Isolation transformer setup question

sirgubster9

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Got this transformer. How do I know which two tabs go in and which two tabs go out? And if I do it wrong will bad things happen?
 

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Verify with meter the 2 different coils in the transformer. Should ohm out to the same value; Wire gauge looks the same, so you can use either side for input/output. Only if there were other secondaries on that core would I be concerned.
 
There isn't really an in and an out. There is just two coils wrapped around an iron core. I'm sure there is an optimum one to use as the input but it wont blow up if its wired one way vs the other.
 
To be clear, one of the pairs of terminals that you measure continuity between will be the input, and the other pair (which you should also measure continuity between) will be the output. If it's an isolation transformer, it shouldn't matter which pair you use as the input and output, since the ratio between the two coils is 1:1, meaning the output voltage will be the same as the input. (As opposed to other types of transformers, which can step the voltage up or down).

You should also verify that there is no continuity between the two coils (i.e., verify that they are isolated from each other). And as mentioned above, don't just test continuity, actually measure the resistance of each coil, to make sure they are the same. Never assume an unknown transformer is an iso, unless you actually measure it.

This post by me (and the rest of the thread) explains it further, and has a picture. Make sure you understand how these work if you're going to use one. Google can help more if needed.

 
Ohhhhhh I thought it could only be an isolation transformer, didn't know there where other options. OK very good to know. Ohms. And continuity. Know how to test those. Can do. Thank you.
 
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