RE: Question: Discharge capacitance 0.1 uF

2002-09-20 Thread John Allen
Woodgate [mailto:j...@jmwa.demon.co.uk] Sent: 19 September 2002 16:51 To: emc-p...@majordomo.ieee.org Subject: Re: Question: Discharge capacitance 0.1 uF I read in !emc-pstc that John Allen john.al...@era.co.uk wrote (in BFE68AB0084CD311B4FB00508B014C8703CF9BEE@MERCURY) about 'Question: Discharge

RE: Question: Discharge capacitance 0.1 uF

2002-09-20 Thread Gregg Kervill
: emc-p...@majordomo.ieee.org; emc-p...@majordomo.ieee.org; emc-p...@majordomo.ieee.org; emc-p...@majordomo.ieee.org; emc-p...@majordomo.ieee.org; emc-p...@majordomo.ieee.org; emc-p...@majordomo.ieee.org; emc-p...@majordomo.ieee.org Subject: RE: Question: Discharge capacitance 0.1 uF Gert Thanks

RE: Question: Discharge capacitance 0.1 uF

2002-09-20 Thread Gregg Kervill
-p...@majordomo.ieee.org; emc-p...@majordomo.ieee.org; emc-p...@majordomo.ieee.org; emc-p...@majordomo.ieee.org; emc-p...@majordomo.ieee.org; emc-p...@majordomo.ieee.org; emc-p...@majordomo.ieee.org; emc-p...@majordomo.ieee.org Subject: RE: Question: Discharge capacitance 0.1 uF Gert Thanks

Re: Question: Discharge capacitance 0.1 uF

2002-09-20 Thread Rich Nute
Hi Tom: So, for voltage up to 450V d.c. (i.e. up to 318V a.c.), capacitor up to 0.1uF will become a Limited Current Circuit, hence the voltage is not Hazardous Voltage (1.2.8.4) - no additional condition would be required for the capacitor connected to the primary circuit.

Re: Question: Discharge capacitance 0.1 uF

2002-09-19 Thread T.Sato
On Fri, 6 Sep 2002 16:19:52 +0900, Michael Jang mich...@certitek.com wrote: I have a question for Discharge of capacitors in the primary circuit' (Related to 60950 standard) Standard Equipment is considered to comply if any capacitor

RE: Question: Discharge capacitance 0.1 uF

2002-09-19 Thread John Allen
] Sent: 18 September 2002 19:07 To: 'John Allen'; emc-p...@majordomo.ieee.org Subject: RE: Question: Discharge capacitance 0.1 uF Hi All, From personal experience I can tell you that the involuntary reaction to a shock can have serious consequences to the sales of a company. In a former life

Re: Question: Discharge capacitance 0.1 uF

2002-09-19 Thread Warren Birmingham
Many line filters do indeed have a bleeder resistor built in. There are a few which do not, and I am familiar with one Delta filter that does not. We added the bleeder across the terminals of the filter and it was approved by UL. It just has to be done in accordance with accepted

Re: Question: Discharge capacitance 0.1 uF

2002-09-19 Thread Rich Nute
Hi Tom: So, for voltage up to 450V d.c. (i.e. up to 318V a.c.), capacitor up to 0.1uF will become a Limited Current Circuit, hence the voltage is not Hazardous Voltage (1.2.8.4) - no additional condition would be required for the capacitor connected to the primary circuit.

RE: Question: Discharge capacitance 0.1 uF

2002-09-19 Thread Gert Gremmen
Subject: RE: Question: Discharge capacitance 0.1 uF Hi Charles, Warren Seems that a few of us know what DOES happen and the longterm results, but quite a few others don't believe that it does - and that even it does then it is not very important. The difference between reality and theory! I

RE: Question: Discharge capacitance 0.1 uF

2002-09-19 Thread John Allen
-367102 (Fax) -Original Message- From: Gert Gremmen [mailto:g.grem...@cetest.nl] Sent: 19 September 2002 11:57 To: John Allen Cc: emc-p...@majordomo.ieee.org Subject: RE: Question: Discharge capacitance 0.1 uF Hi John, Even theory has to comply with practice, so i took my soldering iron

RE: Question: Discharge capacitance 0.1 uF

2002-09-19 Thread Cortland Richmond
(the unplugging process may need to be repeated a few times until the capacitor is disconnected when the mains is high at the time of disconnection and so gets a decent charge!) At a former employer, we monitored the wave form with a 'scope, and repeatedly opened and closed the connection to

Re: Question: Discharge capacitance 0.1 uF

2002-09-19 Thread John Woodgate
I read in !emc-pstc that John Allen john.al...@era.co.uk wrote (in BFE68AB0084CD311B4FB00508B014C8703CF9BEE@MERCURY) about 'Question: Discharge capacitance 0.1 uF' on Thu, 19 Sep 2002: Now, maybe, the standards writing committees will begin to take this issue on board and do something about it

RE: Question: Discharge capacitance 0.1 uF

2002-09-19 Thread Peter Tarver
John - I respectfully disagree that the standards bodies need to do anything. It is the designers that must be aware of the advancements of technology (such as described by Gert) and update their practices accordingly. [Low ESR / High Q caps are a good thing.] While I have no doubt about the

RE: Question: Discharge capacitance 0.1 uF

2002-09-19 Thread John Allen
] Sent: 18 September 2002 19:07 To: 'John Allen'; emc-p...@majordomo.ieee.org Subject: RE: Question: Discharge capacitance 0.1 uF Hi All, From personal experience I can tell you that the involuntary reaction to a shock can have serious consequences to the sales of a company. In a former life

RE: Question: Discharge capacitance 0.1 uF

2002-09-19 Thread John Allen
-367102 (Fax) -Original Message- From: Gert Gremmen [mailto:g.grem...@cetest.nl] Sent: 19 September 2002 11:57 To: John Allen Cc: emc-p...@majordomo.ieee.org Subject: RE: Question: Discharge capacitance 0.1 uF Hi John, Even theory has to comply with practice, so i took my soldering iron

RE: Question: Discharge capacitance 0.1 uF

2002-09-19 Thread Gert Gremmen
Subject: RE: Question: Discharge capacitance 0.1 uF Hi Charles, Warren Seems that a few of us know what DOES happen and the longterm results, but quite a few others don't believe that it does - and that even it does then it is not very important. The difference between reality and theory! I

Re: Question: Discharge capacitance 0.1 uF

2002-09-18 Thread Warren Birmingham
Many line filters do indeed have a bleeder resistor built in. There are a few which do not, and I am familiar with one Delta filter that does not. We added the bleeder across the terminals of the filter and it was approved by UL. It just has to be done in accordance with accepted

RE: Question: Discharge capacitance 0.1 uF

2002-09-18 Thread Gert Gremmen
Hi John, Though you are fully right theoretically, i think parts of your story are a bit overdone. Most people do not make a habit-of-disconnecting-their-heavy-equipment-while carrying-it-over-their-feet-at-the-mains-voltage-phase-point-of-90-degrees-w hile-actively-seeking- both

RE: Question: Discharge capacitance 0.1 uF

2002-09-18 Thread Grasso, Charles
Hi All, From personal experience I can tell you that the involuntary reaction to a shock can have serious consequences to the sales of a company. In a former life - a previous employer OEM'd a PC from a Korean Company. The PC had all the relevant marks but somehow the resistor that was

RE: Question: Discharge capacitance 0.1 uF

2002-09-18 Thread T.Sato
On Wed, 18 Sep 2002 13:11:23 +0100, Barker, Neil neil.bar...@e2vtechnologies.com wrote: The answer to this one is simply that for capacitances up to 0.1 uF, and for voltages up to the maximum mains supply voltage covered by the standard, the stored energy is sufficiently low as to be

Re: Question: Discharge capacitance 0.1 uF

2002-09-18 Thread T.Sato
On Fri, 6 Sep 2002 16:19:52 +0900, Michael Jang mich...@certitek.com wrote: I have a question for Discharge of capacitors in the primary circuit' (Related to 60950 standard) Standard Equipment is considered to comply if any capacitor