4-Plex Receptacle Design
The Hubbell 4-Plex receptacle is square, and each of the four outlets is placed on one of the corners. It has a built-on cover plate you can affix to a single-gang or double-gang electrical box, and the plate has a knockout plug so you can attach it to a concrete octagon ring or box. All four receptacles are internally connected to a single pair of terminals -- one hot and one neutral -- and all four also are attached to a single ground terminal. The receptacle comes in standard models, rated for 15 amps of current, and hospital grade, which is rated for 15 and 20 amps.
Even though there typically are many outlets in a given room, one often gets used more heavily than the others, and replacing the duplex receptacle at that outlet with a 4-Plex avoids two potentially hazardous situations. One is overloading the receptacle with adapters and plugs, and the other is stretching extension cords across the floor where people can trip on them. Hubbell 4-Plex outlets are useful in high-demand locations such as hospitals and offices, and one model comes with a built-in surge suppressor. Installing one requires no extra electrical rough-in; you can use the existing electrical box.
Connecting the 4-Plex
The 4-Plex outlet is designed to connect to a single pair of circuit wires, and like many standard duplex outlets, it has two connection methods. One is a pair of self-anchoring holes into which you can insert the circuit wires, and the other is a pair of pan-head screws around which you wrap the wires before tightening the screws. Unlike most standard U.S. outlets, the screws on the 4-Plex have Robertson heads, and you need a No.2 Robertson screwdriver to tighten them. The ground terminal also has a Robertson screw. You wrap the ground wires around it, and tighten the screw to ground the circuit.
Installing a 4-Plex
The shape of the 4-Plex receptacle is different from that of standard ones, but you can attach it to any type of electrical box with the proper adapter plate. The plates, which are supplied by the company, have screw holes that allow you to attach them to single- and double-gang rectangular boxes, octagonal and circular boxes, and concrete octagon rings. Once the adapter is in place, you wire the receptacle and connect it to the adapter, much in the same way you wire a light fixture to a ceiling- or wall-mount adapter.