Transformer which is primary/secondary???

[stompvulture]

Need a little help. First time populating a transformer onto a PCB and I have a a 42TM022 transformer for my Tyco Octavia project. Is there a designated side that is primary and secondary, or does it matter? THanks

[Sanguinicus]

It does matter. You've got a model number, try to find a data sheet for it. Isn't there anything labelled on it?

[milosch]

http://www.mouser.com/catalog/specsheets/XC-600134.pdf

You could try to verify with an ohmmeter which pins are the primary, etc.

[familyortiz]

As shown on the mouser datasheet from the previous post, there is a "P" printed on the primary side. You won't miss it.
One other thing, when I got 3 samples from mouser of the 42TM018-RC for my noise free splitter project, 2 of the 3 showed some measureable resistance from primary to secondary. That should not be the case and they should be completely isolated from each other. Good luck.

[stompvulture]

Thanks all for the responses. I'll give it another once over and take some ohm readings to 2X check.

Cheers.