Transformer Problem

[Noobdude2.0]

I know a transformer is extremely dangerous and I am using extreme caution.

Now that you know I know it's dangerous maybe you can help me out.

I purchased this transformer https://www.mpja.com/prodinfo.asp?number=7845+TR

for a project I want to do but the wires are a little confusing to figure which one is the primary.

I have pictures below of the transformer with the wires

 

[KMoffett]

This transformer is made to work on 120VAC or 240VAC on the primary. To work on 120VAC, the two Black wires are connacted to one side of the power line, and two Red wires are connacted to other side of the power line. The work on 240V the outside Black is connected to one side fo the power line, the center Red and Black are connected together, and the outside Red is connected to the other side of the power line.

Ken

 

[Hero999]

I know a transformer is extremely dangerous and I am using extreme caution.

That's not true, transformers aren't dangerous, not using a transformer is.

 

[peter5355]

Please Please help me have problem telling what is the primary and what is the secondary windings of the transformer.
I read this some where that you can tell with an OHM meter what is the primary and what is the secondary primary will be less than the secondary it is an audio transformer I have.
But before I can get a reading it goes away

 

[dknguyen]

Primary means the input side of the transformer and secondary means the output side. BUT they are completely arbitrary because every transformer works just fine backwards and forwards. THe only difference would be the turns ratio if it was not 1:1.

If the turns between the two sides are unequal, you can figure out which side has more turns by measuring the resistance since the side with more turns has more wire, and thus more resistance. However, in some cases your ohmeter might not be sensitive enough since the resistance can be very low.

THe other way is to use a function generator and send an AC signal through the transformer. By measuring the voltage at both ends, you can figure out which side has more turns or less turns.

BTW you can make your own thread by going to the top right on the forum list of threads and clicking "new Post" rather than posting in someone else's thread.

 

[peter5355]

Transformers

Thank you for your quick reply that is helped a lot you know your stuff