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Problems with power transformer...need help!

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Praxis:
I recently acquired this transformer from Jameco: https://www.jameco.com/Jameco/Products/ProdDS/104417.pdf

Now, this is the first time I've ever used a transformer with multiple primaries.  I thought I had it wired correctly -- neutral to the middle two tabs and hot to the outer two tabs on the primary side, but when that's plugged in (with no load -- nothing's connected to the secondary taps) the thing passes tons of current -- it blew a 5A fuse in under a second -- not to mention heating up to the point where you get that hot-electronics, immanent-thermal-destruction smell.  So now I'm not too sure I'm reading that data sheet correctly.  Any help would be appreciated, thanks.

Zero999:
It's blown the fuse because you've just short circuited the primary.

The schematic on the datasheet appears to be incorrect. Try measuring the resistance between 2 & 3, I'm guessing it should be open circuit.

If that's true, for 120V operation, 1 & 3 should both be connected neutral and 2 & 4 should be connected to 120VAC.

ciccio:
Hi praxis,
I think that you are reading the data sheet correctly, but the data sheet is wrong:
It is not possible that a transformer primary is wired as the data sheet's drawing.
If you had such an high current, the primary was short-circuited.

A dual-primary transformer has two separate winding, in your case they should be:
pin 1 : 0 V - pin 2: 115 V
pin 3 : 0 V - pin 4: 115 V
(this will require this wiring: neutral to pins 1+3, phase to pins 2+4)

or, in alternative, that will may result in a simpler wiring (and is the wiring standard from my favorite supplier)
pin 1 : 0 V - pin 3: 115 V
pin 2 : 0 V - pin 4: 115 V
(this will require this wiring: neutral to pins 1+2, phase to pins 3+4)

or, last possibility (really stupid)
pin 1 : 0 V - pin 4: 115 V
pin 2 : 0 V - pin 3: 115 V
(this will require this wiring: neutral to pins 1+2, phase to pins 3+4) : this is how you wired at your first attempt, so I will exclude this possibility).

Please check if there is continuity between all the pins: there should be two insulated windings.

After this, if the transformer is still alive after your previous test, and you have access to a function generator or an audio oscillator and a scope, test the different wirings by  the primary with the oscillator, set at 60 Hz, 10 V rms, and check the secondary with the scope. Only one of the above wirings will give you some secondary waveform: all the others will result in out of phase primaries, with no secondary output.

Good luck...

Praxis:
Arrrgh.  I -thought- the diagram of the winding was a little weird, but to be honest, transformers are black boxes to me at this point and I don't really know enough to assume right off that the datasheet was wrong.

I think it's still alive.  I don't have an AF oscillator, but how about hooking it into a (verified working) 13-ish volt transformer's output?

Zero999:
Connecting it to 13V is a good way of testing it. If it's connected correctly, you should get around 4V on the secondary.

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