Electrical Box Knockout Sizes

Trade size in 1 1 2 57 1 1 4 62 1 2 152 1 93 2 1.

Electrical box knockout sizes.

What are the actual hole saw sizes for the various trade sizes of electrical conduit. 1 2 to 2 152. Hydraulic with piece maker. 1 2 to 4 154.

Knockout type conduit size hole range part number page no. 12 awg is larger than 14 awg so a box can have fewer 12 awg conductors than 14 awg. I know that i will need to drill with hole saws or use a knockout punch in junction boxes and the circuit breaker panel. Different electrical box sizes fit varying installation needs.

Electrical trade sizes and plumbing trade sizes are equal and are based on pipe sizes. Standard household circuits are either 15 amp or 20 amp and have 14 gauge 14 awg and 12 gauge 12 awg conductors respectively. 1 2 to 1 1 4 158pm. Knockout non metallic push in connector.

The national electrical code article 314 contains complete details and tables of electrical box sizes in dimensions and cubic inches and should be consulted for complete accuracy because the actual size of the box required in cubic inches depends on the number of wires that will be within that enclosure. To determine the actual opening for this size you need to add 3 8ths of an inch which is 7 8ths of an inch opening. It houses a single electrical switch or outlet and comes in metal or nonmetallic units. Here are the maximum box fill limits for a few common sizes of electrical boxes.

Knockout holes or knockouts in electrical boxes are made at the factory and have standard sizing to match cable clamps. Notes to the table above. A standard rectangular shape is the most common electrical box. I plan to install a lot of electrical conduit.

But sometimes the standard knockout openings in a wall box aren t large enough for the cable clamp or conduit fitting you need to attach to the box so you have to enlarge the hole. 1 2 to 2 179pm. Electrical boxes conduit fittings. 1 1 2 to 2 159pm.

I have posted the hole saw and knockout sizes for electrical conduit below. Hydraulic punch driver straight 90 deg. For example if you have a 7 8 hole you ll need a 1 2 knockout plug. These boxes protect wiring from the elements with gaskets sealed seams and watertight covers.

First determine the size of the missing knockout hole and subtract 3 8 to figure out what size knockout plug you ll need. An example is 1 2 inch 1 3 cm trade size.