Yes, its a dual primary trafo that can be wired for 110 or 220V. I have the red and black wired together and the other red and black wired to the soft-start..
Just rigged everything down, but on the next attempt, I can try and take some more pictures in case that might reveal something obvious I've overlooked.
Well, if the relay shorts the mains, this should allso have blown the fuses with the trafo disconnected, but this doesn't happen...
Just rigged everything down, but on the next attempt, I can try and take some more pictures in case that might reveal something obvious I've overlooked.
Well, if the relay shorts the mains, this should allso have blown the fuses with the trafo disconnected, but this doesn't happen...
Sounds like you are out of phase.
Easy check:
- take a low voltage transformer, like 10vac more or less and connect a single primary winding to the secondary of the transformer. Note the secondary voltage.
- if you are using the primaries in parallel, then connect the other two primary windings to the ones already wired. (voltage stays the same)
- if you are using the primaries in series, then disconnect ONE of the two already connected primary wires, connect it to ONE of the "new" primary wires and then the other "new" primary wire to the transformer. Note the voltage. (voltage becomes 1/2)
You can also measure the current using a (~1ohm, value not critical) resistor in series with whatever side (primary or secondary) is convenient.
IF the primaries are out of phase then the transformer will draw excess current, the output voltage will be nil and it will likely hum if the little transformer isn't too tiny, and/or the little 10vac transformer will hum a lot.
Reverse the wires, make note of how they should be and re-test. The voltage should go up and the current down.
_-_-bear
Easy check:
- take a low voltage transformer, like 10vac more or less and connect a single primary winding to the secondary of the transformer. Note the secondary voltage.
- if you are using the primaries in parallel, then connect the other two primary windings to the ones already wired. (voltage stays the same)
- if you are using the primaries in series, then disconnect ONE of the two already connected primary wires, connect it to ONE of the "new" primary wires and then the other "new" primary wire to the transformer. Note the voltage. (voltage becomes 1/2)
You can also measure the current using a (~1ohm, value not critical) resistor in series with whatever side (primary or secondary) is convenient.
IF the primaries are out of phase then the transformer will draw excess current, the output voltage will be nil and it will likely hum if the little transformer isn't too tiny, and/or the little 10vac transformer will hum a lot.
Reverse the wires, make note of how they should be and re-test. The voltage should go up and the current down.
_-_-bear
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I recommend the bulb because it seems to protect and prevent fuse blowing no matter how bad the transformer mis-wire is.Good advice, but in this case it probably wouldn't have helped.
I have never damaged a transformer nor a downstream component when using the bulb.
I have blown up quite a few components when I have not used the bulb.
Well... would that be a GE lightbulb, or some other brand?? Westinghouse perhaps? Sylvania?
_-_-bear
Maybe Russian military light bulbs are the best? NOS ?
Exactly what I do, and FWIW a shorted transformer whether by defect or miswiring will result in the lamp being fully illuminated and will limit the current to the value required by the lamp rather than to what the source impedance of the mains and mains wiring will permit.
I have been an advocate of this approach for 25yrs now, and prefer it to the variac/ammeter set up Bear advocates for initial fault finding because of its inherent current limiting. I also use the lamp with variac in many instances as well.
In the USA you can get 150W+ bulbs from these guys, example 300W bulbs here: https://www.1000bulbs.com/category/300-watt-standard-shape-light-bulbs/ I've found high wattage incandescents pretty hard to source locally. You can buy in small quantities from these guys.
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I have run entire power amps at low output levels with the 200-300W bulb.
One time, I was tearing my hair out with a problem power amp prototype bound for the CES show that blew up on every turn on. My associate, a full time repair technician, that I hired to find the problem, brought his series light bulb. We found that my assembly tech FORGOT to put isolation pads on the driver devices. I now almost always use my series lamp assembly when real problems arise.
One time, I was tearing my hair out with a problem power amp prototype bound for the CES show that blew up on every turn on. My associate, a full time repair technician, that I hired to find the problem, brought his series light bulb. We found that my assembly tech FORGOT to put isolation pads on the driver devices. I now almost always use my series lamp assembly when real problems arise.
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