How to test ac transformer secondary output?

[JimBanville]

Can someone please look at this photo and tell me how I would test the voltage of the 6 wires coming out of this ac transformer? Thanks!!

[R_J]

Re: How to test ac transformer secondary output?

The black should be the center tap of the purple and green wires, so you can check the voltage between the purple and green for the full secondary voltage or check between black and either purple or green.
I would need to see the bottom of the pc board to be sure that the black is the center tap. The other set of wires should be checked the same way (Red center tap?)

I said this before I saw the circuit board, so this is not correct in this case.

The Blue wire is the center tap and the Red and Brown feed the diodes.
The Black feeds a diode for a negative voltage so it is likely that either Green or Purple goes to ground and the other feeds another diode somewhere?

[JimBanville]

Re: How to test ac transformer secondary output?

The black should be the center tap of the purple and green wires, so you can check the voltage between the purple and green for the full secondary voltage or check between black and either purple or green.
I would need to see the bottom of the pc board to be sure that the black is the center tap. The other set of wires should be checked the same way (Red center tap?)

Thanks! This picture should be a mirror image of the top of the board...

[R_J]

Re: How to test ac transformer secondary output?

Looks like the Blue wire is the center tap and the Red and Brown feed the diodes.
The Black feeds a diode for a negative voltage so it is likely that either Green or Purple goes to ground and the other feeds another diode somewhere?

What is it you are trying to do? just check if the transformer is working?

[JimBanville]

Re: How to test ac transformer secondary output?

Looks like the Blue wire is the center tap and the Red and Brown feed the diodes.
The Black feeds a diode for a negative voltage so it is likely that either Green or Purple goes to ground and the other feeds another diode somewhere?

What is it you are trying to do? just check if the transformer is working?

Yes...the CD player won't power on. Power switch works and I have 120v ac at the output of the power switch pcb. I figured checking the output of the transformer was the next logical step.
My main concern is damaging something by testing voltages between any of these 6 wires. Is that a concern? Thanks for the help

[JimBanville]

Re: How to test ac transformer secondary output?

Looks like the Blue wire is the center tap and the Red and Brown feed the diodes.
The Black feeds a diode for a negative voltage so it is likely that either Green or Purple goes to ground and the other feeds another diode somewhere?

What is it you are trying to do? just check if the transformer is working?

Here's the service manual ...

[R_J]

Re: How to test ac transformer secondary output?

How many threads do you have for this unit? stick to one thread.

[JimBanville]

Re: How to test ac transformer secondary output?

How many threads do you have for this unit? stick to one thread.

Sorry, but I wasn't getting any useful help in the other thread. I'll delete that one.

[R_J]

Re: How to test ac transformer secondary output?

Sorry, but I wasn't getting any useful help in the other thread. I'll delete that one.

If what I provided was not helpful I will stop helping

[JimBanville]

Re: How to test ac transformer secondary output?

If what I provided was not helpful I will stop helping

Sorry. No disrespect intended, but I was getting such general/vague info. I'm competent enough to follow direct instructions, like "place dmm - lead at this point and dmm + lead at this point", but just telling me to check voltages leaves to much room for error. I deeply appreciate any help I can get!! Seriously.