consulting company, dBi. Although retired, Don was asked to participate in the Lexmark groundbreaking for a new state-of-the-art 10m semi- anechoic chamber. Sadly, this facility was completed and offically opened shortly after his death. He will be missed by his family, friends, co-workers, and the many EMC professionals he met over his 36 year career. George Alspaugh Lexmark International Inc. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
RE: Thermocouple alternatives
Another alternative I have used with good success for measuring temperature in a product (motor control, incubator etc..) is the AD590 solid-state device from Analog Devices. From their website: For supply voltages between +4 V and +30 V the device acts as a high impedance, constant current regulator passing 1 µA/K: http://products.analog.com/products/info.asp?product=AD590 I have used it to measure winding temperature in linear motors by potting it with the windings in certain applications with good success. Its main benefit is that it is easier (cheaper) to create conditioning circuitry than a thermocouple - just give it a voltage differential between 4 and 30V, and it gives you a current output that's pretty linear with temperature. The package size is small (either TO-52, or F-2A), but not as small as a thermocouple. From the viewpoint of product compliance testing, however, it is hard to beat the simplicity of taping/gluing thermocouples onto the components in question and using a commercial DAQ system. The cost per channel acquired is also quite low for compliance testing. I too have experienced noise and offset issues with using thermocouples in high-noise environments (PWM-driven servo motors). Solutions included electrically isolating the junction from the motor case (ground) and using ferrites with several turns. Thanks for the tip about trying T-type instead of K-type thermocouples, I'll give it a shot next time. I just noticed that Omega Engineering, Inc. sells thermocouple connectors with built-in ferrite cores for EMI suppression; though its probably just easier to grab some of the orphaned ferrites you probably have laying around anyway... Thanks for everyone's input. -Andy Andrew Veit Systems Design Engineer MTS Systems Corp 1001 Sheldon Drive Cary, NC 27513 --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
RE: Thermocouple alternative?
Good afternoon/morning everyone, As someone who designs Infrared Thermometers for a living I couldn't resist responding to some of the comments so far. Please don't take this as a plug for my companies products, the comments are meant to be general. -Original Message- From: Chris Maxwell [SMTP:chris.maxw...@nettest.com] Sent: 07 January 2002 16:20 To: Crabb, John; emc-p...@majordomo.ieee.org Subject: Re: Thermocouple alternative? Hi John, A possible solution would be to use an infrared non-contact thermometer. They measure temperature essentially by pointing them at the object of interest. They have a few drawbacks that I know of: 1. You need to have visual access to the part or surface of interest. Yes, this is fundamental to the operation. However there are fibreoptic thermometers available which greatly help with access. These are commonly used to measure inside induction heating furnaces for example. 2. You need to account for spot size since its detector essentially integrates all of the infrared in its field of view. The spot size changes with distance from the thermometer to the surface of interest. Variable focus helps here. Also there are thermometers available with nominally parallel field of view, over a specified useful working range. 3. If you are trying to graph temperature over time: you can't just glue it in place and hook it to a data logger. I don't know if it would be worth rigging up some kind of tripod to keep the infrared detector aimed at the point of interest. Many hand helds come with a tripod mount. Larger types should have all kind of mountings, cooling jackets , purges etc as required. We had one in the lab for a couple of days. It was a handheld, battery powered unit about the size of a Palm Pilot. Sadly, I only got to play with it a little bit before it was taken away. I wanted to see how accurate it was at measureing component temperatures on a circuitboard. Now days you can get relativley inexpensive hand held thermal imagers. These may be more suited to pcb work. - Ted Rook wrote: Yep, infrared point and shoot thermometers have some terrific advantages but another drawback with 'infra-red' instruments, they are calibrated for one value of surface emissivity. Before relying on the value for precision measurements you should familiarize yourself with Emissivity. Only low end products. Consider a thermometer with variable emissivity compensation. - Jeff jenkins wrote: I have had difficulty convincing agencies to accept data from non-contact thermal measurement systems, e.g., infrared or optical. The way that I have convinced them is to take side-by-side measurements on something that is not producing strong fields using a thermocouple and the non-contact measuring device. When they saw that the two devices measured the same temperature, they were satisfied. Thermometers are available with calibration traceable to UKAS or NIST standards. This should avoid such problems. If not supplied with traceable calibration by the manufacturer (many aren't) they can be calibrated independently afterwards by an independent lab just like other test gear. -- Benoit Nadeau wrote From an earlier life in a commercial EMC testing lab, I had one day this customer from Quebec City who developped a Fiber-optic based temperature sensing system. Their web site specifies that it is immune to RF. I think it is worth to look at: http://www.fiso.com/temp.htm These look interesting but note that they are not non-contact. Not an issue for applications such as transformer windings, but they are likely to have a higher thermal mass than thermocouples so care needed with small components. -- I also like John Woodgates suggestion of using precision thermistors. Very useful for measuring component temps on circuit boards etc. If anyone one wants any further help with any of the concepts then please contact me offline. Best regards Andy Wood Engineer- Special products Land Instruments International WWW.LANDINST.COM Infrared thermometry and calibration labs. This e-mail and its contents may be confidential, privileged and protected by law. Access is only authorised by the intended recipient. The contents of this e-mail may not be disclosed to, or used by, anyone other than the intended recipient, or stored or copied in any medium. If you are not the intended recipient, please advise the sender immediately. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site
RE: LISN for automotive directive
I would like to see if the one per CISPR 25 suits for this purpose or not. I am not sure that 95/54/EC requires you to perform conducted emissions, but if you do, the standard will be CISPR-25, so the short answer is YES. Best regards - Chris -Original Message- From: KC CHAN [PDD] [SMTP:kcc...@hkpc.org] Sent: Tuesday, January 08, 2002 12:48 AM To: emc-p...@majordomo.ieee.org Subject:LISN for automotive directive Hi all I am looking for a LISN for the automobile conducted emission testing under the automotive directive 95/54, one of the suppliers has suggested the one per CISPR 25. Since there is no clear construction in the automotive directive, I would like to see if the one per CISPR 25 suits for this purpose or not. Thank you KC Chan --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server. This e-mail has been scanned for all viruses by Star Internet. The service is powered by MessageLabs. For more information on a proactive antivirus service working around the clock, around the globe, visit: www.star.net.uk This e-mail has been scanned for all viruses by Star Internet. The service is powered by MessageLabs. For more information on a proactive antivirus service working around the clock, around the globe, visit: www.star.net.uk --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
Re: EMC-related safety issues
I read in !emc-pstc that Wan Juang Foo f...@np.edu.sg wrote (in of20fd77f8.c4438312-on48256b3b.002ee...@np.edu.sg) about 'EMC-related safety issues', on Tue, 8 Jan 2002: EMI from the ASMD (anti ship missile defence) radar had cause the communication equipment to be inoperable. During this brief period, an Exocet missile was not seen homing in on HMS Sheffield According to a TV documentary the other day, the two systems were on nearly the same frequency, so this was really a case of a clash between military and civilian spectrum usage rather than normal EMC. Note 'usage'; at that time the military had almost carte blanche on spectrum usage, especially in a combat situation. Presumably the Commander (E) should have ditched the satellite link, but the TV documentary said that the surveillance radar lost the echoes from the Super-Etandards flying at zero altitude and the potential threat was not passed on to Commander (E). The moral here is that you ALWAYS give Jack-the-Operator the benefit of the doubt if he says he saw or heard something, whether it's radar or ASDIC. These days, it is at least alleged that there is much better co- ordination between the UK military and the civil authority on spectrum usage. -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk After swimming across the Hellespont, I felt like a Hero. --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
RE: Comparing EMI test results
Hi All, Thanks everyone who replied and offerred their suggestions regarding this topic. Praveen I'm trying to setup a programme to compare test results (for Radiated Emissions) between test labs. The plan is to circulate a Artifact around the labs and compare the results. The test sites being compared are Semi-anechoic Chambers v/s OATS. The source used is a wideband RF comb generator. I would like to understand the concept fully before I initiate this programme. Is there any information readily available on this topic? Any help will be greatly appreciated. Thanks. Praveen Thanks for the response. The purpose is to test both, the facility (semi-anechoic v/s OATS) and the quality of results. The comb generator is my first approach. A standard test sample(with cables) will follow. Any procedures, data, results, experience on this issue ? --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
Re: radar
I think what you saw was a strobe light that was flashing. It has nothing to do with the mechanics, only the image. It appears that the CHP feels that when you see someone getting a ticket you speed up since you regard that officer as otherwise engaged. When you see a CHP with his radar gun cocked, everyone slows down. He doesn't even have to turn it on to be effective. In fact if he leaves it off, it enforcesthe image of steal technology that can't be detected by radar detectors. Fred Townsend Jim Freeman wrote: Hi All, I apologize for being off subject but I was driving to work and noticed aCalifornia Highway Patrol officer on the opposite of the freeway an about 500 yards away. What brought him to my attention was what appeared to be a strobe light that was flashing. I have been thinking about and I was wondering if the new radar has some ways of taking pictures or if the strobe light really is the radar source. Any help would be appreciated. Thanks Jim Freeman --- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson:pstc_ad...@garretson.org Dave Healddavehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
