ESS DISCONNECTING MEANS label NEC 706.7 (D)

Zee

Senior Member
Location
CA
On a residential PV system - with an ESS - how is the following Code-required label properly worded:

2017 NEC 706.7 (D)

Notification. The disconnecting means shall be legibly marked in the field. The marking shall meet the requirements of 110.21(B) and shall include the following:
(1) Nominal ESS voltage
(2) Maximum available short-circuit current derived from the ESS
(3) The associated clearing time or arc duration based on the available short-circuit current from the ESS and associated overcurrent protective devices if applicable
(4) Date the calculation was performed



I got (1). 450/400 VDC charge/discharge.
I have no idea about 2 and 3.
Is this even applicable?

Equipment is SolarEdge Storedge 7600A-US with LG CHEM RESU10HR
 

jaggedben

Senior Member
Just my opinion:
This code section needs to be changed because it is not necessary or applicable for an ESS which is a listed assembly with a regulated output. My impression is that it is applicable for field assembled battery banks, not units like the RESU10H.

So far I'm just waiting to see if any inspector brings this up.
 
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Zee

Senior Member
Location
CA
I'm gathering that on a DC coupled system, like LG Chem or Generac, all we need is the words...... Energy Storage System Disconnect ......and the maximum DC voltage.
(520 VDC and 420 VDC respectively.)

Sent from my SM-G950U1 using Tapatalk
 

jaggedben

Senior Member
I think you can get the short circuit current from the manufacturer. (3) and (4) I think are not applicable.
 
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