Circuit tester a must for home electrical work
Q: I would like to purchase a circuit tester for my tool kit, but I’m a little confused. I see three types at the hardware store — a small, cheap-looking tester; one that looks like a pen; and a fairly expensive type called a multitester. Which is the best type for a home toolkit? — Joseph B., Houston
A: What’s the best type for your home? Well, you should really have the first two on your list. The cheap-looking circuit tester — an item with two wires capped by metal probes on one end, and a light on the other end — is an essential safety item. With it, you can check to make sure no electrical current is traveling through a circuit before doing a repair.
A continuity tester — the one that looks like a pen, with a needle-like probe at one end and a wire protruding from the other end capped by a metal alligator clip — creates a miniature electrical circuit for testing current-carrying items. A battery is installed inside the “pen” cartridge to supply power.
To test a fuse, for example, the alligator clip is attached or held to one end of the fuse and the needle probe touched to the other end. A light inside the cartridge illuminates if the circuit is completed, meaning the fuse works. The continuity tester is useful for a variety of repairs to make sure parts will carry current.
The multitester (or multimeter) not only checks the continuity of a circuit, but also provides a more precise reading for different types of circuits to find out what level of voltage or amperes they carry.
For most minor installations and repairs, such as fixtures and switches, the multitester would only be used to check continuity. Measuring continuity (or resistance) of volts or amps in a circuit is a task for those much more experienced with electrical repairs. If you decide to invest in a multitester, get the best available and become very familiar with its operation.
In all three cases, be sure that power to the circuit being tested is turned off at the main panel. (The multitester can measure a live circuit, but I don’t recommend that task for those inexperienced with electrical repairs.)