[Amps] current in primary of microwave oven transformer

[Angel Vilaseca]

Hi,

I have a microwave oven transformer that I plan to use for my next HV 
power supply.

With the secondary unloaded and 220 V into the primary, I measured  670 
mA through it.

This is a 220 V unit so that means 147 Watts, with no load on the 
secondary. Magnetic shunts were taken off.

I have another two MOTs. Made the same measurement. They all behave the 
same.

On the other hand, the transformers do not hum, not smoke, not even get 
hot, so I was wondering if this primary current could be "wattless" 
current, that is a current that is out of phase with voltage.


Should I worry about this amount of "idle current"?

Is this behavior particular to microwave oven transformers?

Is there a way to know what is happening here without using a double 
trace oscilloscope?


Vy 73

Angel Vilaseca HB9SLV