120/240V Connected Phase Amps vs. Panel Amp Rating

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necnotevenclose

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I'm working on a commerical project that has an existing 120/240V, 1-phase service. The owner would like to add loads to an existing 200A MLO panel. When I input the loads the connected phase amps they are in excess of the panel rating (say 230A). However the demand amps are below 200A.

Since the connected phase amps is greater than the panel bus rating does this mean the panel should be upsized to a larger panel rating?
 
Not necessarily (contrary to iwire Bob's reply).

If by "connected phase amps" you mean summed load VA exceeds 48kVA (200A ? 240V), but after applying demand factors and factoring for 125% continuous plus non-continuous you have less than 48kVA... conditionally no. The condition is imbalance of loads vs. how much below 48kVA. A non-technical evaluation is, if the imbalance exceeds the 2x the difference... yes.
 
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The connected load can exceed the main breaker rating. If the actual load exceeds the main breaker rating, the main breaker will trip. The main breaker is intended to protect the panel bus from overloading. Though you say it is an MLO panel, there has to be a breaker on the feeder to it.
 
This may just be semantics...
When I read the OP I tend to agree with beanland. If "connected" load consists or equipment connected to the panel or ampere rating of the breakers, this number will often exceed the panel buss/feeder rating as long as diversity keeps the rating below the panel main.
 
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