Generator Fittings and Spare Parts

Connecting a generator safely: inlet boxes, cords and transfer gear

A power inlet box gives a generator cord a safe entry point to the house wiring. Its amp rating, such as 30 A, and its plug configuration must match the generator's outlet and the cord, and the inlet box must connect to the house through a transfer switch or interlock, never directly to a wall outlet. Plugging a generator into a wall outlet can energize the lines outside, which endangers utility workers, and overload the wiring.

Always run a portable generator outdoors and well away from windows, doors and vents, because its exhaust contains carbon monoxide. A cover protects an idle generator from rain and dust, but it must only go on when the engine and exhaust are completely cool. Covers are listed by the wattage range of the generators they suit, such as 1200 to 1875 W, so match the cover to your generator's frame and size.

Ferrules, silencer inserts and the odd-fit parts

Wire ferrules are small metal sleeves crimped on stranded wire so it seats cleanly in a terminal. Size the ferrule to the wire gauge, for example 14 AWG, and use a ferrule crimper that matches its shape. The color often shows the size, but codes vary between makers, so check the stated gauge. Pack counts such as 250 are common, so check the quantity before comparing.

Exhaust silencer inserts and similar internal parts are sized by length, width and depth, for example 14 x 10 x 9, and are specific to a silencer or generator model; match the part number rather than the shape. Welding accessory kits list cable length, such as 50 feet, and the amp rating of the cable and clamps, which must suit the welder. Always switch off and let hot parts cool before servicing.

Questions about Generator Fittings and Spare Parts

Why can't I plug a generator into a wall outlet?

Doing so can send power back into the utility lines, which is called backfeeding. It endangers line workers, can damage the generator when the grid comes back and can overload household wiring. Use a power inlet box with a transfer switch or interlock installed by a qualified electrician.

How do I choose a generator cover?

Match the cover to your generator's dimensions and wattage class, not just its looks. Check length, width and height, and leave room for the handle and wheels. Covers are for storage only: remove the cover before starting the engine, and fit it only after the generator has cooled.

What do wire ferrule colors mean?

Ferrule colors indicate the wire size they are made for, but the coding differs between makers and between metric and AWG ranges. Use the stated gauge, such as 14 AWG, and the length of the crimp barrel as your guide, and crimp them with a tool made for the style.