The ELR150 Series is a power supply REQUIRED to control ELR Devices. The power supply contains a Motherboard that will accept up to four plug-in Control Modules. Each Control Module (part CM150-08) controls one ELR Device and includes a Time Delay Feature. The Time Delay provides a variable (0-4 minutes) Latch Retraction period in response to a momentary input. Circuit breakers provide protection for Motherboard. 115 or 230 Volt user selectable switch. LED Indicator provides clear indication that power is available to the supply. Keyed cabinet to maintain safety and security, each power supply is equipped with a preinstalled key-cylinder. UL Listed for Class II Output, conforms to UL 294 standards incorporating enhanced access control communication capabilities.