Toasted 400 still toast

OK so all went well everything was where it should be still with the DBT in line so I installed the DC circuit protector and all went well with that. I took the DBT out and plugged direct into my veriac and took it up slowly all was going good till I hit 120V at 120V the DC protector tripped. I noticed the right output went up to 1.23V.... I shut it down and powered it back up bringing the voltage up slowly stopping from time to time to check output voltage and all was good.... at 115V the right output rises from .0001V to .0002V but the second I turn the veriac up to 120V the output on the right side climbs to 1.23V and the DC protector tripps... the left channel seems to be good even at 120V output remains .0001 so the problem is in the right channel
 
You thinking the variac may be off Lee? I thought that to at first and tested it with my meter it seems ok, but tomorrow morning I will try that anyway, I am dead tired right now but don't have much going on tomorrow at all....
 
Another thing I was thinking to is the problem seems to be only on the right side the left side says at .0001V on the output which has been consistent all the way through reassembly and testing as I went....
 
Mine are 122.7...right off the mains monitor on the AP...
 
Cmon bro, me or Lee will build you a 700 WOPL so you can have fun instead of letting smoke out of the magic cans..... I got 4 or 5 sitting here ready to build
 
Na, I'm only a couple miles from the power plant....
 
Here are some numbers that I am getting....

I have 120.91V coming out of the wall outlet here

First I powered up on the veriac set at 115V the DCP contacts DO close and stay closed

Left side......
Output (on backplanes) .0001V
Bias .3510V
Offset .0001V

Right side....
Output (on backplanes) .0001V
Bias .3517V
Offset .0001V

Then I plugged direct into the outlet the contacts on the DCP DID NOT close

Left side....
Output (on backplanes) .0005V
Bias .3580V I did not readjust the bias for this test this is where the bias was set to run at .3510V @ 115V power input
Offset .0002V

Right side....
Output (on backplanes) 1.94V
Bias .211V I did not readjust the bias for this test this is where the bias was set to run at .3567V @ 115V power input
Offset 1.76V

I think it has to be something in the control board on the right side as I did run it up to 120V on veriac with just the backplanes in and all was well but @ 120V with the control board in and I have a problem....
 
WOPL Sniffer said:
Cmon bro, me or Lee will build you a 700 WOPL so you can have fun instead of letting smoke out of the magic cans..... I got 4 or 5 sitting here ready to build
Click to expand...

Perry if I could I would but we are in a bit of a financial struggle over the past couple of years.... wife had to have major surgery almost lost her but the bill is more than we have left on our house to pay it off (24 more payment and we own it), money is just not coming in just barely to keep up, my truck is not even on the road hasn't been registered for a year and a half now it needed major repair, got some of it done but a bit more to go.... and on and on so a 700 is just not doable now
 
I hear ya.... I retired early and if it wasn't for my military retirement, I would be building boxes to live in.
 
roccus said:
Here are some numbers that I am getting....

I have 120.91V coming out of the wall outlet here

First I powered up on the veriac set at 115V the DCP contacts DO close and stay closed

Left side......
Output (on backplanes) .0001V
Bias .3510V
Offset .0001V

Right side....
Output (on backplanes) .0001V
Bias .3517V
Offset .0001V

Then I plugged direct into the outlet the contacts on the DCP DID NOT close

Left side....
Output (on backplanes) .0005V
Bias .3580V I did not readjust the bias for this test this is where the bias was set to run at .3510V @ 115V power input
Offset .0002V

Right side....
Output (on backplanes) 1.94V
Bias .211V I did not readjust the bias for this test this is where the bias was set to run at .3567V @ 115V power input
Offset 1.76V

I think it has to be something in the control board on the right side as I did run it up to 120V on veriac with just the backplanes in and all was well but @ 120V with the control board in and I have a problem....
Click to expand...

Hi Ray
Report the bias readings off the backplane test points, there are 2 of them on each backplane, yellow in color. Negative lead of the DVM to the output test point (gray) on the backplane board and the positive DVM lead to each of the two yellow test points. Record them and ensure that they are very close to each other but opposite polarity.

The reading on the control board only is the positive side bias reading, the backplane gives you both a positive and negative reading as each half of the output tree has its own bias reading.
 
Good evening Joe here are the results, I was not sure if you want these @ 115V or 120V so I did it at both

@115V from veriac on BP bias test points
Left side + .3454 & - .3455
Right side + .3467 & - .3462
DCP contacts are closed

@120V from veriac on BP bias test points
Left side + .3528 & - .3523
Right side + .3491 & - .3478
DCP contacts open
 
That appears quite normal Ray, the bias did not jump in these readings like it did in the earlier post. Odd. Have you posted pics of your DCP board?
 
So offset of 1.76V on one channel, or the DCP contacts opening up at 120V going into the plug is not a concern?? Not sure what kind of pic would you like??
cb1.JPG
 
These new numbers were done different than the first numbers.... the first numbers on the back plane out out was with the meter neg lead on the neg pin and the pos lead on the output pin of the back plane boards... also the earlier bias numbers were from the control board not the back plane boards
 
Just went and took these pics for you Joe...
ca1.JPGca2.JPGca3.JPG
 
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