8.1 Circuit Transient Surges, Arc Suppression & Voltage Surge Protection
Protective devices shall be used to limit surge current (back EMF). All relay and solenoid coils shall have built-in or exterior mounted circuitry to limit surges. Such circuitry (e.g., diodes, resistor, varistor, zener-zener) shall be located at the coil.
8.2 Continuous Current
Derating of continuous current is dependent upon the load type. If a relay is used to switch a combination of loads, the dominant load shall be used for derating purposes.
8.3 Coil Energizing Voltage
The voltage to energize or trigger the relay shall be at least 110% of the minimum rated energizing voltage.
8.4 Coil Dropout Voltage
The voltage to dropout or un-trigger a relay shall be less than 90% of the maximum rated coil dropout voltage.
8.5 Shock-Vibration
Special mounting considerations are necessary for mechanical relays in high temperature or vibration environments. Relays shall not unintentionally switch even during worst case operating conditions.
Last updated 01/14/04
