What is the typical electrical wire size used for telephone circuits?

The typical electrical wire size used for telephone circuits is #22 A.W.G. This wire size is commonly chosen for most telephone wiring because it strikes a good balance between resistance and current-carrying capacity. A.W.G. stands for American Wire Gauge, which is a standard system for measuring the diameter of electrical wires.

Using #22 A.W.G. wire ensures that the signal integrity is maintained over typical distances used in residential and commercial phone installations. It offers enough conductor capacity for the low-voltage currents that telephone systems operate on while minimizing signal loss and attenuation.

Larger wire sizes, such as #18 A.W.G. or #20 A.W.G., could potentially be used but are often not necessary for the low power requirements of telephone systems. Conversely, smaller sizes like #24 A.W.G. may lead to increased resistance and potential issues with signal quality, especially over longer distances. Therefore, #22 A.W.G. is the most favorable choice for telephone wiring in standard applications.