Re: Phase loss
Secondary site of the transformer is a WHY with the star point connected to ground (neutral not used). - Original Message - From: John Shinn john.sh...@sanmina-sci.com To: 'Arno van Kesteren' avkes...@eso.org; emc-p...@ieee.org Sent: Friday, March 22, 2002 5:16 PM Subject: RE: Phase loss Delta or WYE 3-phase circuit? John Shinn, P.E. -Original Message- From: owner-emc-p...@majordomo.ieee.org [mailto:owner-emc-p...@majordomo.ieee.org]On Behalf Of Arno van Kesteren Sent: Friday, March 22, 2002 12:31 AM To: emc-p...@ieee.org Subject: Phase loss Dear All, When a circuit breaker trips on excessive ground current (250 A) and while measuring that one of the 3 phases doesn't carry any current (while the others have the same current as the protective ground) what could be the problem ? I was thinking of a sudden phase loss and would like to know how that could happen without any loose connections in the system. The system itself contains a 3-phase rectifier. Greetings, Arno van Kesteren --- 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: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@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://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list --- 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: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@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://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list --- 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: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@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://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list
Phase loss
Dear All, When a circuit breaker trips on excessive ground current (250 A) and while measuring that one of the 3 phases doesn't carry any current (while the others have the same current as the protective ground) what could be the problem ? I was thinking of a sudden phase loss and would like to know how that could happen without any loose connections in the system. The system itself contains a 3-phase rectifier. Greetings, Arno van Kesteren --- 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: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@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://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list
Temporarily disabling a fire fighting system
Dear All, Although maybe a bit out of the scope of this group I still hope that this issue may be dealt with. I would like to know whether the standards allow the installation of a switch in a fire detection fighting system to be able to temporarily disable its operation. If not, what would be the procedure to build in such functionality ? Arno van Kesteren ESO Munich, Germany e-mail: avkes...@eso.org --- 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: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@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://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list
Re: EMC and Safety PCB Reviews
Hi Alex, As a start I could give you some guidelines that may be used to encompass in your list (don't know though if all may be applicable to the EMC requirements you may envisage): . Track all signal lines on the board, avoid 'flying leads' across the board. . Ensure proper signal returns; if necessary include isolation to define preferred current paths. . Keep interference paths segregated from sensitive circuits. . Minimize ground inductance with thick gridding or ground plane(s), use power plane where possible. . Minimize enclosed loop areas in high current, high di/dt or sensitive circuits. . Minimize surface areas of nodes with high dv/dt. . Minimize HF and RF track length and component leadout length. . Use wide tracks for power lines and decouple at local boundaries (use 'low Q' RLC filters). . Avoid overlapping power planes. . If possible make tracking run orthogonal between adjacent layers. . Use track mitring (bevelling the edges at corners) and avoid track stubs. . Do not leave any floating conductor areas, if possible connect to ground plane. . On sensitive components and terminations use surrounding guard ring and ground fill, where possible. . If used, only connect the guard ring to ground at a single point and make no other use of it. . Avoid slit apertures in the PCB layout, particularly in ground planes or near current paths. Concerning safety make sure the creepage and clearance distances are conform the norms (e.g IEC 60950, 61010) Greetings, Arno van Kesteren EMC and Electrical Engineer European Southern Observatory, Munich - Original Message - From: Alex McNeil alex.mcn...@ingenicofortronic.com To: emc-p...@majordomo.ieee.org Sent: Wednesday, March 06, 2002 3:46 PM Subject: EMC and Safety PCB Reviews Hi Guys, I am being asked to review PCB's for EMC (and Safety) acceptance. I was going to try and collate a check list then I thought of this wonderful forum!! Does any kind person have such a thing as an EMC PCB Design Check list? Does any kind person have such a thing as an Safety PCB Design Check list? Kind Regards Alex McNeil Principal Engineer Tel: +44 (0)131 479 8375 Fax: +44 (0)131 479 8321 email: alex.mcn...@ingenicofortronic.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: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@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://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list --- 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: Ron Pickard: emc-p...@hypercom.com Dave Heald: davehe...@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://ieeepstc.mindcruiser.com/ Click on browse and then emc-pstc mailing list
Distance between cables
Dear forum, I would like to ask whether there is a standard / recommended practice for the minimum distance between power cables and data transmission cables like twisted pair (both shielded and unshielded). Greetings, Arno van Kesteren EMC electrical engineer European Southern Observatory
