Class A E VTs

[entropically]

We've got some older Asea 33kV VTs sitting in storage that I'm considering installing. They're marked Class A E. Anyone got any ideas on what class this would translate to under the modern BS/IEC standards?


Thanks.

 

[Marmite]

Looking at my old books it looks like the classes are from BS3941: 1965.
Class A is a measurement VT.
At 0.9-1.1 times rated primary voltage, 0.25-1 times rated output at unity pf. Voltage error plus or minus 5%, phase error plus or minus 20 mins.

Class E is measurement/protection VT.
At 0.05-0.9 times rated primary voltage, voltage error 3%, phase error 120 mins.
At 1.1 to (Voltage Factor) times rated primary voltage, voltage error 3%, phase error 120 mins.

Regards
Marmite