• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Transformer hook-up question to 115V AC line

This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Joined 2003
I see that a number of people have looked at your post without replying, and I guess that they hesitated for the same reason that I did. You really need to learn some more about electricity and electronics before you connect things to the mains, otherwise there is a very serious danger that you will kill yourself and/or start a fire.

To answer your question, most mains transformers intended to be able to connect to any mains voltage have two windings. You need to connect the two 0V together and take them to the "N" terminal on the IEC, and connect the two 120V together and take them to the "L" terminal on the IEC. Unless your transformer is exactly as I have suggested, do not do anything. It's very easy to start a fire.

I trust that your IEC socket is of the type with an integral fuse? Finally, you need to take a nice fat wire from the "E" terminal, solder it to a solder tag, and screw that solder tag as firmly as possible to the chassis with a shakeproof washer between the tag and the chassis.

But more importantly than all that, please spend a day at the library and read some fundamental electronics books to find out about what is going on. Electricity can kill you, and if it does, it will do so in a particularly nasty way.
could the 130 be a badly written 230?
the other numbers are clear.
and there is a wire connecting the left 120 to the 0, on the bottom.
I do not find an E terminal on either side.

the other side has a top row of terminals, nothing on bottom:

other side top row:
two pins marked, 6:3. and two pins marked: 13.6V.

I was hoping to use the 13.6V to supply this solid state psu: http://www.welbornelabs.com/ps1.htm, but I don't know whether the 13.6V is AC or DC and I don't know how many amps (there are no markings). I wanted to correctly hook up the other side to 115V AC via IEC plug, and use a volt-meter to test the 13.6V. I would leave the other pins with nothing connected.

the transformer is Audio Note TRANS-010.
it seems the markings 6 : 3 is to be used with 'valve 472A', and 13.6V with '5684', which are written below these markings. Maybe this could tell someone more knowledgable if this 13.6V is AC or DC, and I would have to hook this up at all.
Joined 2003
It's the lack of a second 0V that surprises me. In theory, you could wind a transformer so that it could be used simply by applying 110V between the 0V and 110V taps, but it would require thicker wire for that section of primary and would be a very wasteful solution.
I am no expert, but maybe your trafo is winded like the picture I attached. This configuration could be used for multiple mains voltage, read carefully COULD BE (holding some disadvantages against double primary winding) and is surely very strange.

But assuming the picture is right...You sure have a multimeter...measure the impedance between the different pins. Impedance between the 130 at the top and 120 at the bottom should be high (well, high is less than 10ohm, probably), impedance between top 120 and 0 and 0 and bottom 120 should be the same...impedance between 130 and 120, 120 and 110 (all at the top) should be very low. I think it's best to use a analog multimeter for this.


good luck


  • trafo.jpg
    8.1 KB · Views: 108
If you measure continuity between any of the high voltage pins and any of the low voltage pins, do yourself a favor and get another transformer, as this would be an autotransformer (single piece of wire, can put mains current onto chassis if not connected properly :dead: )
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.