[RE-wrenches] Ground Mount PV DC Disconnects and 690.13

[Dave Palumbo]

Wrenches,

 

For a ground mounted PV array I do NOT see where 690.13, 690.14 mandates a
DC disconnect at the array itself. My question is what do you do as "best
practice" for safety, or for service of inverter disconnect. I have been
using 600VDC SQ-D disconnects at our ground mounts and I'm wondering if it's
just plain overkill, or reasonable practice. 

 

 For example: 4kW Ground Mounted PV array with a Maximum Voltage of 567 DC.
DC wire run (buried pvc conduit) of 150 feet to the inverter with integral
DC disconnect. Inverter is located on outside wall of the house next to
utility service.

 

Also. With this system, if I use a DC disco at the array, can I safely use
the SQ-D HU361RB 30 Amp 3 pole 600VDC disconnect. The system is one string
of 20 Evergreen 205's, so 11.93Isc x 1.25 for a current of 14.94 Amps Max.
By using 2 poles in series can we use this disconnect safely?

 

Dave

 

David Palumbo, NABCEP Certified PV Installer

Independent Power LLC

Offices in Lamoille and the Champlain Valley

802.888.7194 

www.independentpowerllc.com 

 

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