ZB Overload Relays Protects the motor against phase failure or overload Short circuit protection when fitted directly to a contact Suitable for protection of Atex motors Single phase sensitivity to IEC/EN 60947 When fitting overload relay remote from contactor or using more than one overload relay, use remote mounting base (stock no. 493-0488 - ZB32 only) Note ZB12 have 5 pins, ZB32 have 4 pins.