Transformer ringing sounds

[dwightCollins]

When you hear a transformer ringing sound or sounds from a transformer how do you know if it's from overloading the secondary or overdriving the primary? or what else can it be?

When overloading a transformer it makes rings sounds
When overdriving the input it makes ringing sounds

What test can i do with the O-scope to know if the transformer is overdriven or overloaded?

What else would cause ringing in transformers?

 

[ronsimpson]

what type of transformer? Power 60hz, audio, switching 100khz?

 

[dwightCollins]

AC 60hz and AC 400hz , how do I know if they are being overloaded or overdriving?

What kind of tests can I do please? using an O-sc0pe

The sounds from the transformer when being overloaded or overdriving are harmonics?

 

[dr pepper]

I dont know if this applies to you totally.

Primary oveloading can occur in 2 main ways, too high a current per mm2 of copper, this can be checked by measuring the current into the primary and measuring the physical size of the copper, core saturation isthe other, this can be checked using a 'scope and a resitor in series with the primary, distorion of the current wave indicates saturation.
Oveloading the secondary on a well designed transformer can usually be found just meassuring the voltage and calculating it back from the transformers regulation parameter, and of course by observing how warm the trans gets.

You can al;so measure he phase difference between the pri and sec, but you need comprehensive data on the transformer to know what to expect.

This is only a rough guide (before someone smokes me).