400A gear fused at 200A

[olly]

I work for a POCO, occasionally a customer wants to install a 400A rated main disconnect and install 200A fuses. I can never get a reason why? Future expansion, no. I would think the 400A would be more expensive. We bill based on size of disconnect rating not the fuse size.
Anyone have an Idea why they want to do this?

 

[kwired]

Maybe because of voltage drop they wish to run larger conductors then the 200 amp gear will accommodate or other similar situation?

 

[Carultch]

I work for a POCO, occasionally a customer wants to install a 400A rated main disconnect and install 200A fuses. I can never get a reason why? Future expansion, no. I would think the 400A would be more expensive. We bill based on size of disconnect rating not the fuse size.
Anyone have an Idea why they want to do this?

If there's a significant expense to the change from 200A to 400A, and voltage drop curtailment is the reason (rather than future proofing), recommend that they put in a 200A main disconnect fused at 200A, and splice the load side conductors in a separate enclosure with insulated tap connectors.

 

[kwired]

We bill based on size of disconnect rating not the fuse size.

bill for what?

Most POCO here have construction charges to initially provide service but is based on actual equipment they provide, and may even consider the estimated load and return on investment in energy sales revenues.

I have recently put in 400 amp 480 volt service gear at a grain storage site, but the load could have been handled by 150 amp or less. POCO only provided transformer capacity for the actual connected load which was about 90 Hp of motors expected to run simultaneously at any one time and not the 400 amp capacity of my service disconnecting means. I think they only provided 75KVA transformer bank, maybe 112.5. If customer increases the load someday they will change the transformers and bill accordingly/credit for the old ones.

Same customer had another site that we added more load to this past season, same POCO changed a 300 KVA transformer to a 500 - I never changed any of the service equipment though as it had been sized for future expansion.