12 Volt (NO) NORMALLY OPEN RELAYS RANGE
Normally Open Relay Description
A normally open relay consists of an electromagnetic coil which actuates switch contacts . This allows a load circuit to be switched by a control circuit. The normally open relay switch contacts are open or not linked whilst the relay coil is not powered. When the control circuit terminals 85 (-ve return) & 86 (control +ve) receive power this energises the electromagnetic coil which moves to close the switch contacts and "make" the load circuit between terminals 30 (supply ) and 87 (load).