Fixing and testing low-voltage systems: handy tips

Devices that run on low voltages, like remote controls, are often battery-powered. Here are a few handy tips for fixing low-voltage systems and how to test them.

• If you have no electrical training, only repair battery-powered systems, where there is little or no chance of receiving an electric shock.
• Check the power switch first. Make sure that the contacts are meeting as they should, and that they're free of rust. Clean off any corrosion with fine sandpaper.
• If you experience even the slightest shock from an appliance, run a multimeter wire to a reliable ground, and touch the casing of the appliance with the other probe. If any voltage is present, don't use the appliance until the fault has been fixed.
• Dirty or damaged battery contacts are a common cause of equipment failure. Use fine sandpaper to polish the contacts within the equipment as well as the battery ends themselves.

• A battery-operated multimeter allows you to test if an electrical circuit, plug, switch, element or battery is fully functional.
• Compact digital models are much simpler to use than old-style analog meters, and will automatically sense and set the range in ohms, amps or volts, as relevant to the particular test.

• Unplug the appliance you'll be testing and turn it on.
• Ensure that your multimeter is set to its lowest range in ohms (usually RX1) and touch the probes to the plugs.
• A reading in the range 20 to 100 means the circuit is functional.
• If your read out is above or below that range, replace the plug and cord, or buy a new appliance.

• Remove the element from the stove.
• Ensure that the meter is set to its lowest range in ohms (usually RX1) and touch the probes to both of the element's terminals.
• A reading in the range 20 to 100 means the element is functional.
• But if your read out is above or below that range, replace the element.

• Ensure that your meter is set at a slightly higher DC voltage than the battery you'll be testing.
• Then, with the battery inside the device its powering, touch the terminals with the probes (red to +, black to –).
• If the reading is 20 percent or more below the battery voltage, replace the battery.

Remember these handy tips and testing guide, and you'll be on your way to being more savvy around low-voltage systems.