Solving GFCI trip problem

[AB2EZ]

I have a GFCI outlet in my basement, that feeds three outside outlets.

I was having a problem of GFCI tripping when I transmitted on various HF bands (I am forced to use an indoor doublet antenna due to CC&Rs)

I verified that removing the cables to the outdoor outlets, from the load side of the GFCI, eliminated the problem.

I verified that the GFCI trips when a 22k ohm resistor is placed between the hot and ground terminals of the GFCI outlet. (120Vrms/22k ohms = 5.5ma rms)

I verified that the GFCI does not trip when I placed a .01uF 5000V disc capacitor (-j265k ohms at 60Hz) between the hot and ground terminals of the GFCI outlet.

I then added a .01uF 5000V disc capacitor between the load side hot and the ground terminals of the GFCI outlet, and another .01uF 5000V disc capacitor between the load side neutral and ground terminals of the GFCI outlet. These bypass the common mode RF currents flowing through the losd side hot and neutral wires around the GFCI's common mode current detector circuitry.

The tripping problem is cured.

I added the capacitors by using a 3-prong plug... plugged into one of the sockets of the ground fault interrupter outlet. I was (of course) careful to PROPERLY INSULATE the wires of the capacitors from each other... and from being touched by anyone.

Stu

[WQ9E]

Stu,

Thanks for posting this info.  I went through a similar problem a few years ago with one of the GFCI circuits in our master suite which would sometimes trip when I operate 75 meter AM.  In my case placing a split ferrite core over the line near the outlet was sufficient to cure the problem but I bet you had a lot higher RF level on your circuit given the inside antenna.

[Jim, W5JO]

I have several of those in my home both outside and inside near water but have never had a problem with them tripping on any band up to 10 meters.

I wonder if the later versions are better able to withstand the situation than the older versions or are those you have older than mine?  The ones I have are about 3 years old.  I also have Eaton AFCI breakers for the bedrooms, one of which, the station is located and they never break either.

[KD6VXI]

I worked for a local REIT  not too long ago that required us to replace EVERY switch,  plug and fixture in every house we remodeled.

As such,  you can imagine I've a HUGE stash of GFI outlets.

As a test,  I've wired my entire shop with GFCI outlets.

At up to 170 watts pep,  on ten meters,  I have ZERO issue with them tripping.

I ensured I used a different brand for every box,  where I could.   Each one (sans 1, iirc)  has been a 20 amp unit.   I was going to wire the test bench with the 15s, but haven't gotten around to it.

I'll be wiring the 220 feeder probably this week,  and then I'll be able to go qro.

I have WAY more problems with AFCI  breakers over gfi.

Anything over 15 watts to 30 watts (freq dependant)  will trip them.

I did find a fix for them,  too.   See pic.

AFCI is a known issue.   Cutler Hammer realizes thus and has new rfi proof breakers available.

I'll let people know what I find when I go QRO.

--Shane
KD6VXI

[N2DTS]

I used to trip the ones in the kitchen, which is right under the 40 meter dipole center, 35 or 40 feet up.
I put a ferrite core on the microwave oven cord and have not tripped it since.
Thanks for the cap tip.

[Jim, W5JO]

I run QRO, from 1200 PEP AM and 1500+ on SSB, here Shane without a trip on the Eaton AFCI.  Wonder what the difference is?

[WA2SQQ]

I've got a similar situation. Do the caps really need to be 5kv rated? I've got some 1 kv.

I have a GFCI outlet in my basement, that feeds three outside outlets.

I was having a problem of GFCI tripping when I transmitted on various HF bands (I am forced to use an indoor doublet antenna due to CC&Rs)

I verified that removing the cables to the outdoor outlets, from the load side of the GFCI, eliminated the problem.

I verified that the GFCI trips when a 22k ohm resistor is placed between the hot and ground terminals of the GFCI outlet. (120Vrms/22k ohms = 5.5ma rms)

I verified that the GFCI does not trip when I placed a .01uF 5000V disc capacitor (-j265k ohms at 60Hz) between the hot and ground terminals of the GFCI outlet.

I then added a .01uF 5000V disc capacitor between the load side hot and the ground terminals of the GFCI outlet, and another .01uF 5000V disc capacitor between the load side neutral and ground terminals of the GFCI outlet. These bypass the common mode RF currents flowing through the losd side hot and neutral wires around the GFCI's common mode current detector circuitry.

The tripping problem is cured.

I added the capacitors by using a 3-prong plug... plugged into one of the sockets of the ground fault interrupter outlet. I was (of course) careful to PROPERLY INSULATE the wires of the capacitors from each other... and from being touched by anyone.

Stu

[AB2EZ]

I was focusing on the dissipation associated with the 120VAC, 60Hz voltage that will be across the hot-to-safety ground capacitor. I picked the 5kV disk capacitors because I had some on hand. I verified that the capacitors were not getting noticibly warm.

1000VDC rated capacitors can handle the peak voltage (120V x 1.414)... but apply 120VAC across one...  and carefully verify that it isn't getting warm.

See my last comment in your recent thread on this subject.

Stu

[KB2WIG]

R,

 I noticed your search for caps in the 'Wanted' section. You may find the related links to be of interest.

http://www.mouser.com/new/vishay/vishayVY2caps/

http://www.mouser.com/ProductDetail/Vishay-Cera-Mite/440LD10-R/?qs=sGAEpiMZZMuFb27%252bLdJAU9EQPMC8sFaI


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