[ARC5] UPS Transformers

[Brian]

Hello Rich,

Good question. To run an American transformer designed for 60 Hz in a 50 Hz 
country, the primary needs to be run at no more than 5/6 rated Voltage. (As 
an aside, perhaps that's why American transformers work so well on Japanese 
100 Vac 50 Hz mains? I wonder whether MacArthur knew that.)

I am well aware that the amount of iron required in the core depends on the 
Voltage, frequency and the type of iron. For my sins, I was production 
manager in a transformer manufacturing firm - so, I knew very well what the 
designers wanted. Luckily, our accountant was all lightning but no thunder.

Since the alleged homologation of mains Voltages in UK and Australia to 
match European standards - so the Europeans can dump their junk on us - I 
have been warning people to look very carefully at the rated Voltage of 
transformers in European white goods. A transformer designed for 220 Vac + 
or - 10% is not happy running at 265 Vac, the kind of peak we get in this 
so-called homologated country. It is cheaper for the electricity 
distribution authorities to run higher Voltage than install new generation 
equipment.

73 de Brian, VK2GCE.

On Thursday, November 19, 2015 1:59 PM , Rich said:

<snip>
Brian, could you possibly be running US-made transformers at 50 Hz in Oz?

Rich KB8TAD