Description
Yokogawa PW702 DCS Power Supply Module
Technical Specifications Model: PW702 Input Voltage: 100~240VAC, 50/60Hz Output: Multi-channel regulated DC output for DCS backplane bus Mounting Form: Plug-in DCS rack module Operating Temperature: 0℃ ~ +60℃ Storage Temperature: -20℃ ~ +70℃ Relative Humidity: 10% ~ 90% non-condensing Protection Function: Overvoltage, overcurrent, overtemperature protection Module Indicator: Power OK LED, Fault LED
Functional Features Wide AC input voltage range adapts to unstable industrial power grid. High capacity multi-channel DC output supports DCS rack with large quantity of I/O modules. Supports redundant parallel power supply configuration for uninterrupted control operation. Hot swap function allows module replacement without DCS system shutdown. Built-in continuous self-diagnosis function monitors power conversion hardware. Power OK LED and fault LED provide clear visual state indication. Low ripple DC output guarantees stable signal acquisition of high precision analog I/O modules. High power conversion efficiency reduces heat load inside control cabinet.
Application Scenarios Large-scale petrochemical DCS control station, coal-fired power plant boiler control rack, large fertilizer plant continuous process control system, oil refinery process monitoring DCS rack, large-scale LNG plant control platform.
Performance Parameters Output voltage maintains stable value within tolerance range with AC input fluctuation. Low voltage ripple under full rated load condition. Protection circuit triggers fast shutdown upon overvoltage, overcurrent and overtemperature fault. Redundant parallel mode realizes bumpless power switchover during single module failure. Self-diagnosis reliably captures internal power hardware fault. Module maintains stable power output performance during long-time continuous running.
Material Composition Module housing: Black flame-retardant engineering plastic. Main PCB: FR4 multi-layer industrial printed circuit board with conformal protective coating. Core electronic components: AC-DC switching power chip, high frequency transformer, rectifier diode, filter capacitor, power monitoring IC, protection circuit chip. Connector: Gold-plated edge connector for DCS rack backplane. Indicator: Light emitting diodes for power and fault state. Fasteners: Plastic positioning buckle.
Structural Features Rectangular plug-in module designed for Yokogawa DCS rack slot. Front panel equipped with power OK LED and fault LED indicators. Gold-plated edge connector on rear side connects to rack backplane bus. Internal circuit separates high voltage AC input zone and low voltage DC output zone with isolation barrier. Ventilation holes on housing for natural convection heat dissipation. Side positioning buckle ensures accurate insertion and locking on rack slot.
Working Principle AC power enters PW702 module through DCS rack backplane connector. EMI filter suppresses power grid interference signal. High-frequency switching circuit converts AC power into isolated multi-channel DC voltage. Rectifier and filter circuit smooth DC output ripple. Voltage feedback circuit continuously samples output voltage and adjusts switching duty cycle to stabilize output. Overvoltage, overcurrent and overtemperature monitoring circuit runs in real time. Once fault threshold is exceeded, protection circuit cuts off power conversion and triggers fault LED alarm. Two PW702 modules can run in redundant parallel mode, each module can independently bear full rack load. When one module fails, seamless power switch occurs and DCS system continues running without interruption.
Installation Requirements Cut off rack main power before installing or removing PW702 module. Align module with empty DCS rack slot, push inward steadily until backplane connector fully inserts and buckle locks. Connect AC power cable to rack power terminal according to wiring specification. Power on rack and verify LED indicator state. Install two PW702 modules in designated slots for redundant configuration. Reserve ventilation clearance around module to avoid heat accumulation. Carry out redundant power switchover test in system commissioning stage.
Usage Precautions Module only works with matched Yokogawa DCS rack system. Cut off rack AC power before plugging or unplugging module. Do not exceed rated output power of module. Redundant power configuration must be adopted for critical process control racks. Clean dust accumulated on ventilation openings periodically. Do not disassemble module housing without professional authorization, internal high voltage circuit exists. Replace module when continuous fault alarm appears.
