# my transformer has 4 outputs 2 inputs?

Discussion in 'General Electronics Chat' started by DigitalApocalypse, Apr 29, 2013.

1. ### DigitalApocalypse Thread Starter New Member

Apr 29, 2013
2
0
hi all. This is my first time posting. I have aquired a transformer with 4 outputs and 2 inputs. I dont understand, i thought they were supposed to have only 2 outputs (pos and neg) thanks for help in advance.

2. ### tracecom AAC Fanatic!

Apr 16, 2010
3,878
1,396
Transformers have a primary (input) winding and one or more secondary (output) windings. Each winding usually requires two wires. Your transformer apparently has two secondary windings, which may be for two different voltages. It should be marked on the transfomer somewhere; if not, look for a datasheet for the transformer.

Oh, and because transformers are only for AC (alternating current,) there are no positive and negative wires.

3. ### crutschow Expert

Mar 14, 2008
13,475
3,362
The outputs could be either two separate output windings or one winding with taps for different voltages. You can determine that by measuring the resistance between all the wires. If they all have continuity with each other then it is a tapped winding. If there is continuity with only one other wire, then it has two isolated secondaries.

Windings don't have polarity but they do have phase. Thus, depending upon how they are connected, two separate outputs could be in-phase or 180 degrees out-of-phase. That's important in case you want to connect two output in series to get more voltage or in parallel to get more current.

PackratKing likes this.
4. ### BillB3857 Senior Member

Feb 28, 2009
2,402
348
There are transformers that have two primary windings. These are designed for dual voltage input. The low voltage mode is with the two primary windings in parallel, and if they are in series, it is for high voltage. These transformers may also have multiple secondary windings.

5. ### ErnieM AAC Fanatic!

Apr 24, 2011
7,435
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Just do yourself one huge favor and do NOT connect this transformer to the AC line unless you are 100 percent sure of the connections.

Failure to heed this may result in an analog apocalypse.

6. ### BMorse AAC Fanatic!

Sep 26, 2009
2,675
234
most Geiger counters use high voltage to activate the Geiger Tube, in most configurations they will use the 2 secondary windings as power inputs and use the primary windings to power the tube, basically using it to step up the voltage, as in this diagram >>> http://kripton2035.free.fr/Resources/drsb.gif

7. ### DigitalApocalypse Thread Starter New Member

Apr 29, 2013
2
0
thanks. Is how can i find out which are connected to which coils?

8. ### tracecom AAC Fanatic!

Apr 16, 2010
3,878
1,396
Look at the transformer for model numbers, and Google for a datasheet. The datasheet should tell you all about the transformer.

Post some clear, close-up pictures; chances are there is someone here who will recognize the transformer and can tell you about it.

9. ### BMorse AAC Fanatic!

Sep 26, 2009
2,675
234
Or post a few pictures of the top side and bottom side of the PCB. Pictures really do wonders on this forum when it comes down to trying to troubleshoot your issues. A model number of the Geiger counter would also help in trying to google for a schematic diagram