Commercial Retail Store Calc

[rgiraldo]

just want to check to see if I am correct.

Continuous Loads
4000 sqft @ 3va per ft 12000va
Show Window- 30ft @ 200va per ft 6000va
Sign 1200va

19200va X 1.25 = 24000va

Non-continuous Loads

76 receptacles @ 180va 13680va
First 10000va @ 100% 10000va
Remain 13680-10000=3680x50% 1840va

11840va

Air conditioner #1 6900va
Air conditioner #2 6900va
Cylinder Machine #1 1500va
Cylinder Machine #2 1500va
Compressor + 25% 2500va
Water Heater 3000va


Total Volt Amps 58140/240=242.25a

Panel @ 400a
Breaker @350a

Where can I cut the fat to keep it under 300A total?????

Please let me know if I missed a step or missed a reduction some where

:?

 

[david luchini]

Total Volt Amps 58140/240=242.25a

Panel @ 400a
Breaker @350a

Where can I cut the fat to keep it under 300A total?????

Please let me know if I missed a step or missed a reduction some where

:?

Not sure I understand the question. You can put this a 250A MCB panel with a 250mcm (cu) feeder.

 

[rgiraldo]

I thought the breaker needed to be upsize 25% for continuous loads. Or did I all ready do that with my general lighting.?

 

[rgiraldo]

My understanding is that panel bus bar must equal load amp and main panel breaker x 1.25%.

 

[david luchini]

I thought the breaker needed to be upsize 25% for continuous loads. Or did I all ready do that with my general lighting.?

You already did that. Your breaker needs to be larger than 100% of your non-continuous loads plus 125% of your continuous loads. (See 215.3.)

As your calc shows, that's 242.25A, so a 250A c/b meets the requirement in 215.3.

My understanding is that panel bus bar must equal load amp and main panel breaker x 1.25%.

Your panel bus bars must be protected with OCPD greater than or equal to the bus bar ratings. (See 408.36.)

This can be a 250A MCB with 250A rated bus bars, or it could be a 250A MCB with 400A rated bus bars, etc. There is no requirement for the bus bars to be larger than the OCPD protecting the panel.

 

[rgiraldo]

Great news, I appreciate your help

 

[david luchini]

Great news, I appreciate your help

You're quite welcome. Of course, using a 250A panel won't afford you very much room to add any additional load, with your current loads, if that is a concern.