CB AIC ratings - clear terminology?

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tx2step

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North Texas, DFW area
I'm having to write a short requirement for adding a 200/3 and 400/3 CB into an existing 480/277V 1200A 3ph MLO panel (MDP). The service entrance from the padmount utility transformer to MDP is maybe 12' to 18' long, lug-to-lug. This will be CB's #4 and #5 in the panel, so it's still under the maximum # of 6. I want to make sure they select the correct AIC rating for the new CB's, without telling them what they should use (they're getting paid to do it). I'll be inspecting the installation, but they will be doing & are responsible for the design (not me). The installation will be done under the 2002 code. Is the following clear enough (or does it need refinement)?

"Provide documentation of the Available Short-Circuit Current at panel MDP, and the Interrupting Rating of each new circuit breaker to be added to panel MDP. Ensure circuit breaker short-circuit interrupting ratings exceed the available short-circuit current. Comply with 110.9 and 110.10."
 
tx2step said:
I'm having to write a short requirement for adding a 200/3 and 400/3 CB into an existing 480/277V 1200A 3ph MLO panel (MDP). The service entrance from the padmount utility transformer to MDP is maybe 12' to 18' long, lug-to-lug. This will be CB's #4 and #5 in the panel, so it's still under the maximum # of 6. I want to make sure they select the correct AIC rating for the new CB's, without telling them what they should use (they're getting paid to do it). I'll be inspecting the installation, but they will be doing & are responsible for the design (not me). The installation will be done under the 2002 code. Is the following clear enough (or does it need refinement)?

"Provide documentation of the Available Short-Circuit Current at panel MDP, and the Interrupting Rating of each new circuit breaker to be added to panel MDP. Ensure circuit breaker short-circuit interrupting ratings exceed the available short-circuit current. Comply with 110.9 and 110.10."
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That's very clear and simple to me, although I might add "...and that the new circuit breakers are properly UL listed for use in panel MDP."
 
and have them report to you the short circuit rating of the panelboard interior itself and the AIC rating of the existing breakers in case they are under rated. Once you touch it, there is an implied acceptance of the existing conditions.
 
Also note that if adding more load should end up triggering a change of transformer capacity - whatever is existing (both the panel bus and existing breakers and possibly downstream components as well) will need re-evaluated to see if it is suitable.
 
I've tried to draft some generic requirements for when I run into situations similar to this in the future. Is the following clear enough, or does it need additional refinement?

"Provide documentation of the Available Short-Circuit Current at existing panel [MDP], and the Interrupting Rating of each new circuit breaker to be added to panel [MDP]. Ensure circuit breaker short-circuit interrupting ratings exceed the available short-circuit current, and that the new circuit breakers are properly listed for use in panel [MDP]. Comply with NEC 110.9 and 110.10.

Provide Short-Circuit Current rating of existing panel [MDP], as well as the Short-Circuit interrupting ratings of each of the existing circuit breakers in panel [MDP].

Provide load calculations for panel [MDP]. Provide rated amp capacity of existing panel [MDP], as well as the rated amp capacity of the conductors supplying service power to existing panel [MDP] for each phase and for the grounded (Neutral) conductor."

Any suggestions?

Thanks!!!
 
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