Toroidal CNC Power Supply/ Questions on Wiring

[Sierevello1]

Hello,

I bought 2- power supplies that were supposed to be 68vdc and 12 amps. I just tested one of them and got 34 volts dc at the output. These are supposed to be older Antec units but there are no markings anywhere on them. There are 4 wires coming out of the toroid. There is a yellow/white that comes out of the toroid in the same location and a blue/orange that comes out of the toroid in the same spot. The input is a black and gray wire.

The orange/white goes to one bridge rectifier and then to a capacitor. The blue orange does the same and then they are joined at the output terminal strip. When measuring the the output I get 34vdc and not the advertised 68vdc.

So I am trying to troubleshoot and don't have a whole lot of knowledge on transformers. I assumed 2 things:

1) This should have a primary voltage of 240vac and not 120vac OR
2) It is wired in parallel and not series so I am getting half the voltage.

Anyone have any advice on how to figure this out. I have included pictures.

Thank You,
Steve

[dazp1976]

Hello,

I bought 2- power supplies that were supposed to be 68vdc and 12 amps. I just tested one of them and got 34 volts dc at the output. These are supposed to be older Antec units but there are no markings anywhere on them. There are 4 wires coming out of the toroid. There is a yellow/white that comes out of the toroid in the same location and a blue/orange that comes out of the toroid in the same spot. The input is a black and gray wire.

The orange/white goes to one bridge rectifier and then to a capacitor. The blue orange does the same and then they are joined at the output terminal strip. When measuring the the output I get 34vdc and not the advertised 68vdc.

So I am trying to troubleshoot and don't have a whole lot of knowledge on transformers. I assumed 2 things:

1) This should have a primary voltage of 240vac and not 120vac OR
2) It is wired in parallel and not series so I am getting half the voltage.

Anyone have any advice on how to figure this out. I have included pictures.

Thank You,
Steve

That will be one of those number 2's.

Both input and output will have a series option.
34+34 series = 68
120+120 series = 240

Both will either be parallel or single atm.
You need to find the datasheet for it to make wiring easier to figure out

Image is not there.

[Sierevello1]

Sorry,

It looked like pics were there when I posted. I will have to post them separately I think.

- - - Updated - - -

Next Picture:

[Sierevello1]

There is only a single input: It is a black and gray wire.

[joeavaerage]

Hi,
looking at your picture you have two output windings, the Orange/White winding and the Blue/Yellow winding. The two rectifiers and filter capacitors are in parallel to the output terminals in the centre.
You need to rewire them so that they are in series.


I would not fiddle with the primary, if you wire them in series opposing you will have trouble, whereas series inline no trouble, ie you need to know the phasing of the windings. Easy to do, just
not easy to explain. At this stage I would guess that you don't need to touch it anyway.

Craig