BHEL UN0610AV1 Auxiliary Power Supply Module (PN: 69203NA1AA)

1. Product Description

UN0610AV1 with factory part number 69203NA1AA is a VME-format rack-mounted auxiliary power supply PCB manufactured by BHEL for DATATRONIC generator excitation & turbine control racks. It works cooperatively with UN0660AV1, UN0661AV1 and UN0662AV1 DVR control cards to provide stabilized multi-channel isolated DC power for all excitation signal conditioning circuits. This vertical single-slot plug-in board weighs approximately 520g, with full conformal coated PCB to resist dust, humidity and corrosive flue gas inside power plant control cabinets. It accepts 24VDC input from rack backplane bus and converts to multiple isolated low-voltage DC rails for analog amplifiers, signal transformers and digital logic chips. The dark metal front panel integrates power status LED indicators and front test terminals for voltage calibration, dual metal ejector latches support hot-swap maintenance without full rack power shutdown. Rear high-density dual-row VME gold finger bus communicates with rack master CPU for power fault reporting, compliant with industrial EMC and power station safety standards.

2. Core Product Functions

• 24VDC rack input conversion to multi-channel stabilized isolated DC power rails for the entire UN066x series DVR control cards
• Built-in overvoltage, undervoltage, overcurrent and short-circuit protection for each output channel to prevent damage to signal conditioning circuits
• Multi-stage EMI filtering at input and output sides to suppress power supply noise interference on voltage and current sampling signals
• Real-time power rail monitoring; detect abnormal voltage drop or loss of any auxiliary power output channel
• TMR redundant power cross-checking in triple redundant excitation racks, synchronize power status data with three UN0610AV1 modules
• Galvanic isolation between main rack 24VDC input and sensitive analog measurement power supplies to block high-voltage grid EMI
• Transmit power supply fault codes, output voltage status and protection trip signals to rack master CPU via VME backplane bus, upload alarm records to plant DCS monitoring system

• Hot-swap compatible design for redundant racks; faulty power module can be replaced online without interrupting generator excitation control operation

  
  

3. Application Scenarios

• Coal-fired thermal power plant steam turbine generator static excitation control cabinets
• Combined cycle gas turbine power plant compound AVR regulation racks with UN066x series control cards
• Large hydropower station synchronous generator triple redundant voltage control systems
• Refinery, petrochemical and offshore platform self-generation turbine excitation protection panels
• Heavy industry captive power plants equipped with BHEL DATATRONIC turbine & generator control systems

4. Common Troubleshooting & Typical Issues

• Continuous Auxiliary Power Loss Fault Alarm

  Causes: Unstable 24VDC rack input voltage, internal power conversion circuit burnout, short-circuit load from faulty DVR signal card. Solutions: Stabilize rack DC power supply, inspect downstream UN066x cards for short-circuit faults, replace defective UN0610AV1 power module.

• Generator Voltage Hunting Caused by Power Noise

  Causes: Damaged internal EMI filter capacitors on UN0610AV1, deteriorated isolation circuits introducing switching noise into measurement loops. Solutions: Replace UN0610AV1 power board, recheck grounding of all DVR signal cards.

• TMR Power Status Voting Discrepancy Alarm

  Causes: Uneven output voltage offset among three UN0610AV1 modules, poor VME backplane contact. Solutions: Recalibrate each power module output voltage, clean gold finger connectors with anti-static cloth.

• Module FAIL LED Steady Red, No Auxiliary Power Output

  Causes: Internal switching MOSFET burnout, blown fuse on input rail, corrupted power monitoring logic circuit. Solutions: Inspect input fuse status, replace faulty UN0610AV1 module.

• Frequent Overcurrent Protection Trip

  Causes: Short-circuit in UN0660/661/662 signal circuits, overloaded power output channels. Solutions: Disconnect each downstream DVR card one by one to locate short-circuit fault point, repair or replace faulty signal card.