Its exactly the in-rush current they are worried about. Unfortunately, I don't have the standard for the connectors so I can't tell you what the test scenario is, but I would agree that depending on the reactance of the load the inrush current could vary significantly. If the test is done on the finally sample then it is inserted 50 times and the connectors are inspected, but again I don't know the parameters for a standalone component test. Gary
-----Original Message----- From: Chris Maxwell [mailto:chris.maxw...@nettest.com] Sent: Monday, June 25, 2001 4:58 AM To: 'Tania Grant'; emc-p...@ieee.org Subject: RE: Hot Swappable Power Supplies ? I'm curious... How is in-rush current handled for these connectors? Seems like it would be somewhat easy to specify that a connector is good for hot swapping a device that draws "X" Amps of current. It's the in-rush that would be hard to quantify. One device that draws "X" Amps of current could draw "2X" in-rush current, while another device that draws "X" Amps of current could draw "50X" in-rush current. I have seen instances where large in-rush currents can burn connector contacts or even weld relay contacts together. Are the connectors rated for steady state only? Are they rated for steady state and maximum in-rush? If they are rated for steady state, is a maximum in-rush assumed? Or, alternatively are the power supplies already required to be in-rush limited. I know curiosity killed the cat, but it also improved its quality of life. Chris > -----Original Message----- > From: Tania Grant [SMTP:taniagr...@msn.com] > Sent: Saturday, June 23, 2001 1:59 AM > To: Gary McInturff; 'wo...@sensormatic.com'; emc-p...@ieee.org > Subject: Re: Hot Swappable Power Supplies ? > > Gary, and all, > > In my experience, the only sure way is to request the UL Report and read > the Conditions of Acceptability very carefully, as well as the connector > rating. I have seen connectors derated by UL and the company never > changed their spec sheets or catalog (well, maybe now, after 7 years, they > have changed them!). Also, some companies are sloppy with their > specifications;-- not every connector or pin is rated for "current > interruption" even while their page seems to imply that the whole series > is so rated. Guess what, just a handful are rated for current > interruption. > > My best advise is, if you like what you see, call the manufacturer and pin > them down. Then, when they tell you which parts are rated for current > interruption, and you still like what you see, then you have them send you > the UL report. Absolutely required, or you may be sorry. (You guys > don't want to hear another story how I was almost sorry, but because of > sheer luck managed to stumble on the fact that the connector that was > being designed in was NOT rated for current interruption. I emerged a > hero, but I was quacking in my sandals how close I came to blowing the > whole thing!) > > Tania Grant > taniagr...@msn.com <mailto:taniagr...@msn.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 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://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 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://www.rcic.com/ click on "Virtual Conference Hall,"
