A polarized relay as an aircraft control element

In order to be suitable for use as an aircraft control element a polarized relay must have characteristics enabling it to meet environmental conditions and performance requirements. The characteristics of a currently used polarized relay having single-pole double-throw normally open contacts, and an inherently well balanced floating armature supported by a torsional spring, may be summarized as follows: 1. Sensitivity. Relays have been produced requiring an input of 40 microwatts (1.3 ampere-turns) to close the contacts. Somewhat less sensitivity has been found preferable for many applications.