PLEASE NOTE: If you had an account with the previous forum, it has been ported to the new Genetry website!
You will need to reset the password to access the new forum. Click Log In → Forgot Password → enter your username or forum email address → click Email Reset Link.
I tested it the way Sean did in his testing FETs video. Positive on the left most leg and negative on the heatsink. On his video he shows around 1.9 v on good FETs installed on the unit.
Cleaned up nice after a good long ultrasonic cleaning and 2 hours in the oven to dry.
I think may have found my issue. Visually the tranny looks good but when measuring resistance from black to yellow I have 0.000 ohms resistance. Looks like I have a dead short between windings.
Does anyone know the resistance values of a good AS2 transformer? Or have a schematic?
Nevermind, having a brain fart...have good resistances on the outputs, thought the inputs were separate.
Was gonna say...all of the coils' resistance should be too low to read with a regular DMM. I've "ohmed-out" several PJ trannies by using a constant-current power supply, measuring the voltage drop, and doing Ohm's Law to determine the resistance (usually quite a bit less than one ohm).
As long as the "FET" side is isolated from the "output" side, it should be alright.
One way to determine whether or not the tranny is at fault would be to reverse-power the transformer for a test (if completely disconnected), by applying 120vAC to one of the output phases (L1 - N, or L2 - N); it will autoformer 240v across L1-L2, and should provide ~35-36vAC on the other coil that goes to the FETs. Should be well under 0.5A current drawn from the AC line. If it draws a huge amount of power...then the tranny is at fault.
PLEASE NOTE: WORKING WITH AC MAINS VOLTAGES CAN BE VERY DANGEROUS! Try at your own risk. You have been warned 😉.
Hrm...I only have 4 sets of wires on my as2.. a big black bundle, a big yellow bundle, and a red and black wire to the charge board...I'm presuming you'd want to power the red and black then measure the output on the yellow and black bundles....this isn't a split phase transformer.
Ah, I just assumed it was a split-phase transformer, my bad.
So you would be correct, yes, power red and black, and measure output on yellow/black bundles. No-load current on the AC line should be well under 0.25A--if much more than that, the tranny is internally shorted.
Ok, transformer is good. Amperage is too low to read by my clamp meter and it outputs 8 volts.
Ok, transformer is good. Amperage is too low to read by my clamp meter and it outputs 8 volts.
Outputs 8v? Is this a 12v inverter?
*doh* went back to your photo, there's a "12v" stamp on the board. That's the right output from the tranny then.
So I'm at a loss at this point. FETs test out good off the unit. Replaced every component except the charge board and main board with the ones I ordered from Gentery. Guess I'll just have to toss it and start over.
If this is inverter has a single-phase 120v transformer, it's possible the boards are wrong for that--and it's overdriving trying to get 240v output. At 12v, that'll be impossible--but it'll run ridiculous no load current + sound nasty. However, the output voltage likely will be somewhere past 160vAC. Sounded like you measured the proper 120v though.
It's running at 136 volts. My battery setup for testing limits it as it's just a 220 ca lawn mower battery. Can't fry anything if it can't supply the amperage lol.
It pulls the battery down under 10 volts immediately upon turning it on.
This sounds extremely highly suspect that the replacement board is expecting to regulate 240v out, and you have a 120v single-phase transformer--so it's running to redline trying to get 240v. Battery sag is preventing it from getting any higher than the 136v you're getting. This would be a control board issue...unfortunately, it's not marked as such, nor is it easy to change. Maybe the old control board would work, with the new driver?