Bell 5390-0 Three-Gang Electrical Box 55 cu in

Three-Gang Box for Outdoor Wiring

The Bell 5390-0 is a three-gang aluminium electrical box rated for 55 cu in capacity. It carries CSA and UL Listed markings for code-compliant installations. The grey finish suits exterior mounting on walls or poles. Contractors and electricians use it to house multiple switches or receptacles in damp locations.

Upgrade from Smaller Single-Gang Boxes

A 55 cu in three-gang box replaces one or two smaller enclosures when a circuit requires three devices in one location. The jump is worth it when conduit entries, device count or wire-fill calculations exceed the volume of a single-gang body. Consolidating devices reduces the number of wall penetrations and simplifies weatherproof sealing.

Limits of the 55 cu in Volume

The 55 cu in capacity sets a hard ceiling on conductor count and device size under NEC fill rules. Large dimmers, GFCI units or heavy-gauge wire can consume the allowance quickly, leaving no room for additional splices. Installers must calculate fill before adding a fourth device or upsizing conductors beyond what the volume permits.