Gonset amp blows 20 amp GFI breaker when keyed

[N3DRB The Derb]

Well, I don't know whats wrong. All tubes light, they draw static resting current of 60 ma or so, but when you plug the wall wort in the wall and key the amp, it instantly blows the 20 amp GFI breaker on the box. I used the 2 wire cord n fused plug it came with, not having any fuse holders heavy duty enough to install the 3 wire grounded AC cord I wanted to use. yaesu and amp are hooked to the same earth ground system and back to the service entrance ground, but that ground is very corroded n I doubt it is a ground at all. Power company refuses to do anything bout it.

Everything ok until the amp is keyed. Then poof. Amp not blowing the 15 amp fuses in the line. The breaker goes out. only when keyed.

then when I come back in I knock a glass bowl into my computer and now it wont boot or do anything. Dead. 

I think I am about electroed out. I'm not sure I'm mentally good enough to do this anymore. 

Anyone have any guesses?

[Ian VK3KRI]

GFI = Ground fault Isolator?

Thats probably tripping on way less than 20amps, probably mA of current differential between the two mains wires, caused by leakage to ground somewhere - OR being triggered by RF  on the mains.
Unless you've got some ground leakage that only occurs when the amps keyed, which seems unlikely if you can apply B+ happily to measure the idling current, I'd be guessing its RF setting it off.
                                                                Ian VK3KRI

[ka3zlr]

Welp,

 Knowing the latest house wiring deficiencies, (Not Strapencent enough).LOL..I'd run a seperate line just for the amplifier..IMO...

[WA2ONK]

I had a similar problem on voice peaks with my class e rig. The rig wasn't on a GFI, but it was tripping other GFI breakers in the panel. On someone's suggestion, I bypassed the hot and neutral at the GFI breaker in the panel with 2kv .01mfd.

If you're tripping a GFI outlet, try the bypassing at the outlet itself.

Chuck..

[w3jn]

You have line leakage to ground somewhere; that's what's tripping the GFI; either that, or there's RF getting into the GFI and tripping it.

Are there bypass capacitors on the line side of the amp anywhere?  Ones that might be in circuit only when the amp is keyed?

As I recall this didn't happen when we had that thang all JSed together.  Try disconnecting the wire going from your equipment to your service entrance ground (just use the ground at the plug) - this will hopefully force any RF on the line to be common mode and thus won't trip the breaker.

Also you could try reversing the walll wart and amp plugs in the wall socket.

GFIs are great for safety but can really be frustrating when dealing with stuff that has RF filtering on the line.

[WQ9E]

Does the GFI trip out at lower drive/input levels (running your Gonset amp with a bit less drive)?  I bet you are getting RF back into the GFI, my Desk KW on 75 meters will trip only one of the many GFI breakers in our master bedroom suite-I cured this by replacing that particular GFI breaker which apparently was overly sensitive to RF.  You might try a ferrite sleeve on the power cord where it exits the amplifier.

[N3DRB The Derb]

I did think of a ferrite sleeve on the ac cord - it's on there.

All AC lines in a garage have to have a ground fault interrupter breaker or it's not up to US code. It's a 20A line, with nothing else on it. I am going to try JN's suck-gestion and reference the gear to the ac mains ground and see if that cures it. Maybe I'm not a idiot after all. I was so sure I got everything right this time - and to have the thing fail like that felt like a kick to the doo dads.
 
so I should measure the ac difference between the ac mains ground and my ground system, if I see any, thats likely the culprit? Can i js a jumper between the 2 to equalize it safely?

btw it's hooked to my 500 W bird termaline so there really shouldnt be that much rf floating around, should there?

[W1DAN]

Derb:

I'd pull the plate caps of the tubes or pull the tubes. This should eliminate any RF to see if RF or DC is the problem.

Also, isolate the amp from all else (like the transmitter and load) and see if you still trip the GFI.

I am thinking it may be a power supply pulse...maybe a bypass cap on the DC creating ground current pulse for a moment....

Just a stab in the dark.

Good Luck,
Dan
W1DAN

[flintstone mop]

Let's cut to the chase and connect all your radio stuff to a non-GFI waste of time receptacle. Those are only good for working with electrical things outside or power tools, where you might get involved with water. I never saw anything useful for them. THey cause more problems than they are worth. Another overprotective paranoid thought from bored engineers.
Fred

[Opcom]

I got rid of the ones on my truck-mounted diesel generator. The truck was set up for 3-phase wye, and so has has the neutral and chassis ground STRAPPED together in such a solid way that the only way to get a buzz is to get ahold of the hot wire. Get rid of the GFI's and ground the equipment well to both the wall plug ground and the earth ground. In order to avoid the odious codes, install a 120V/30A twist-lock or 240V socket which should not require such an inconvenience, and route that to your distribution rack.

[N3DRB The Derb]

posted new photos of my deal in the station links and photos section.

[WBear2GCR]

Should you happen to have a reasonably large sized isolation transformer lying about, try that?

I like the suggestion of keying the linear without any RF going in to it, I'd be cautious about keying it with the plate caps disconnected, it might exceed the peak rating of the PS filter caps... might not.

A variac inline just turned up enough to permit the keying relay to pull in will limit the current and the inductance of the variac might reduce the keying pulse...

The  stupid GFI (= Ground Fault Interrupter) is likely seeing the difference between the neutral of the two wire line cord and the "ground" being the thoid pin... so maybe string a wire between the third pin (bannana plug?) and the ground lug on the Lyn-eee-ar?? That might make it happy seeing the same thing on both lines...

              _-_-bear

[KA1ZGC]

The  stupid GFI (= Ground Fault Interrupter) is likely seeing the difference between the neutral of the two wire line cord and the "ground" being the thoid pin...

Which goes to show you that if GFCI breakers had existed when Old Buzzard George was building rigs, the world would be a very different place.

Just yank the breaker (caw mawn) and put a real one in there. Unless you plan on operating Bathtub Mobile, the GFCI breaker gains you absolutely nothing. Move it over to your kitchen or bathroom circuit and be done with it.

--Thom
King Abraham One Zebraham George Charlie

[N3DRB The Derb]

ok now we getting someplace. unplugged cheap lakewood ac heater from socket across the room, amp keys no problem! click clunk. clink clunk. music to my ears. Breaker stays on NP.

when not keyed amp reads about 30 ma current, when keyed it goes up to maybe 70 or so.

but Yeasu does not seem to like amp - weird final dip and no drive. no output from amp. taking the case back off the amp now....maybe T/R relay wiring got confused...that is to say, I got confused?

case dont go back on until it works FB this time. Thanks for the input everyone. I needed it. Now gotta see whats going on in there.

[k4kyv]

I had considered installing some arc-fault breakers in the house, to add protection in case of failure somewhere in our ancient house wiring.  But those things are designed to trip from the rf generated by an arcing loose connection, so I'm afraid I would be opening a real can of worms trying to get them to function in an rf environment. 

That ancient wiring was soldered together, so I suspect it is less likely to arc than new work which is nearly always connected together with wire nuts.  I have seen wire nut connections literally fall apart because the wire nuts were not installed properly.

I am not so paranoid about dead shorts, which would be the greatest likelihood of failure in our old wiring but at least they can be expected to pop the breaker.  Arcs caused by loose connections are very dangerous because they can get very hot, without blowing a conventional breaker, since they tend to cause the circuit to pull less current instead of more.

I recently had the main breaker to heat up as a result of poor internal contact.  I got a new breaker, but the conducted heat had ruined the insulation on the last two feet of the main wire coming in from the meter.  I had to hire an electrician to repair it, since I had no way to cut the power coming into the box without physically pulling the meter.

[N0WEK]

When I need to work on the main wiring at the box I just cut the seal and pull the meter. I've never had a complaint from the power company, they just put a seal back on it when they notice, and since they now read it remotely it'll usually be months before they notice. I suspect that they do look at my power usage and see that it hasn't changed.

[N3DRB The Derb]

update: the open frame T/R relay in the amp was not making proper contact on either RF in or RF out. usually it would make or break one one side or the other but not both at the same time. We bought a direct replacement at the Richmond HamFest for 1 dollar ( actually, a much better unit with all ceramic insulation from Leach Relay Co. ) and are installing it now.

Actually, it's nap time. magic anti-shake rattle and rock and roll drugs are taking over my body as they do about this time every day. 

[WA1GFZ]

Don,
I just repaired some wiring in my Dad's 50 year old house. He had a loose connection in a switch box due to a loose crimp. This convinced me that every joint in the new QTH will be soldered then a wire nut installed. It takes a lot of extra time but I'll feel better. I did a circuit this past weekend and all the bare copper needed to be polished due to tarnish from the salt air.
NEC isn't tuff enough for me.

[AB3L]

That ancient wiring was soldered together, so I suspect it is less likely to arc than new work which is nearly always connected together with wire nuts.  I have seen wire nut connections literally fall apart because the wire nuts were not installed properly.

The wirenuts are the finished product. They are installed after a wiring joint has been successfully twisted together with a pair of square nosed pliers. The increased laziness of a growing percentage of todays mechanics makes this last step a matter of "time is money" mentality. Then the laziness takes the next step when they don't pull on the wires to see if they will stay under the wire nut. In my line of work I have pulled wiring out of Jboxes and had them fall apart under load. That will wake you up.

[K3ZS]

When I wired my house I borrowed a crimping tool.    After twisting the wires together, you placed a copper ferrule over the wires and used the tool to squeeze a hexagonal crimp over the wires.    Then a plastic cap, that was made for this purpose, was snapped over the connection.    I haven't seen this in use since then, I use wire nuts now.

[W1RKW]

I think this #14 wire you get from Home Cheapo and Lowes is not #14.  It is thinner.

I installed a small air compressor a few years ago in the garage.  It was rated for 15A 100VAC service or at least I thought.  When it would start sometimes it would start sometimes it would not.  When it would not start and sit there and hum away the garage lights would dim to half brightness, not a good situation.  Since the house was new I figured they did a crappy wiring job on that circuit and went around tightening outlets and what not. That did not help.

To make a long story short I ended up running separate 20A circuit with todays #12 to the work area.  Solved the problem.  But in doing so I compared the #12 wire I bought for the circuit to the old roll of #14 wire I had from my old place.  In comparison they were nearly the same thickness and stiffness. 

I always thought the newer #14 wire I had purchased in the past was much lighter and easier to bend than the the old wire in my previous home.  Sure enough it was when I made the comparison. 

I don't know how they can pass off todays #14 as #14 because it ain't.  I know if I ran a length of the old #14 I have on hand that compressor would kick off without a flinch.

[KB2WIG]

  '  don't know how they can pass off todays #14 as #14 because it ain't. "

Must be that the old stuff is O₂ free...........  klc

[k4kyv]

I think this #14 wire you get from Home Cheapo and Lowes is not #14.  It is thinner... I compared the #12 wire I bought for the circuit to the old roll of #14 wire I had from my old place.  In comparison they were nearly the same thickness and stiffness. 

I always thought the newer #14 wire I had purchased in the past was much lighter and easier to bend than the the old wire in my previous home.  Sure enough it was when I made the comparison. 

I don't know how they can pass off todays #14 as #14 because it ain't.  I know if I ran a length of the old #14 I have on hand that compressor would kick off without a flinch.

Same with lumber dimensions.  If I start a project on the house, then put it on hold for a year or so, inevitably, when I return to the project, if I have to buy some more timber, the newer stuff is ever so slightly smaller than what I used before, just enough that it isn't compatible without shimming and trimming. 

At our local Lowe's, in the plywood section, what used to be 1/2" is now tagged as "approximately 1/2", 15/32".  All the other thicknesses are likewise trimmed down about 1/32".  Only the expensive, finished on both sides, furniture grade plywood is the true dimension.

Not only are we now being charged through the arse to buy this crap, but we are not even getting what we paid through the anal canal for.

[AF9J]

I think this #14 wire you get from Home Cheapo and Lowes is not #14.  It is thinner.

I installed a small air compressor a few years ago in the garage.  It was rated for 15A 100VAC service or at least I thought.  When it would start sometimes it would start sometimes it would not.  When it would not start and sit there and hum away the garage lights would dim to half brightness, not a good situation.  Since the house was new I figured they did a crappy wiring job on that circuit and went around tightening outlets and what not. That did not help.

To make a long story short I ended up running separate 20A circuit with todays #12 to the work area.  Solved the problem.  But in doing so I compared the #12 wire I bought for the circuit to the old roll of #14 wire I had from my old place.  In comparison they were nearly the same thickness and stiffness. 

I always thought the newer #14 wire I had purchased in the past was much lighter and easier to bend than the the old wire in my previous home.  Sure enough it was when I made the comparison. 

I don't know how they can pass off todays #14 as #14 because it ain't.  I know if I ran a length of the old #14 I have on hand that compressor would kick off without a flinch.

Hmmm,

It depends too Bob, on whether it's #14 for auto use, or #14 for home use.  I found that out at  an ACE harware a year ago or so.  They had two different rolls of #14 wire.  One was listed for home wiring, and the other one was listed for car wiring.  The car wiring roll was visibly smaller diameterwise.

73,
Ellen - AF9J

[WQ9E]

Don,

This is a real pain for woodworkers!  I have several specialty cutters for my shaper intended to make parts to interface with plywood and even some of the so called furniture grade stuff varies in thickness from what it is rated.  For most stuff I use "real wood" and plane it to the proper thickness but plywood does have the nice property of being fairly stable due to its plys oriented in opposing fashion; too bad the size standards are not also stable.

Rodger WQ9E

 

Same with lumber dimensions.  If I start a project on the house, then put it on hold for a year or so, inevitably, when I return to the project, if I have to buy some more timber, the newer stuff is ever so slightly smaller than what I used before, just enough that it isn't compatible without shimming and trimming. 

At our local Lowe's, in the plywood section, what used to be 1/2" is now tagged as "approximately 1/2", 15/32".  All the other thicknesses are likewise trimmed down about 1/32".  Only the expensive, finished on both sides, furniture grade plywood is the true dimension.

Not only are we now being charged through the arse to buy this crap, but we are not even getting what we paid through the anal canal for.