Description The Edwards EST 3-CPU3 is a central processing unit module designed for EST3 life safety and fire alarm systems. It supervises all local rail modules, manages inter-module communications, and provides the network interface for system-wide data exchange. With integrated non-volatile memory and advanced diagnostic features, the 3-CPU3 ensures reliable system control and coordination. Technical Specifications Condition New/Never Used Surplus Brand Edwards / EST Category PLCs/Machine Control Part Number 3-CPU3 Subcategory PC Board PLC/Add-On Board Processor Type 16-bit CPU Memory Non-volatile, 1,000 event history storage Communication RS-485 (network), RS-232 (maintenance/expansion) Relays 3 × Form-C relays, 30 VDC @ 1 A (alarm, supervisory, trouble) Audio Support 8-channel digital audio subsystem command/control Event Stamping Integrated calendar/clock with leap-year adjustment Voltage Requirement 24 VDC Current Draw 145 mA standby / 155 mA alarm Mounting Occupies first two slots of 3-CHAS7 rail chassis Indicators/Functions Ground fault detection, watchdog supervision Connections Plug-in connectors, power-limited and transient protected Operating Temp 32°F to 120°F (0°C to 49°C) Humidity Range Up to 93% RH, non-condensing Dimensions Standard rail-mounted CPU module size Weight 1.37 lbs Information About 3-CPU3 The 3-CPU3 is part of the Edwards EST3 modular fire alarm and life safety system. Occupying the first two slots of the 3-CHAS7 chassis, it serves as the master controller for local modules and as the communication hub for networked panels. The CPU automatically learns the configuration of installed modules, downloads operating parameters, and supports firmware upgrades without hardware replacement. It features RS-485 and RS-232 communication options, multiplexed audio support, and Form-C relays for alarm, supervisory, and trouble signaling. With watchdog monitoring, non-volatile memory, and built-in time/date event stamping, the 3-CPU3 provides both system intelligence and operational resilience. Key Features: Central System Processor: Controls and supervises all modules within the EST3 chassis. Automatic Module Learning: Detects and configures rail modules at startup. Integrated Memory: Non-volatile storage with support for 1,000 history events. Multiple Communication Options: RS-485 for network, RS-232 for local connections. Relay Outputs: Three Form-C relays for alarm, supervisory, and trouble. Watchdog and Diagnostics: Monitors hardware and software faults for enhanced reliability. Audio Control Support: Provides command and control for 8-channel digital audio subsystems. Firmware Upgradable: Software and firmware updates loaded directly through the CPU. The 3-CPU3 provides the processing intelligence and communication backbone essential for EST3 networked fire alarm and life safety systems.
