by Nasadowsk
/*the M2 was built for 11500 volt only and at 60 Hz can take 12 500 as the core saturate sooner with higher frequency.
*/
That's nice. Backwards, but nice.
As the frequency drops, the saturation voltage does too. That's why a 25hz transformer needs to be so much bigger than a 60hz one for a given voltage. The upper limit of the permissable flux is a function of the transformer's construction, the amount of iron, etc. It's fixed for a given transformer. The flux is a function of the input voltage, i.e. it's the integral of the sine wave. Lower frequency = more flux for X voltage. You either drop the voltage or raise the frequency. Thus, for a given transformer, the input voltage goes up with frequency, though this is within limits because at some point the transformer stops working for other reasons.
At X voltage, a transformer that runs at 25hz can generally work at 60hz, but at X voltage, a transformer that runs on 60hz will NOT run on 25hz.
Anyway, the big red book on the M-2 will have the transformer's name plate and photos of it in there, with ratings. The tap switch will be internal to the tranny, BTW - there's only a HV bushing and a ground bushing on the LV side.
You don't want the core to saturate. Bad things happen when it does.
*/
That's nice. Backwards, but nice.
As the frequency drops, the saturation voltage does too. That's why a 25hz transformer needs to be so much bigger than a 60hz one for a given voltage. The upper limit of the permissable flux is a function of the transformer's construction, the amount of iron, etc. It's fixed for a given transformer. The flux is a function of the input voltage, i.e. it's the integral of the sine wave. Lower frequency = more flux for X voltage. You either drop the voltage or raise the frequency. Thus, for a given transformer, the input voltage goes up with frequency, though this is within limits because at some point the transformer stops working for other reasons.
At X voltage, a transformer that runs at 25hz can generally work at 60hz, but at X voltage, a transformer that runs on 60hz will NOT run on 25hz.
Anyway, the big red book on the M-2 will have the transformer's name plate and photos of it in there, with ratings. The tap switch will be internal to the tranny, BTW - there's only a HV bushing and a ground bushing on the LV side.
You don't want the core to saturate. Bad things happen when it does.