Reliance 45C321

The 45C321, also marked as 45C-321, is a dedicated power supply module for Reliance AutoMate 30/40 series PLC systems. It supplies power to the backplane and all installed CPU, I/O and communication modules. This model is discontinued. Only refurbished, surplus or NOS units are available for maintenance and replacement of legacy systems.

45C: Unified prefix for Reliance AutoMate 45C-series control components.321: Designates the high-power power supply module of this series.No suffix: Indicates the original hardware version. Versions marked with A/B/C/D are revised editions with optimized circuits and heat dissipation performance.Hyphen: Standard format for industrial part numbers, and it will not change product functions.

Input Voltage: Auto-adaptive 120 / 240 VAC.Output: Multiple DC outputs for backplane, including 24VDC with 20A peak current.Rated Power: Approximately 480W.Efficiency: Above 90% with power factor over 0.9.Operating Temperature: -10°C to +55°C.Dimensions: About 96.5×70.5×56.5 mm.Weight: Approximately 2.9 kg.Slot Occupation: Occupies 2 slots when installed on 45C31x series racks.Protection Features: Overvoltage, overcurrent, overheating and short circuit protection.

Module Installation: Side-loading design compatible with standard AutoMate racks and fixed with screws.Backplane Connection: Edge connectors deliver power and timing signals to the backplane directly.Front Panel: Equipped with power switch, key lock and status indicators including PWR, OK and FAULT.Terminal Block: Used for AC input connection, grounding and auxiliary alarm contacts.

Converts 120/240VAC into stable multiple DC voltages required by the PLC backplane.Provides 24VDC / 20A power supply for CPU, I/O and communication modules.Controls power-up sequence to ensure orderly system startup.Detects operating faults and activates protection mechanisms. The FAULT indicator will turn on once abnormalities occur.Monitors power status and communicates with the backplane for overall system management.

Replacement and expansion of 2-slot power supply modules in legacy AutoMate 30/40 series PLC systems.Maintenance of old industrial systems such as manufacturing lines, process control, water treatment, metallurgy and petrochemical industry.Applied to high-density I/O racks including 16-slot and 19-slot models that require high-current 24VDC power supply.Suitable for critical control circuits demanding high reliability and long continuous operation time.

Installation: Cut off system power before inserting the module into two adjacent slots and tighten the fixing screws. Keep sufficient space for ventilation.Wiring: Connect AC power and ground wire to the terminal block. Confirm the selected input voltage matches the on-site power supply.Power-on Operation: Turn on the power switch. The PWR indicator lights up. The OK indicator stays on and the FAULT indicator turns off after self-check completes.Routine Maintenance: Clean dust on fans and heat sinks every quarter. Regularly check terminal tightness and ensure edge connectors are free from oxidation.Safety Notes: Disconnect AC power and wait for complete discharge before disassembly or maintenance to avoid electric shock.