identify a knockout when referring to electrical wiring?

Answer 1

I think it is a panel that can be removed to expose wiring.

Answer 2

A knockout is a piece of metal, round in shape, usually either 1/2 inch, 3/4 inch, or sometimes 1 inch that has been stamped into the body of the circuit box. It will have a small looking weld on the edge, and by knocking out the correct size for your installation, you have access to the metal connector box. Many different electrical devices contain various size knockouts so that you can access the center of the box where the connections are made. They are there so electrical connections can be made between various circuits coming from various locations. Frequently, man made underwriter knots will be placed in the knockout, which the wire will pass through, to keep the wires from being loosened by tugging or stress on the connections.

Answer 3

The knockout is the hole through which a fitting is inserted to bring a cable into a box by putting its cable clamp in the resulting hole. Knockouts are knocked out by putting the edge of a screwdriver into the knockout depression and hitting it with a palm or a hammer. The pierced piece of the knock out is knocked loose by that blow.

Knockouts often have an inner and outer hole, like for a 1/2" or a 3/4" fitting. If you want the smaller size you hit the center peiecing. If you want the larger one hit the outer edge.

Since you can't have an unused hole in the box (to avoid fire danger) you position the box and then knock out just the one that is in the right place.

Answer 4

A knockout is on an electrical box, or panel, it's the usually round metal piece that can be knocked out in order to run wire, or connect a romex connector to.

Answer 5

Well, there may be other definitions, but if you look at electrical boxes, they have discs cut into them around the perimeter. They are attached by a thin piece of metal or two. You whack it with a hammer to knock it out. Even a properly used screwdriver will do, for the non-violent ;-)

This allows one box to serve a multitude of functions, and still retain some fireproofing capability. Use with appropriate connectors to prevent fraying of the insulation.

Answer 6

Look at any junction box or switch panel and you'll see prestamped round shapes on the box. You can "knock-out" these pieces of metal and mount strain relief or conduit for wiring.