RE: Production Line Test Requirements - Medical Devices
Dear Jon, Dick and All Memebers, I believe the UL method for Production-Line Grounding Continuity Test is just to verify that someone did not forget to connect the earthing lead from the appliance inlet or power corrd to the chassis. Therefore an ohmmeter, buzzer or the like is all that is considered necessary. The feeding of an ac or dc current between the protective earth terminal and other parts of the unit likely to be energized by a single insulation fault is not necessary during the production-line tests because these tests have already been conducted by the lab during the type tests. UL and other NRTLs want to make sure that assembler did not forget to connect the main earthing lead. Also, if you check a UL or NRTL descriptive report used for the quarterly folow-up inspections, you will note that the construction of the product has been described in detail, including but not limited to earthing connections, enclosure, covers, screws and washers, etc. European test labs for follow-up purposes, use a Critical Components List but do not describe the construction of the product in detail. Hence, they require the feeding on an ac or dc low voltage current source into the earthing path for each production unit. Regards PETER S. MERGUERIAN Technical Director I.T.L. (Product Testing) Ltd. 26 Hacharoshet St., POB 211 Or Yehuda 60251, Israel Tel: + 972-(0)3-5339022 Fax: + 972-(0)3-5339019 Mobile: + 972-(0)54-838175 -Original Message- From: Jon Griver [mailto:jo...@medson.com] Sent: Tuesday, May 22, 2001 9:06 AM To: Dick Grobner Cc: emc-p...@majordomo.ieee.org Subject: RE: Production Line Test Requirements - Medical Devices Dick, This is the situation as I understand it. Please note that a few years ago I did factory inspections for TUV Rheinland, so I'm speaking from a position of some knowledge (though a bit outdated). UL includes its production test requirements in its standards. It traditionally has only required a check of earth continuity under low current conditions. The European test labs work on the basis of extracting production tests from the standards. They require these tests to be performed as a condition of using their mark on the product. It is the test lab's decision which production tests are to be performed and it is not mandated by any standard. Traditionally, the European test labs require the earth continuity test to be carried out at high current conditions, as in the standard. The logic behind this is that if there is a fault to earth, it will cause a high current which may cause any weak links in the earth circuit to heat up and possibly char and increase in resistance or even burn out completely. (We've all seen charring around sockets). Thus this test is considered more effective in identifying loose connections, etc. due to production mistakes than the UL test, which might miss them. Presumably if you are selling your medical product in the EU, you have a Notified Body (unless your product is Group 1). You should agree your production test plan with them. Be aware that they may insist on the high current earth continuity test. Good Luck, Jon Griver Medson Ltd -Original Message- From: Dick Grobner [mailto:dick.grob...@medgraph.com] Sent: Monday, May 21, 2001 18:23 To: 'Jon Griver' Cc: IEEE EMC-PSTC E-Mail Forum (E-mail) Subject: RE: Production Line Test Requirements - Medical Devices Jon Thx for the info, however, I re-checked the two known US standards (UL2601, Appendix D - Manufacturer's Responsibilities, Construction Considerations and Requirements for Factory Tests) (NFPA 99, Grounding Circuit Continuity - Measurement of Resistance). UL defines Production Line Grounding Continuity Test Equipment as: Any suitable continuity indication device (such as an ohmmeter, a battery and buzzer combination, or the like) may be used to determine compliance with Grounding Continuity Test requirements. The NFPA std is even less definitive on this matter. EN60601-1, Appendix B - Testing During Manufacture and/or Installation, Not Used. See rational to sub-clause 4.1. Which states - Tests described in this standard are type tests. I checked all of the amendments including EN60601-1 for medical systems, and I do not see anything changing this. My questions remains, where does it state to use the 10-25Amp, 50 or 60Hz @ 6Volt for 5 seconds test? Is this a carry over from another EN standard? Why wouldn't a simple continuity tests as defined by UL be appropriate from equipment coming off of the production line (assuring that the protective earth circuit in intake)? Appreciate your feedback Jon! thanks again. Does anyone else on this forum have any input - would appreciate it. --- 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
RE: Production Line Test Requirements - Medical Devices
Dick, This is the situation as I understand it. Please note that a few years ago I did factory inspections for TUV Rheinland, so I'm speaking from a position of some knowledge (though a bit outdated). UL includes its production test requirements in its standards. It traditionally has only required a check of earth continuity under low current conditions. The European test labs work on the basis of extracting production tests from the standards. They require these tests to be performed as a condition of using their mark on the product. It is the test lab's decision which production tests are to be performed and it is not mandated by any standard. Traditionally, the European test labs require the earth continuity test to be carried out at high current conditions, as in the standard. The logic behind this is that if there is a fault to earth, it will cause a high current which may cause any weak links in the earth circuit to heat up and possibly char and increase in resistance or even burn out completely. (We've all seen charring around sockets). Thus this test is considered more effective in identifying loose connections, etc. due to production mistakes than the UL test, which might miss them. Presumably if you are selling your medical product in the EU, you have a Notified Body (unless your product is Group 1). You should agree your production test plan with them. Be aware that they may insist on the high current earth continuity test. Good Luck, Jon Griver Medson Ltd -Original Message- From: Dick Grobner [mailto:dick.grob...@medgraph.com] Sent: Monday, May 21, 2001 18:23 To: 'Jon Griver' Cc: IEEE EMC-PSTC E-Mail Forum (E-mail) Subject: RE: Production Line Test Requirements - Medical Devices Jon Thx for the info, however, I re-checked the two known US standards (UL2601, Appendix D - Manufacturer's Responsibilities, Construction Considerations and Requirements for Factory Tests) (NFPA 99, Grounding Circuit Continuity - Measurement of Resistance). UL defines Production Line Grounding Continuity Test Equipment as: Any suitable continuity indication device (such as an ohmmeter, a battery and buzzer combination, or the like) may be used to determine compliance with Grounding Continuity Test requirements. The NFPA std is even less definitive on this matter. EN60601-1, Appendix B - Testing During Manufacture and/or Installation, Not Used. See rational to sub-clause 4.1. Which states - Tests described in this standard are type tests. I checked all of the amendments including EN60601-1 for medical systems, and I do not see anything changing this. My questions remains, where does it state to use the 10-25Amp, 50 or 60Hz @ 6Volt for 5 seconds test? Is this a carry over from another EN standard? Why wouldn't a simple continuity tests as defined by UL be appropriate from equipment coming off of the production line (assuring that the protective earth circuit in intake)? Appreciate your feedback Jon! thanks again. Does anyone else on this forum have any input - would appreciate it. --- 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: http://www.rcic.com/ click on Virtual Conference Hall,
Re: Production Line Test Requirements - Medical Devices
200105212113.oaa14...@epgc196.sdd.hp.com, Rich Nute ri...@sdd.hp.com inimitably wrote: Yes, for one strand. No, for five strands. I agree with what you say. In Europe, the PEC within equipment may be 16/0.2, so the possibility of the connection being reduced to one or two strands is, in one sense, 1 in 560, while for your 36 strand wire it is very much lower. -- Regards, John Woodgate, OOO - Own Opinions Only. Phone +44 (0)1268 747839 Fax +44 (0)1268 777124. http://www.jmwa.demon.co.uk Why not call a vertically- applied manulo-pedally-operated quasi-planar chernozem-penetrating and excavating implement a SPADE? --- 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: http://www.rcic.com/ click on Virtual Conference Hall,
Re: Production Line Test Requirements - Medical Devices
Hi John: Because continuity at low current does not ensure that the protective circuit will carry a large fault current - it might be 'hanging on by one strand'. Yes, for one strand. No, for five strands. Some years ago, I did some experiments on what problems the 25-amp test would detect. I simulated broken strands by cutting them one at a time. With five strands intact, the circuit passed the 25-amp, 2-minute test. It failed at 4 strands and 1 minute. (The tested wire was 18 AWG comprised of 36 strands of 34 AWG.) The ability of a few strands to carry the 25-amp current depends on the free length of the those few strands, which in turn determines the heat-sinking provided to those strands. The free length was on the order of 3 mm. My experiment assumed the problem was caused by an incorrectly set wire stripper, that cut a number of strands. So there was a very small free length of strands. I published this study in the Product Safety Newsletter, Vol. 10, No.1, January-March, 1997. Best regards, Rich --- 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: http://www.rcic.com/ click on Virtual Conference Hall,
Re: Production Line Test Requirements - Medical Devices
36BDBCA75E0FD411A80100104B93ABF202C2C079@MGCMAIL, Dick Grobner dick.grob...@medgraph.com inimitably wrote: Why wouldn't a simple continuity tests as defined by UL be appropriate from equipment coming off of the production line (assuring that the protective earth circuit in intake)? Because continuity at low current does not ensure that the protective circuit will carry a large fault current - it might be 'hanging on by one strand'. -- Regards, John Woodgate, OOO - Own Opinions Only. Phone +44 (0)1268 747839 Fax +44 (0)1268 777124. http://www.jmwa.demon.co.uk Why not call a vertically- applied manulo-pedally-operated quasi-planar chernozem-penetrating and excavating implement a SPADE? --- 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: http://www.rcic.com/ click on Virtual Conference Hall,
RE: Production Line Test Requirements - Medical Devices
Hi Dick, The requirement for using 10 to 25 Amps comes from the test house. It is their mark. If you want to use it, they can require you to do anything they want. Is it fair, no. Does the requirement make engineering sense, no (I believe that Rich Nute did an article on how this requirement did not identify anymore failures than the simple ohm meter did). Do you still have to do it, yes! If you are just declaring conformity for the MDD, use your risk analysis (i.e. EN 1441) to show that the risk of using a ohm meter is an acceptable one. Your NB might review it, but you should be able to switch to the ohm meter. Ned Ned Devine Program Manager III Entela, Inc. 3033 Madison Ave. SE Grand Rapids, MI 49548 616 248 9671 Phone 616 574 9752 Fax ndev...@entela.com e-mail --- 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: http://www.rcic.com/ click on Virtual Conference Hall,
RE: Production Line Test Requirements - Medical Devices
Jon Thx for the info, however, I re-checked the two known US standards (UL2601, Appendix D - Manufacturer's Responsibilities, Construction Considerations and Requirements for Factory Tests) (NFPA 99, Grounding Circuit Continuity - Measurement of Resistance). UL defines Production Line Grounding Continuity Test Equipment as: Any suitable continuity indication device (such as an ohmmeter, a battery and buzzer combination, or the like) may be used to determine compliance with Grounding Continuity Test requirements. The NFPA std is even less definitive on this matter. EN60601-1, Appendix B - Testing During Manufacture and/or Installation, Not Used. See rational to sub-clause 4.1. Which states - Tests described in this standard are type tests. I checked all of the amendments including EN60601-1 for medical systems, and I do not see anything changing this. My questions remains, where does it state to use the 10-25Amp, 50 or 60Hz @ 6Volt for 5 seconds test? Is this a carry over from another EN standard? Why wouldn't a simple continuity tests as defined by UL be appropriate from equipment coming off of the production line (assuring that the protective earth circuit in intake)? Appreciate your feedback Jon! thanks again. Does anyone else on this forum have any input - would appreciate it. -Original Message- From: Jon Griver [mailto:jo...@medson.com] Sent: Monday, May 21, 2001 9:16 AM To: Dick Grobner Subject: RE: Production Line Test Requirements - Medical Devices Dick, The requirements for production tests of medical equipment generally are: 1. Hipot at 1500AC - between live and neutral connected together and earth. 2. Earth continuity at 25A between earth pin on plug and enclosure (choose a point that may be problematic if there are manufacturing problems) 3. Earth and/or patient leakage. Whether you do both, one or neither of these tests depends on the product. As the production tests are intended to find production problems (as opposed to type tests which are intended to find design problems), choose the tests that you think make sense from the production engineering point of view. Document the reasoning behind your choice. IT equipment only requires Hipot and earth continuity tests. Hope this helps, Jon -Original Message- From: Dick Grobner [mailto:dick.grob...@medgraph.com] Sent: Monday, May 21, 2001 16:36 To: 'Jon Griver' Subject: RE: Production Line Test Requirements - Medical Devices Jon Thanks, you have confirmed what I thought I knew. We just had our annual ISO 9001 audit (2 weeks ago). One issue that one of the two auditors raised was why are you not doing the ground integrity test (25 Amp test) on 100% of your production units? I asked do you mean ground continuity (Ohm test) and he said no, the ground integrity test. That's when I started digging into the standards. UL (and the former ETL) states high potential and ground continuity tests on all production units. EN60601-1 states that all tests within this document are type tests. The auditor gave me no reference to any EN, etc. when I asked. So, I have a suspicion that this is his wish and not stated in any EN (at least that I know of so far). SO - I will continue to pursue with other outside sources (but not this one auditor!) Thanks for the reply back! PS - does ITE equipment require this test (ground integrity ((25 Amp)) test? -Original Message- From: Jon Griver [mailto:jo...@medson.com] Sent: Sunday, May 20, 2001 1:34 AM To: emc-p...@majordomo.ieee.org Subject: FW: Production Line Test Requirements - Medical Devices Dick, To the best of my knowledge there is no EN standard or guidance on production tests for medical equipment (There is a standard, EN 50116, for IT equipment). Your best bet is to discuss this with your Notified Body and to come to a mutually acceptable set of tests. Regards, Jon Griver Medson Ltd. Good Day Everyone Question I have - Does anyone out there know if an EN standard or guidance document exists that deals with production line test requirements of finished medical devices. Reading in EN60601-1 it states that the test (ground resistance, high potential, etc.) are type test only (See appendix B, and then paragraph 4.1). Thus - they are not identified as production line tests. I know that the NRTL's in the USA (UL/ETL) specifically call out what tests are to be performed after the production build of equipment. Any input would be appreciated. Thx Dick Grobner Medical Graphics Corporation 350 Oak Grove Parkway St Paul MN 55127 651-766-3395 651-766-3389 (fax) dick.grob...@medgraph.com --- 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
FW: Production Line Test Requirements - Medical Devices
Dick, To the best of my knowledge there is no EN standard or guidance on production tests for medical equipment (There is a standard, EN 50116, for IT equipment). Your best bet is to discuss this with your Notified Body and to come to a mutually acceptable set of tests. Regards, Jon Griver Medson Ltd. Good Day Everyone Question I have - Does anyone out there know if an EN standard or guidance document exists that deals with production line test requirements of finished medical devices. Reading in EN60601-1 it states that the test (ground resistance, high potential, etc.) are type test only (See appendix B, and then paragraph 4.1). Thus - they are not identified as production line tests. I know that the NRTL's in the USA (UL/ETL) specifically call out what tests are to be performed after the production build of equipment. Any input would be appreciated. Thx Dick Grobner Medical Graphics Corporation 350 Oak Grove Parkway St Paul MN 55127 651-766-3395 651-766-3389 (fax) dick.grob...@medgraph.com --- 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: http://www.rcic.com/ click on Virtual Conference Hall, --- 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: http://www.rcic.com/ click on Virtual Conference Hall,
Production Line Test Requirements - Medical Devices
Good Day Everyone Question I have - Does anyone out there know if an EN standard or guidance document exists that deals with production line test requirements of finished medical devices. Reading in EN60601-1 it states that the test (ground resistance, high potential, etc.) are type test only (See appendix B, and then paragraph 4.1). Thus - they are not identified as production line tests. I know that the NRTL's in the USA (UL/ETL) specifically call out what tests are to be performed after the production build of equipment. Any input would be appreciated. Thx Dick Grobner Medical Graphics Corporation 350 Oak Grove Parkway St Paul MN 55127 651-766-3395 651-766-3389 (fax) dick.grob...@medgraph.com --- 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: http://www.rcic.com/ click on Virtual Conference Hall,
