Capacitance between chassis and circuit common ground.

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I'm in the checkout phase of my monoblock amplifier project and I've run into a problem with one of the amps. I have about 4uf of capacitance between the chassis and the circuit's common ground. I don't really know if that is a problem but one of the negative bias supplies was taking quite awhile to charge up (the other amp took about 2 seconds to get to full voltage while the "bad" amp took nearly 10 minutes). I initially thought that the transformer was bad (a $6 magentek/triad 120V 50ma model) since the resistance of the primary legs to circuit ground measured exactly like the values measured on the good amp. Could this chassis-circuit ground capacitance be the cause of what is seemingly loading down the bias transformer? The other supplies (driver and output stage) do not seem to be affected which led me to believe that the bias trannie was the culprit.
The design of the amp has a 10 ohm resistor connecting the circuit ground and the chassis which would "short" out the capacitance but I'm still concerned as there is a discrepency between these two units which are built the same way. Even on the good unit, there is no measurable capacitance between the chassis and circuit ground when the resistor is disconnected on the good unit. There is capacitance on the bad unit with the resistor disconnected. One thing that I observed through troubleshooting was that when I disconnected the driver stage from the circuit ground and the circuit itself, the capacitance dropped to .4 uf. Is there cause for concern here or is the 10 ohm resistor there to aleviate this "problem?"
Thanks for any insight,
Tom Â§.

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Topic - Capacitance between chassis and circuit common ground. - Tom Â§. 13:44:07 11/08/99 (8)

Re: Capacitance between chassis and circuit common ground. - Dave Ingels 14:11:45 11/08/99 (7)

Re: Capacitance between chassis and circuit common ground. - Tom Â§. 14:35:19 11/08/99 (6)

Re: Capacitance between chassis and circuit common ground. - Dave Ingels 16:37:33 11/08/99 (5)

Re: Capacitance between chassis and circuit common ground. - Tom Â§. 16:58:35 11/08/99 (4)

Re: Capacitance between chassis and circuit common ground. - Shawn Harvey 08:08:34 11/09/99 (3)

Re: Capacitance between chassis and circuit common ground. - Tom Â§. 08:27:38 11/09/99 (2)

Re: Capacitance between chassis and circuit common ground. - Dave Ingels 10:03:19 11/09/99 (1)

Bingo. - Tom Â§. 10:16:31 11/09/99 (0)

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