Understanding 706.30(A)

[philly]

I'm looking at 706.30(A) for an ESS which consists of a battery storage system which connects to a DC/DC converter as part of a charging system. In looking at this system I'm trying to determine the circuit sizing and current per 706.30(A) to then determine overcurrent protection size per 706.30(B).

From 706.30(A) i'm trying to determine which what determines the size of the system for sizing feeder between battery and DC converter. The battery system has a nameplate listing of 760A while the converter has an input nameplate of 500A. The two choices in this code section that seem to be applicable here are (1) and (5). Would the battery rating be what is stated in item (1) of section? If so would you use the larger of these two to determine system size or use the lesser of the two (converter in this case) which will dictate load.

I would think that with the converter dictating loading from batteries this would be considered for definition of ESS size per 706.30(A)?

Am I understanding this correctly?

 

[tortuga]

I'm looking at 706.30(A) for an ESS which consists of a battery storage system which connects to a DC/DC converter as part of a charging system.

Is it actually a listed ESS? I think of 706 as only applying if I get a prepackaged Energy Storage appliance that has a nameplate.
Then I'd go off that nameplate to connect to the AC system.

If its not a listed ESS its a battery and a DC/DC converter, the battery would fall under article 480.

The battery system has a nameplate listing of 760A while the converter has an input nameplate of 500A.

Is the DC/DC converter bidirectional?
Or is it only ever a load ?
I would think you would protect the weakest link the DC/DC converter,
Its interesting how we have an article on transformers and one on phase converters but nothing on plain DC-DC converters.