Which wire can save a few dollars if you have many windows?

• A. 18/2
• B. 18/1
• C. 14/1
• D. 22/2

Answer: (D)

Choosing the smallest practical wire gauge that still fits the device needs saves money, especially when you’re installing many windows. Window sensors draw only a tiny current, so a thin two-conductor cable is usually enough to carry the signal back to the panel. Using thinner wire reduces material cost per foot, and when you multiply that across many windows, the savings add up. Thicker wire costs more and isn’t necessary for these low-current circuits, and a single-conductor approach wouldn’t give you a complete two-wire circuit for the sensor. So the most cost-effective choice for lots of windows is the small-gauge, two-conductor cable.