ECN Forum Forums General Topics of the Trade General Discussion Area Electrical Design Issues: White Paper

SCSD
Like Electure says, I think we are not sure what you are asking.
I am not familiar with Siemens panelboards, but could look up specifics from a catalog. Need to know your question.
Panelboard mounted on a platform need to have seveal questions addressed. First, is how much working clearance do you have? Accessibility?
With a 225A Main Breaker, the max. limitation will be 225A, except for inrush current of a short duration.
Where is the 300Amps available coming from? An upstream panelboard or switchboard breaker?
Are you expecting 400Amps of continuous power consumption?