What Gauge Wire Should I Use To Install My Sensors?

When it comes to wire gauges, the higher the number, the smaller the wire conductor. The recommend gauge wire for alarm components is solid or stranded 22 AWG, 2 conductor wire (black and red) or 22 AWG, 4 conductor wire ( black, red, green and yellow or white). Solid copper wire does not bend as easily as stranded wire, but eliminates the chance of a loose strand of wire causing a short. 22/4 wire can still be used on devices that require only 2 wires.

While some alarm devices require only 2-conductor wire, others require 4.

Non-powered devices such as doors, and windows, require only 2 wires. The AC transformer for the system also requires 2 wires as do bells and strobes. Some sirens can use 3 (red, black and yellow) but typically also use only 2.

Powered devices such as keypads, motion detectors, glass break sensors, hardwire zone expanders, wireless receivers, and relay modules all require 4 conductor wire, 2 for power, and 2 for data, or for the zone wiring. Running a phone line for line seizure also requires 4 wires.

Always refer to the device installation manual for complete instructions.

22/4 wire can be used on devices that require only 2 wires, using only two of the conductors.

22 gauge wire should not be used for smoke detectors, or for AC power to the control panel. Smoke detectors and AC transformer wires should be 18 AWG or larger. Always review the manual for smoke detectors and the local fire codes when installing smoke detectors.

Whenever possible, every door or window contact should be wired as an individual zone. Doors tend to get much heavier use than windows which causes wear and tear on the contact and can lead to false alarm issues. These issues are much easier to troubleshoot when windows and doors are wired separately from each other. Using a sharpie, each wire should be marked and labeled at the control panel box as it is connected to avoid confusion down the road.

It’s best to check with the local Fire and Building departments when pre-wiring during new construction, as specific color and gauge may be required.