DC wiring in conduit, and UL 1741

Photowhit
Photowhit Solar Expert Posts: 6,014 ✭✭✭✭✭
in PV Installers Forum - NEC, Wiring, Installation #1
So I was over at the Midnite forum and informed that all DC wiring needed to be in conduit to meet NEC code...

It appears that Missouri may become more interested in code compliance in off grid systems next year. So I was looking into meeting NEC code for the system I'm setting up. While moving my backup Prosine inverter to my new place I noticed it has UL 1741 cert, which is what I thought was the threshold for home instalation?

Attachment not found.

I know of no battery cable cover for this inverter, it is designed for hardwiring and I know that these are primarily installed in boats and ambulances so did things change? Did this change with the accessable 30 volt thing requiring limited access for ground mounted solar arrays?

I suspect Robin would know since he has been designing inverters for so long but he posted that it has always been required...

Curious minds want to know...

I'll need a slightly larger inverter and likely I'll buy a Magnum next year, but I'll set this up until then. So mostly just curious...
Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
- Assorted other systems, pieces and to many panels in the closet to not do more projects.
· Share on Twitter

Comments

  • jaggedben
    jaggedben Solar Expert Posts: 230 ✭✭
    #2
    Re: DC wiring in conduit, and UL 1741

    The 'threshold' is that the NEC requires that equipment be listed by a Nationally Recognized Testing Laboratory. Being listing to UL's 1741 standard accomplishes that for the inverter. But all this means is that an inspector can't say to you "You fail this inspection for not using a listed inverter." UL 1741 is mostly about inverter operation and has little or no bearing on whether the manufacturer also designed the inverter so that the installation can easily comply with the rest of the NEC. As far as meeting NEC code with respect to batteries, look at 690.71. Battery cables are covered by Chapter 3 or article 400. You may need to fashion a cover for the battery terminals, or put the inverter inside a cabinet that can be latched shut.
    · Share on Twitter

Categories