Example Operating Voltage Range Diagram for Automotive Relays
The lowest permissible input voltage at which the relay operates reliably at the reference temperature even after continuous energization (preenergizing) and brief de-energizing. Maximum voltage UII The highest permissible input voltage at the reference temperature at which the relay, with continuous energization, heats up to its max. permissible coil temperature. 
Does not take into account the temperature rise due to the contact current. E = pre-energization |