Using a Delta/Wye Trafo in Delta/Delta as well

[edison123]

I am planning on using a 415 V Delta / 6.6 KV Wye, 500 KVA trafo in 415 V / 3.8 KV Delta as well, by bringing out all the HV six terminals and using proper connectors. The application is for no-load test running of MV motors in my repair shop and so the current will be mostly lagging @ 0.2 to 0.3 pf.

Does anyone see any problems with this Delta/Delta reconnection of the trafo ?

 

[Marmite]

What protection is installed? Bearing in mind you are testing repaired motors there is a chance that one could be faulty.

Regards
Marmite

 

[edison123]

These motor windings undergo rigorous HV tests during rewind before they are assembled and test-run. I still plan to use ABB/Areva NC protection covering OL, Earth Fault and Differential on the HV end. Only, we will be using a breaker on the LV side and not on HV. The input voltage will be applied steplessly by a variac.