What is the minimum box volume required for a L5-30R receptacle? This is a 125V, 30A, single phase twist-lock receptacle. Is a 4" box required or is a 2" single gang box acceptable. Also are there any special mounting requirements due to the twisting action required. Can the box be tabbed directly to the drywall opening with no attachment to wall framing (for after the fact installation). Thanks in advance.
Christopher Banbury, PE President Ark Engineering, Inc. PO Box 10129, Brooksville, FL 34603 22 N. Broad ST, Brooksville, FL 34601 Phone: (352) 754-2424 FAX: (352) 754-2412 www.arkengineering.net
The manufacturer may have instructions but the NEC is silent on the mounting. Box fill is 2 conductors allowance, same as any device. That doesn't mean it will fit. Common sense says use a box that has enough room and mount this securely. Twist lock implies there will be some extra strain on the cord and you won't simply pull out the plug cap. We used a lot of twist lock and usually put them in a 4" box with 4 screws per device.
Iwould use a deep 1Gbox to allow the wires some room.
If you are worried about the twisting working the old work box loose after awhile look at using one of the new smart box style old works that screw to the side of the stud.
