[R-390] Need help fixing R390A not to trip GFI breaker

[Richard Loken]

On Tue, 21 Aug 2007, Barry wrote:

> As was mentioned, the problem is in the leaky line filter capacitors.
> Here is one way I fixed that:

Once more with feeling!  Those capacitors ARE NOT LEAKY!  They are 0.1mfd
capacitors and Xc=1/2 * pi * f * C and that says:

	Xc = 1 / 2 * 3.14 * 60 * (1 x 10-7)
           = 26K ohm

	I = E/R
	I = 120 / 26000
	  = 4.6mA

and that will trip any properly working GFCI because they should trip at
between 4 and 5 mA.

Further, the manual say that the R390(A) must be grounded to protect the
operator so the line filter worked properly withing the environment in
which the R390 was expected to be used.

This diatribe is repeated by one person or another two or three times each
year whenever somebody says the capacitors in the line filter ar leaky.

"What DO they teach in those schools?" (courtesy of C.S.Lewis)

-- 
   Richard Loken VE6BSV, Systems Programmer - VMS  : "Anybody can be a father
   Athabasca University                            :  but you have to earn
   Athabasca, Alberta Canada                       :  the title of 'daddy'"
   ** richardlo at admin.athabascau.ca **             :  - Lynn Johnston