Pad mount Transformers with max 5X inrush current at startup

[drain100]

Looking for some input on inrush mitigation.
I have a project that I am working up and the specification calls for a MAX 5X inrush current on startup.
(5) Transformers for this part of the project.
3750KVA 13.2kv to 4160v
3000KVA 13.2kv to 4160v
1000KVA 480v to 13.2kv
500KVA 4160v to 480/277
225KVA 13.2kv to 480v

customer is requesting pad mount unit.

looking for any input on how to mitigate the inrush somehow or does anyone know of a Transformer MFG that can meet this spec?

any help would be greatly appreciated.

 

[Elect117]

Inrush would be a OCPD issue. I have never been asked for evaluate the effects on a transformer since it is unlikely to be an issue. I would reach out to an engineer to evaluate. More information than just transformer KVA and voltage would be needed.

https://www.eaton.com/content/dam/eaton/products/low-voltage-power-distribution-controls-systems/transformer/files/dtdt-inrush-white-paper-wp009002en.pdf

The above is helpful in showing the contributions to inrush. You would need to have the transformer specifications to properly model it. Mainly the reactance but the resistance also plays a role. Just a impedance percentage (Z%) might not be enough.

 

[ron]

XFMR manufacturers can provide special order units that have low inrush characteristics on the primary at 5x