Transformer design& Sizing documents

[mehdi1351]

Hello all,
I am currently dealing with Texas POCO (Swepco) to order 2 transformers. What they asked me was only limited to the load list and last week they already ordered the transformers. I am a bit concern on why the transformers got ordered without and sizing/adequacy check criteria checked by myself (as a user of the device).
Is that quite normal in US?
As far as I know, there are 2 adequacy check on the transformers that should be part of the transformer sizing documentation, but seems like the POCO got all the responsibilities in this area, rather than sending the design/calculation document to me for review/approval prior to order the transformers?

Any thoughts?

 

[Eddie702]

If the POCO is supplying the transformers then they are responsible for the sizing

 

[mehdi1351]

If the POCO is supplying the transformers then they are responsible for the sizing

But what if I experience volt drop more than 15% on one of my electrical devices or any overload happens during the starting of the largest motor in the plant, beyond the acceptable limit?
This is quite non-make sense to me!!
They need to provide the sizing calc and all documentation to the service user for approval prior to ordering the transformer. This is normally what we do in Middle east. Seems like US is different

 

[petersonra]

But what if I experience volt drop more than 15% on one of my electrical devices or any overload happens during the starting of the largest motor in the plant, beyond the acceptable limit?
This is quite non-make sense to me!!
They need to provide the sizing calc and all documentation to the service user for approval prior to ordering the transformer. This is normally what we do in Middle east. Seems like US is different

They have a lot of experience at sizing their equipment. And the tariffs require them to provide voltage at certain standards.

It's doubtful you would experience a 15% loss of voltage during a start because the tariffs also prohibit you from starting motors across the line above about 50 hp.