Noncontact voltage testers a safe option

DEAR TIM: I’ve always been afraid of electricity. I know I can’t be alone. I’m trying to overcome this fear and wonder if you can help me. What would you do if you were me? Are there simple tools I can use to help tell me when I’m close to a wire or cable that has electricity in it? How effective are they? Are they safe and easy to use? I’ve seen something that looks like an oversized pen that says it can detect a live electrical circuit without touching the actual wire or cable. Would you use one of these? – Carla P., Albany, New York

DEAR CARLA: Your fear of electricity is fairly common based on the number of emails I receive about it. My gut tells me the fear is based on the fact you can’t see electricity in most instances and it’s a known killer. Even though I don’t really fear electricity in my home, I have a keen and healthy respect for it.

You may never get over your fear of it, but I congratulate you for facing the fear and giving it a try. The first step, in my opinion, is to read about electricity and have a good understanding of how it works and why it would want to pass into and through your body. You may want to look into classes offered at local vocational schools to gain some formal training as well.

Voltage testers and meters have been around for years, but most of them had two probes or tips that required you to be in contact with the electrical wire to check its voltage. These require a certain level of skill to operate, and for a person with a fear of touching a live electrical circuit, using one of these would no doubt be a deal breaker.

Fortunately, tool manufacturers have responded to this fear and have developed noncontact proximity voltage testers. These testers are made for folks like you who just want to get a tool close to a wire to see what’s going on.

I’ve had the opportunity to test several of these magical and safe tools. The latest one on the market intrigues me for a number of reasons. I recently had the opportunity to test the rugged NCVT-3 made by Klein Tools. The acronym, NCVT, stands for noncontact voltage tester. You’d think they made the tool for you!

This little tester is about the size of a large felt-tipped marker pen and comes with a clip to fit into a shirt pocket. It operates on two AAA batteries. A handy, small LED flashlight is also built into the tool so you can operate it in a low-light environment safely.

This tool is perfect for a homeowner because it can sense voltages between 12 and 1,000 in alternating current (AC). The electricity you have in your home is almost always AC, as I’ve never in my life seen a home that uses direct current (DC) to power everything. The common voltages in a residential home in the U.S. are 120 and 240 volts so this new tool will tell you all you need to know around your home.

The tool has five vibrant LED light bars as well as an audible tone beeper that alerts you when the tool senses the presence of electricity in the 12- to 1,000-volt AC range. The more voltage present, the more bars light up and the faster the tool beeps at you.

One of the things you’ll love about this tool is how it works as you get closer to a live wire. I tested it extensively, and it seems to start to sense live electricity about 2 inches away from the wire.

Here in my office I tested the 120-volt power cord that feeds my inkjet printer. When I got within 2 inches of the cord, one of the yellow LEDs came on and the beeper slowly beeped at me. As I got the tip closer and closer to the power cord, a second LED lit up and the beeping increased. When I finally touched the tip of the tester to the safe power cord, a third red LED light came on and the beeping turned into a constant audible tone.

I went around my house and started putting the tool on the drywall near light switches that were in the on position. Sure enough the tool was able to sense voltage through the drywall. The wires must have been close to the other side of the drywall for this to happen as Klein Tools says the effective range of the tool is 2 inches.

This NCVT-3 has an automatic power off function to save the batteries in the tool. This is a very handy feature. The tool can survive a drop of up to 6.6 feet. If you plan to use it up working on a step ladder, I’d tie a string to the pocket clip and then tie the other end to a belt loop. Accidents can happen and there’s no need for the tool to fall to the ground if you just use some common sense.

Dust and water will not harm the tool. I can tell you this is a tool that can last generations if you just treat it with moderate care. It’s that durable.

If you decide to invest in this tool, be sure you always test it on a live circuit so you know it’s working properly. I’d suggest doing what I did by testing it on a power cord that’s plugged in and the appliance or electronic device is drawing a small amount of power. My inkjet printer has a tiny blue LED light that sucks power as the printer is on standby so I know that there’s power flowing through the power cord from the wall outlet to the printer.

You can test it on a toaster power cord as you’re browning up your bread for breakfast. When you turn the toaster on and see the orange glow of the heating elements, turn on your NCVT-3 and start to get it close to the power cord. I’ll bet you have a grin on your face in about two seconds as you safely see the presence of the electric in the power cord. Have fun and be safe!