Checking DC Resistance of a Transformer

I was told this machine caught fire about a year ago around the transformer when the whole plant electrical system single phased. They since put in a phase balance detector that will kill the main power to the machine.

I don't see how a 3 phase transformer with a delta primary would go bad or catch fire only from single phasing. All this makes me suspicious that it has the wrong transformer.

I expect to be back at this plant this week and intend to do a little more investigating.

Is this a European machine 400V/50Hz?
Instead of 480Delta to 400Y, I have had much better result with 480D - 380Y transformer.

BachPhi said:

Is this a European machine 400V/50Hz?
Instead of 480Delta to 400Y, I have had much better result with 480D - 380Y transformer.

Click to expand...

Yes, it was built in Austria about 15 years ago. The main reason for the transformer is because the mold heaters were designed for the voltage in Europe.