This part of IEC 63522 is used for testing all kind of relays within the scope of technical committee 94 and shall evaluate their ability to perform under expected conditions of transportation, storage and all aspects of operational use. The object of this test is to define a standard test method for thermoelectric electromotive force(e.m.f.). Note: If different metals are attached at both ends and the temperatures where the metals are connected are held at different temperatures, current will flow in one direction in the circuit. The electromotive force that causes this current is called thermoelectromotive force.