I am running both single phase 240 and three phase 240 in my shop. I discovered that each of the locking, industrial round plugs for these (L14-30R and L15-30R) can fit in one double gang box. Is there any code problem with doubling them up? The single phase 240 comes from the breaker, and the three phase 240 comes from a three phase converter fed from the same panel.
Electrical – Any code problem putting single phase 240 and three phase 240 in same outlet box
electrical
Related Solutions
NEMA 14-20 are intended for two phase power. Of the four conductors, two are energized, one is neutral, and one is ground.
(NEMA 14-20 diagram)
A NEMA L15 is specifically intended for 3 phase power including a ground (but no neutral). The number after the hyphen is the current rating. That is, NEMA L15-60 is for 60 ampere conductors.
(NEMA L15-20 diagram)
As you can see, they look vitually identical. See the full chart here.
I can see why one would make the substitution. The NEMA 14 is like a $25 connector. The L15-20 is closer to $60, each side. They both accommodate four wires. I am sure it would not pass muster to substitute one for the other, but in a private, non-commercial, non-permanent installation where there is no possibility of intermixing the connectors with other devices and outlets, it might be okay safety-wise with durable signage present.
Take the incoming hot (black) and wirenut it to black pigtails going to the brass LINE HOT screws on each GFCI. Take the incoming neutral (white) and wirenut it to white pigtails going to the silver LINE NEUTRAL screws on each GFCI. Take all the grounds and wirenut them to each other and to bare pigtails to the green ground screws on each GFCI -- if you're in metal conduit with metal boxes, simply get self-grounding GFCIs instead.
With a single 12-2 and two yokes, you'll be nowhere near box fill for a double gang box, by the way.
Related Topic
- Electrical – Hybrid 1ph/3ph load center fed by rotary phase converter
- Electrical – Chinese Breaker Box (240v split-phase?) Lacks Neutral Wires and Grounding Bus
- Electrical – Is it safe to change an Indian 16A to 250 V round pin plug to a UK 3 pin 13 Amp as used in 220-240 V Kenya
- Electrical – Does commercial wiring differ from residential wiring downstream from the main panel
- Electrical – Getting 120v single phase & 240v three phase out of 240v single phase receptical
- Electrical – Install a 60 AMP Breaker and Outlet with 220 – 240 Volts 63 Amp in My Home
- Electrical – Dryer receptacle on sub-panel feeder
- Electrical – Replacing old plug-in 220V range with new hardwire 3-wire electric cooktop: remove outlet or add a plug
Best Answer
Yeah, the plugs may not physically clear when installed next to each other at 1-gang spacing. I would recommend using 2 separate boxes for that reason.
That said, you can put both voltages in the same junction box, but you must clearly mark them to distinguish them.