IEC Power Transformer Ratings
IEC Power Transformer Ratings
(OP)
HI all, I have a 7/8.75MVA power transformer rating. Is this an IEC MVA rating?
My calculated maximum demand load for a 34.5-4.16kV stepdown transformer is 10.294MVA. May I know what OA/FA IEC transformer rating would fit my purpose?
I have no access to IEC rated transformers. Thanks.
My calculated maximum demand load for a 34.5-4.16kV stepdown transformer is 10.294MVA. May I know what OA/FA IEC transformer rating would fit my purpose?
I have no access to IEC rated transformers. Thanks.






RE: IEC Power Transformer Ratings
The ISO 3 preferred numbers are in turn based on Renard numbers (e.g. see http://www.sizes.com/numbers/preferred_numbers.htm). So for your first question, 7000kVA is not a preferred number (however 6300 and 8000kVA are).
For your second question, IEC 60076-1 doesn't say anything about preferred ratings over 10MVA, so you can choose whatever rating you like. Realistically, you should probably check with your trafo manufacturer.
RE: IEC Power Transformer Ratings