[R-390] added the IEC line filter

[Roy Morgan]

At 03:08 PM 11/3/2005, Tim  Shoppa wrote:
>If I look at my non-R390A rigs (mostly dating from the 50's and
>60's) ...t generally the AC hot-to-ground current through the filter cap
>is circa 1 or 2 mA so they do not trip the GFCI by themselves... but in 
>concert they do!

Tim and others,

The solution to this is to connect the line bypass caps as follows:

One from hot (black line cord wire) to neutral (white line cord wire)
One from neutral to chassis.

This way,
1) the capacitive current is from line to neutral, and the current from 
neutral to chassis is *very* small.
2) Failure of any cap will result in a safe situation: a line to netural 
short will either dis-assemble the cap (POW!), blow the fuse if the cap is 
after the fuse, or trip the house circuit breaker.  A neutral to chassis 
short will do nearly nothing.

Roy


- Roy Morgan, K1LKY since 1959 - Keep 'em Glowing!
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