Electrical Box Punch Out Sizes

Notes to the table above.

Electrical box punch out sizes.

Mophorn 10 ton 1 2 to 2 hydraulic knockout punch driver tool kit electrical conduit hole cutter set ko tool kit with 6 dies hole complete tool knockout punches by mophorn 71 99 71. If you punch out the wrong hole you can fill it with a knockout seal. For example if you have a 7 8 hole you ll need a 1 2 knockout plug. Different electrical box sizes fit varying installation needs.

A screw type or manual knockout punch is tightened with a wrench to knock out the hole. Codes also limit the number of wires that can enter an electrical box or electrical receptacle depending on the inside volume of the box and the gauge of the wires. If you punch out too big of a hole you can use reducing washers. Box typical inside dimensions are about 2 in.

It houses a single electrical switch or outlet and comes in metal or nonmetallic units. The draw bolt is turned by a wrench to pull the punch through the metal making the hole. Electrical trade sizes and plumbing trade sizes are equal and are based on pipe sizes. In the electrical panel above the inner 3 4 knockout was the easiest to punch out first.

A standard rectangular shape is the most common electrical box. First knockout punched inward for removal. An example is 1 2 inch 1 3 cm trade size. Bx cutters after cutting out some concentric knockouts.

First determine the size of the missing knockout hole and subtract 3 8 to figure out what size knockout plug you ll need. Standard piece makertm punch and conduit size actual punched hole diameter in 1560. The 3 4 inch 1 9 cm trade size is a 1 1 8 inch 2 9 cm opening. The shape of an electrical box can help you identify its purpose.

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. Temco th0390 manual knockout punch driver kit set for inch to 2 inch electrical conduit hole sizes 1 2 2 conduit size 4 7 out of 5 stars 56 84 95 84.