RE: Off Subject - Load Rating of Wood Blocks
Hi, As an ex-nuclear submariner, one of the neatest things I've seen is a submarine in a dry dock with only a row of blocks down the centerline holding it up. The blocks were made of oak... http://www.arco.navy.mil/build.htm http://www.arco.navy.mil/26%20Arco%20Crew%20in%20drydock%20with%20Sub.JP G Eric From: emc-p...@ieee.org [mailto:emc-p...@ieee.org] On Behalf Of Scott Lacey Sent: Sunday, March 19, 2006 6:42 AM To: emc-p...@ieee.org Subject: Off Subject - Load Rating of Wood Blocks To the group: I hope someone can provide insight on this. In a situation where the machinery maintenance people routinely use wood blocks to support parts of machinery while it is being worked on management has ordered all wood to be thrown away and replaced with load-rated substitutes made of welded steel. The maintenance people are concerned that steel will be more unstable than wood due to the lubricating effect of spilled hydraulic fluid. They are also concerned that due to cost there will be only a small supply of the new blocks available. As of now the wood blocks are left in place while waiting for new parts. Sometimes it takes weeks for the parts to come in. Does anyone know of a source for "calibrated" wood blocks or a process to certify blocks made from a known species such as oak? Thanks Scott B. Lacey - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list.Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to emc-p...@ieee.org Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas emcp...@ptcnh.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher: j.bac...@ieee.org David Heald:emc-p...@daveheald.com All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc WARNING CONFIDENTIAL INFORMATION: The information contained in the e-mail may contain confidential and privileged information and is intended solely for the use of the intended recipient(s). Access for any review, re-transmission, dissemination or other use of, or taking of any action in regard and reliance upon this e-mail by persons or entities other than the intended recipient(s) is unauthorized and prohibited. If you are not the intended recipient, please contact the sender by reply e-mail and destroy all copies of the original message and any attachments. - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list.Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to emc-p...@ieee.org Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas emcp...@ptcnh.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher: j.bac...@ieee.org David Heald:emc-p...@daveheald.com All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
RE: Hipot testing following fault testing
The scenario we were really thinking of is in your paragraph starting with "However..." Suppose for example we are fault testing a power supply that supplies SELV circuits from the mains. There are any number of faults you could apply in the p/s control or load circuits that might stress the transformer. After the test you need to verify that this Reinforced isolation transformer still has adequate insulation remaining after the fault. Since it is after a fault, I would argue that the test from primary to secondary should be done at the level required for Basic insulation. Why should it still be Reinforced after a fault has been applied? Jim Eichner, P.Eng. Compliance Engineering Manager Xantrex Technology Inc. phone: (604) 422-2546 fax: (604) 420-1591 e-mail: jim.eich...@xantrex.com web: www.xantrex.com Confidentiality Notice: This email message, including any attachments, is for the sole use of the intended recipient(s) and may contain confidential and privileged information. Any unauthorized review, use, disclosure or distribution is prohibited. If you are not the intended recipient, please contact the sender by reply e-mail and destroy all copies of the original message. From: emc-p...@ieee.org [mailto:emc-p...@ieee.org] On Behalf Of Peter Tarver Sent: Monday, March 20, 2006 1:56 PM To: emc-p...@ieee.org Subject: RE: Hipot testing following fault testing Hi, Jim. Based on your question, it appears you're discussing faults of insulation. On that basis, no faulting of Reinforced Insulation is called for. However, if faults: on the component containing the Reinforced Insulation (say, overload testing of a transformer, per Annex C1) [the concept applied by extension, even though Annex C was not mentioned in you r question] of components other than the component containing the Reinforced Insulation of other insulation can cause excessive temperatures or excessive voltages to appear across Reinforced Insulation, there is reason to perform a hipot test after the fault test on the Reinforced Insulation at the levels called out for Subclause 5.2. Further, in the case of faulting Basic Insulation as a part of Double Insulation (assuming such testing is accommodated by product construction), the post fault test hipot would be based on the value for and applied across the Supplementary Insulation that was theoretically stressed by the fault of Basic Insulation. The idea being that the second level of protection is not degraded (similar that pointed out by your example of earthing remaining intact where it provides the second level of protection). If you're fault testing components that bridge Reinforced Insulation, other considerations may come into play, but post fault hipot testing would likely follow a similar logic to the above. Regards, Peter L. Tarver, PE ptar...@ieee.org _ Scanned by Sanmina-SCI eShield _ - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list.Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to emc-p...@ieee.org Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas emcp...@ptcnh.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher: j.bac...@ieee.org David Heald:emc-p...@daveheald.com All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list.Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to emc-p...@ieee.org Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas emcp...@ptcnh.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher: j.bac...@ieee.org David Heald:emc-p...@daveheald.com All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
Re: RF field strength units
Bill Flanigan asked: >> I have purchased a field-strength meter which displays - over a range of frequencies - field strength in units dBmV, dBuV or dBm. It uses a whip antenna. Is there any way to convert any of these figures to V/m (I am doing RF immunity testing and I need to ensure 10 V/m)? Or is this << It may not be useful for _this_ purpose. >From the description, it is an RF voltmeter with a whip. If accurately calibrated, it could be quite helpful comparing "before and after" fields. However, in order to tell what the field IS, you need the whip's antenna factor (installed on the instrument) and it is more than possible the manufacturer doesn't know that. If you can connect an antenna whose factors are known, you need only sum that with the reading you get. 0 dBmV is 1 millivolt. 1 volt is 1000 mV, 60 dBmV; 10 volts is 10,000 mV, 80 dBmV. A biconical dipole might from 30 to 200 MHz have an antenna factor varying between 6dB and 30dB (or higher). In a field of 10 V/m, that antenna would deliver (not counting feedline loss) anywhere between 316 mV and 5 volts. The corresponding numbers in dBmV are 50 dBmV to 74 dBmV. And if your instrument has a flat response across the frequencies you want to measure, it'll work. That was the last of the good news; using a bicon or other full-sized antenna affects the field one is measuring. For checking radiated fields for immunity testing, you need really small antennas (and instruments). Since a 10V/m field demands no great sensitivity, commercial sensors for immunity work usually have 3-axis (polarization irrelevant) short, resistive dipoles with detectors at the antenna feeding rectified DC to a high impedance measuring circuit, and also, with some way to get the readings out of the chamber without affecting the field with long wires; fiber optic, usually. You pay for this; precision and suitability for the job don't come cheap. Good luck! Cortland KA5S - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list.Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to emc-p...@ieee.org Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas emcp...@ptcnh.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher: j.bac...@ieee.org David Heald:emc-p...@daveheald.com All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
RE: RF field strength units
Bill: The "antenna factor" is a conversion factor that converts the field strength of an E-Field that the antenna sees to the voltage (Volts or micro-volts present on the output terminals of the antenna into a specified load (Normally 50 ohms). The AF for an antenna will vary over frequency. Therefore, the manufacturer should generally provide you with a graph showing frequency vs. AF, or a suitable table. The other option is to have the antenna calibrated by a lab that performs that service such as Liberty Labs. If you are going that route, be sure to specify how you are going to use the antenna. (Immunity vs. radiated emissions measurements). John Shinn, P.E. Manager, Laboratory Operations Sanmina-SCI _ From: emc-p...@ieee.org [mailto:emc-p...@ieee.org] On Behalf Of Bill Flanigan Sent: Monday, March 20, 2006 11:17 AM To: 'Emc-Pstc' Subject: RF field strength units Associates, I have purchased a field-strength meter which displays - over a range of frequencies - field strength in units dBmV, dBuV or dBm. It uses a whip antenna. Is there any way to convert any of these figures to V/m (I am doing RF immunity testing and I need to ensure 10 V/m)? Or is this conversion dependent on knowing the antenna factors over the frequency ranges? I am in the middle of unproductive communications with the manufacturer (Korea) and the vendor (Arizona). WmFlanigan _ Scanned by Sanmina-SCI eShield - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to emc-p...@ieee.org Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas emcp...@ptcnh.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher: j.bac...@ieee.org David Heald: emc-p...@daveheald.com All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc _ Scanned by Sanmina-SCI eShield - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to emc-p...@ieee.org Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas emcp...@ptcnh.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher: j.bac...@ieee.org David Heald: emc-p...@daveheald.com All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
RE: Hipot testing following fault testing
Hi, Jim. Based on your question, it appears you're discussing faults of insulation. On that basis, no faulting of Reinforced Insulation is called for. However, if faults: on the component containing the Reinforced Insulation (say, overload testing of a transformer, per Annex C1) [the concept applied by extension, even though Annex C was not mentioned in you r question] of components other than the component containing the Reinforced Insulation of other insulation can cause excessive temperatures or excessive voltages to appear across Reinforced Insulation, there is reason to perform a hipot test after the fault test on the Reinforced Insulation at the levels called out for Subclause 5.2. Further, in the case of faulting Basic Insulation as a part of Double Insulation (assuming such testing is accommodated by product construction), the post fault test hipot would be based on the value for and applied across the Supplementary Insulation that was theoretically stressed by the fault of Basic Insulation. The idea being that the second level of protection is not degraded (similar that pointed out by your example of earthing remaining intact where it provides the second level of protection). If you're fault testing components that bridge Reinforced Insulation, other considerations may come into play, but post fault hipot testing would likely follow a similar logic to the above. Regards, Peter L. Tarver, PE ptar...@ieee.org _ Scanned by Sanmina-SCI eShield ___ _ - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list.Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to emc-p...@ieee.org Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas emcp...@ptcnh.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher: j.bac...@ieee.org David Heald:emc-p...@daveheald.com All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
RE: [Fwd: Re: Calibration of test equipment]
> From: Jon Griver > Sent: Monday, March 20, 2006 2:03 AM > > It is my understanding that it is purely the responsibility > of the owner > of the measuring instrument to decide on the calibration period. Hi, Jon. ISO 17025, Subclause 5.10.4.4, agrees with you. However, in dealing with various agencies and auditors, the consensus seems to be that the calibration period should not be longer than that recommended by the equipment manufacturer, but the periods may be shorter. Regards, Peter L. Tarver, PE ptar...@ieee.org _ Scanned by Sanmina-SCI eShield ___ _ - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list.Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to emc-p...@ieee.org Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas emcp...@ptcnh.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher: j.bac...@ieee.org David Heald:emc-p...@daveheald.com All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
RF field strength units
Associates, I have purchased a field-strength meter which displays - over a range of frequencies - field strength in units dBmV, dBuV or dBm. It uses a whip antenna. Is there any way to convert any of these figures to V/m (I am doing RF immunity testing and I need to ensure 10 V/m)? Or is this conversion dependent on knowing the antenna factors over the frequency ranges? I am in the middle of unproductive communications with the manufacturer (Korea) and the vendor (Arizona). WmFlanigan - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to emc-p...@ieee.org Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas emcp...@ptcnh.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher: j.bac...@ieee.org David Heald: emc-p...@daveheald.com All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
RE: Calibration of test equipment
Ron - At a previous employer, we operated under CSA Category Certification Program. One of the basic requirements at the time was compliance with ISO Guide 25 (later becoming 17025). The point is that any company using the CCP that was not already compliant with ISO 17025 should have been ineligible or dropped from the program. Or do you mean CSA is moving toward exclusively using external registration organizations, rather than CSA engineers auditing for themselves? Regards, Peter L. Tarver, PE ptar...@ieee.org > From: Ronald R. Wellman > Sent: Friday, March 17, 2006 7:14 AM > > There have been many responses to this question regarding > MRAs. However, I don't know if anyone is aware that the > Canadian Standards Association (CSA) is in the process to > eventually have their category certification clients at least > ISO 17025 compliant. Also, as far as calibration interval, if > you are a calibration lab, you have the option to provide > your Customers different calibration plans. Therefore, you > can decide on anything that meets your Customer needs. > > > Best regards, > Ron Wellman > _ Scanned by Sanmina-SCI eShield ___ _ - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list.Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to emc-p...@ieee.org Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas emcp...@ptcnh.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher: j.bac...@ieee.org David Heald:emc-p...@daveheald.com All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
RE: Calibration of test equipment
Hi Mike The calibration interval really depends on the standards in your scope of accreditation as much or more than any agreement between the manufacturer and test lab. For example, if you are testing to ANSI C63.4 (i.e. any FCC part 15 device) the section 4.4.1 has a maximum interval allowance of up to 2 years or shorter. Other standards may require other intervals. If there is no specified interval in the standard being used then the manufacturer and lab can agree on a reasonable interval. Dennis Ward Evaluation Engineer American TCB Certification Resource for the Wireless Industry www.atcb.com 703-847-4700 fax 703-847-6888 direct - 703-880-4841 cell - 209-769-8316 NOTICE: This E-Mail message and any attachment may contain privileged or company proprietary information. If you received this message in error, please return to the sender. From: emc-p...@ieee.org [mailto:emc-p...@ieee.org] On Behalf Of rehel...@mmm.com Sent: 03/20/2006 1:07 AM To: emc-p...@ieee.org Subject: Re: Calibration of test equipment Mike, I have searched for this answer before. I have not found anything anywhere that requires a specific time period between calibration. Just manufacturers recommendations or whatever is agreed between you and your calibration lab. The dangers of extending it beyond a year has been documented previously. Bob Heller 3M EMC Laboratory, 76-1-01 St. Paul, MN 55107-1208 Tel: 651- 778-6336 Fax: 651-778-6252 = "Mike Hopkins" To Sent by: emc-p...@ieee.org cc "Tricia Rakiey" 03/16/2006 03:31 Subject PMCalibration of test equipment It's my understanding that the MRA's require that test instruments used for compliance to European Norms be calibrated by an accredited lab --- in the US, NVLAP, A2LA, and (another?). As a manfacturer, we recommend our products be calibrated yearly. ISO 17025 includes clause 5.10.4.4, which states: "The calibration certificate (or calibration lable) shall not contain any recommendation on the calibration interval except where this has been agreed with the customer. This requirement may be superseded by legal regulations." ISO 17025 is, of course, the basis of accreditation to NVLAP or A2LA and others... My question to the group is: Is there some requirement under the MRA's or European Norms that states equipment must be calibrated periodically, and is "periodically" defined?? It seems to me allowing the customer to decide on when calibration is due (per ISO) can lead to no requirement for calibrations at all, which in turn, puts the whole accreditation issue in question... I find this hard to believe, but I haven't identified a paragraph makes it clear.. Best Regards, Michael Hopkins Manager, Customer Technical Center Process Instruments Division Thermo Electron Corporation One Lowell Research Center Lowell, MA 01852 Tel: +1 978 275 0800 ext. 334 Mobile: +1 603 765 3736 michael.hopk...@thermo.com www.thermo.com/esd - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to emc-p...@ieee.org Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas emcp...@ptcnh.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher: j.bac...@ieee.org David Heald: emc-p...@daveheald.com All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list.Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to emc-p...@ieee.org Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrator
Value of a Declaration of Incorporation (DoI)
Return Receipt Your Value of a Declaration of Incorporation (DoI) document: was received John Radomski/Aut/Schneider by: at: 03/20/2006 07:08:33 - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list.Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to emc-p...@ieee.org Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas emcp...@ptcnh.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher: j.bac...@ieee.org David Heald:emc-p...@daveheald.com All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
RE: Off Subject - Load Rating of Wood Blocks
Scott, I have a book titled something like Modern Timber Design (1948) that lists the strength of all types of wood. I will take a look at it tonight and see if there is any good information for you. Dave Cuthbert Micron Technology, Inc. From: emc-p...@ieee.org [mailto:emc-p...@ieee.org] On Behalf Of Scott Lacey Sent: Sunday, March 19, 2006 7:42 AM To: emc-p...@ieee.org Subject: Off Subject - Load Rating of Wood Blocks To the group: I hope someone can provide insight on this. In a situation where the machinery maintenance people routinely use wood blocks to support parts of machinery while it is being worked on management has ordered all wood to be thrown away and replaced with load-rated substitutes made of welded steel. The maintenance people are concerned that steel will be more unstable than wood due to the lubricating effect of spilled hydraulic fluid. They are also concerned that due to cost there will be only a small supply of the new blocks available. As of now the wood blocks are left in place while waiting for new parts. Sometimes it takes weeks for the parts to come in. Does anyone know of a source for "calibrated" wood blocks or a process to certify blocks made from a known species such as oak? Thanks Scott B. Lacey - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list.Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to emc-p...@ieee.org Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas emcp...@ptcnh.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher: j.bac...@ieee.org David Heald:emc-p...@daveheald.com All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list.Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to emc-p...@ieee.org Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas emcp...@ptcnh.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher: j.bac...@ieee.org David Heald:emc-p...@daveheald.com All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
RE: Calibration of test equipment
All, While I do not know of any specific requirement, I know that some companies operate on the basis of having the equipment checked to confirm that it is "in cal" before any adjustments are made. If the equipment happens to be out-of-cal, then we know which functions and by how much it is in error. This information is required to assess whether there is a need to go back through the measurements it was used for, to decide if repeats, recalls etc are required. Adjustment / repair is carried out and then the equipment is calibrated. If the equipment is in-cal on the first pass, then, depending on the equipment and the need for routine adjustments the device is re-cal'ed or not. If a particular piece of equipment has a history of being out-of-cal at the time it is sent for calibration, then the calibration period is reduced. Similarly, if a particular piece of equipment is always spot-on calibration, then the calibration period is increased. Generally, the aim is to keep the equipment in cal but needing a slight adjustment to "centre" it. Makers recommendations are significant and are usually followed until we have a history to go by in order to extend or reduce the period. The calibration process described is more expensive than the usual type of process. However, if the equipment was significantly out of cal, then the task it had been used of may have erroneous results. If this could lead to significant costs / damages etc., it could be well worth the extra on the calibration bill. I hope I have described this adequately well. Regards Tim From: emc-p...@ieee.org [mailto:emc-p...@ieee.org]On Behalf Of rehel...@mmm.com Sent: 20 March 2006 09:07 To: emc-p...@ieee.org Subject: Re: Calibration of test equipment *** WARNING *** This mail has originated outside your organization, either from an external partner or the Global Internet. Keep this in mind if you answer this message. Mike, I have searched for this answer before. I have not found anything anywhere that requires a specific time period between calibration. Just manufacturers recommendations or whatever is agreed between you and your calibration lab. The dangers of extending it beyond a year has been documented previously. Bob Heller 3M EMC Laboratory, 76-1-01 St. Paul, MN 55107-1208 Tel: 651- 778-6336 Fax: 651-778-6252 = "Mike Hopkins" To Sent by: emc-p...@ieee.org cc "Tricia Rakiey" 03/16/2006 03:31 Subject PMCalibration of test equipment It's my understanding that the MRA's require that test instruments used for compliance to European Norms be calibrated by an accredited lab --- in the US, NVLAP, A2LA, and (another?). As a manfacturer, we recommend our products be calibrated yearly. ISO 17025 includes clause 5.10.4.4, which states: "The calibration certificate (or calibration lable) shall not contain any recommendation on the calibration interval except where this has been agreed with the customer. This requirement may be superseded by legal regulations." ISO 17025 is, of course, the basis of accreditation to NVLAP or A2LA and others... My question to the group is: Is there some requirement under the MRA's or European Norms that states equipment must be calibrated periodically, and is "periodically" defined?? It seems to me allowing the customer to decide on when calibration is due (per ISO) can lead to no requirement for calibrations at all, which in turn, puts the whole accreditation issue in question….. I find this hard to believe, but I haven't identified a paragraph makes it clear…. Best Regards, Michael Hopkins Manager, Customer Technical Center Process Instruments Division Thermo Electron Corporation One Lowell Research Center Lowell, MA 01852 Tel: +1 978 275 0800 ext. 334 Mobile: +1 603 765 3736 michael.hopk...@thermo.com www.thermo.com/esd - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list.
Re: Off Subject - Load Rating of Wood Blocks
In message , dated Mon, 20 Mar 2006, ted.eck...@apcc.com writes >As a side note, would automobile jack stands work for your application? >They are designed to support heavy weights for long periods, they are >load rated, they are designed for oily conditions and they have a >cradle on top to provide a good support. Generally, in my experience, the problem is that they need a large flat support surface, which is never present. -- OOO - Own Opinions Only. Try www.jmwa.demon.co.uk and www.isce.org.uk 2006 is YMMVI- Your mileage may vary immensely. John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list.Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to emc-p...@ieee.org Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas emcp...@ptcnh.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher: j.bac...@ieee.org David Heald:emc-p...@daveheald.com All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
[Fwd: Re: Calibration of test equipment]
Mike, It is my understanding that it is purely the responsibility of the owner of the measuring instrument to decide on the calibration period. The calibration laboratory has a financial interest in 'encouraging' its customers to calibrate frequently, but only the customer knows the use to which the instrument is put, and the calibration history. For instance, it may be quite reasonable for gauge blocks, used infrequently to internally calibrate vernier calipers, to be sent out to an external lab for calibration once every five years. On the other hand, the appropriate calibration interval for a vernier caliper in constant use on the production line may be one month or less, especially if the result of out-of-calibration measurements could be a product recall. Ultimately the manufacturer must take responsibility. If you think about it, I don't think that a calibration laboratory's insurers would want them to take responsibility for specifying calibration periods which may be inappropriate for the actual use to which the measuring device is put. Jon Griver http://www.601help.com The Medical Device Designers' Guide to IEC 60601-1 Subject: Re: Calibration of test equipment From:rehel...@mmm.com List-Post: emc-pstc@listserv.ieee.org Date:Mon, March 20, 2006 4:06 am To: emc-p...@ieee.org Mike, I have searched for this answer before. I have not found anything anywhere that requires a specific time period between calibration. Just manufacturers recommendations or whatever is agreed between you and your calibration lab. The dangers of extending it beyond a year has been documented previously. Bob Heller 3M EMC Laboratory, 76-1-01 St. Paul, MN 55107-1208 Tel: 651- 778-6336 Fax: 651-778-6252 = It's my understanding that the MRA's require that test instruments used for compliance to European Norms be calibrated by an accredited lab --- in the US, NVLAP, A2LA, and (another?). As a manfacturer, we recommend our products be calibrated yearly. ISO 17025 includes clause 5.10.4.4, which states: "The calibration certificate (or calibration lable) shall not contain any recommendation on the calibration interval except where this has been agreed with the customer. This requirement may be superseded by legal regulations." ISO 17025 is, of course, the basis of accreditation to NVLAP or A2LA and others... My question to the group is: Is there some requirement under the MRA's or European Norms that states equipment must be calibrated periodically, and is "periodically" defined?? It seems to me allowing the customer to decide on when calibration is due (per ISO) can lead to no requirement for calibrations at all, which in turn, puts the whole accreditation issue in question….. I find this hard to believe, but I haven't identified a paragraph makes it clear…. Best Regards, Michael Hopkins Manager, Customer Technical Center Process Instruments Division Thermo Electron Corporation One Lowell Research Center Lowell, MA 01852 Tel: +1 978 275 0800 ext. 334 Mobile: +1 603 765 3736 michael.hopk...@thermo.com www.thermo.com/esd - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list.Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to emc-p...@ieee.org Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas emcp...@ptcnh.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher: j.bac...@ieee.org David Heald:emc-p...@daveheald.com All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
Re: Off Subject - Load Rating of Wood Blocks
Call your insurance provider and ask them to send out a risk analyst. This person will look at the situation and determine if it is acceptable to use wood or if metal supports are required. Both you and your insurance company should have three goals. First, you want to make sure that nobody is injured. Second, you want to minimize the legal costs if somebody is injured. Third, you want to find the most economical solution to the problem. A good risk analyst can look at your situation and tell you the best solution. The wood may be acceptable for your application. If not, the analyst has probably seen similar situations and probably knows the most economical solution that meets safety requirements. There is a good chance that your insurance company will send out the analyst for free. They want to avoid injuries as much as you do because they have to pay for any injury. Just remember that a single injury could cost ten times as much as a good set of custom supports. As a side note, would automobile jack stands work for your application? They are designed to support heavy weights for long periods, they are load rated, they are designed for oily conditions and they have a cradle on top to provide a good support. As I have little information on the specifics of your application, I can only make general suggestions. Ted Eckert American Power Conversion Corporation The items contained in this e-mail reflect the personal opinions of the writer and are only provided for the assistance of the reader. The writer is not speaking in an official capacity for APC nor representing APC's official position on any matter. - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list.Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to emc-p...@ieee.org Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas emcp...@ptcnh.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher: j.bac...@ieee.org David Heald:emc-p...@daveheald.com All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
Re: Calibration of test equipment
Mike, I have searched for this answer before. I have not found anything anywhere that requires a specific time period between calibration. Just manufacturers recommendations or whatever is agreed between you and your calibration lab. The dangers of extending it beyond a year has been documented previously. Bob Heller 3M EMC Laboratory, 76-1-01 St. Paul, MN 55107-1208 Tel: 651- 778-6336 Fax: 651-778-6252 = "Mike Hopkins" To Sent by: emc-p...@ieee.org cc "Tricia Rakiey" 03/16/2006 03:31 Subject PMCalibration of test equipment It's my understanding that the MRA's require that test instruments used for compliance to European Norms be calibrated by an accredited lab --- in the US, NVLAP, A2LA, and (another?). As a manfacturer, we recommend our products be calibrated yearly. ISO 17025 includes clause 5.10.4.4, which states: "The calibration certificate (or calibration lable) shall not contain any recommendation on the calibration interval except where this has been agreed with the customer. This requirement may be superseded by legal regulations." ISO 17025 is, of course, the basis of accreditation to NVLAP or A2LA and others... My question to the group is: Is there some requirement under the MRA's or European Norms that states equipment must be calibrated periodically, and is "periodically" defined?? It seems to me allowing the customer to decide on when calibration is due (per ISO) can lead to no requirement for calibrations at all, which in turn, puts the whole accreditation issue in question….. I find this hard to believe, but I haven't identified a paragraph makes it clear…. Best Regards, Michael Hopkins Manager, Customer Technical Center Process Instruments Division Thermo Electron Corporation One Lowell Research Center Lowell, MA 01852 Tel: +1 978 275 0800 ext. 334 Mobile: +1 603 765 3736 michael.hopk...@thermo.com www.thermo.com/esd - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to emc-p...@ieee.org Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas emcp...@ptcnh.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher: j.bac...@ieee.org David Heald: emc-p...@daveheald.com All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list.Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to emc-p...@ieee.org Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas emcp...@ptcnh.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher: j.bac...@ieee.org David Heald:emc-p...@daveheald.com All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc