240/120V Service

[quantum]

The service is 240/120V. There will be a distribution panel mounted right next to the fused service disconnect. Is the distribution panel required to have a main breaker or will the fused disconnect sitting next to it suffice? The actual installation will have a main, but I my mind got to wondering.....

 

[infinity]

No main required for the distribution panel.

 

[quantum]

Are there limitations? Distance apart? I'd like to read more into why this is permissible.

 

[infinity]

No limit if they're both within the same structure.

 

[kwired]

Keep in mind your panel will need overcurrent protection at or below it's rating.

So if you had 200 amp service overcurrent device:

you could feed a 200 or more rated main lug panel (in same structure) with no additional overcurrent protection

you would need additional overcurrent protection for a less then 200 am rated panel - which could be a main breaker within the panel or a device ahead of the panel.

 

[quantum]

What if the installation is not inside a structure? I.E. a temporary service and power rack located outside with the service disconnect and main lug panel mounted on the rack.

 

[kwired]

What if the installation is not inside a structure? I.E. a temporary service and power rack located outside with the service disconnect and main lug panel mounted on the rack.

In or on same structure is primarily the same thing per NEC.

The line between same or separate structures can get blurred sometimes with things like bulk tanks, bins, etc. and associated conveying and/or processing machines, especially if they are not indoors.

 

[tsparks1]

No limit but your panel must have separate ground and neutral bars as it is no longer the first panel in the structure


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[Smart $]

...separate structures can get blurred sometimes with things like bulk tanks, bins, etc. and associated conveying and/or processing machines, especially if they are not indoors.

Experience from NE Nebraska talking there... :happyyes:

 

[Smart $]

No limit but your panel must have separate ground and neutral bars as it is no longer the first panel in the structure

That's actually based on different criteria. For example, the first disconnecting means at a separate structure would be required to have separate grounded and grounding buses if not supplied by a service.

An SDS could go either way at the first disconnecting means whether in the same structure or not.