GE DS3800NHVJ1A1A

Key Technical Parameters

Advantages and Distinctive Features

• Hybrid Output + Tachometer Feedback: Combines 8 high-voltage DC relay outputs (125VDC), 4 high-current solid-state outputs (3A), AND 2 tachometer inputs on a single board.

• Higher Solid-State Current (3A): Supports larger 48VDC auxiliary fans compared to 2A boards.

• Higher Relay Current (2A @ 125VDC): Supports more powerful 110–125VDC fans.

• Enhanced Temperature Accuracy (16-bit ADC): ±1°C accuracy as standard.

• Improved Cold-Junction Compensation: More reliable temperature measurement.

• Enhanced Tachometer Filtering: Reduces false speed failure alarms.

• Baseline Revision A: The original version of this high-capability hybrid board.

Typical Application Fields

• Safety-Critical 125VDC Cooling Systems: Where fan failure must be detected immediately.

• High-Voltage Industrial Fan Systems: 110–125VDC exhaust fans with higher-power 48VDC auxiliary controls and speed monitoring.

• Military & Naval Applications: 125VDC systems in shipboard environments.

• Railway and Traction Applications: 110VDC cooling systems with 48VDC auxiliaries.

• Legacy Turbine Installations: Older systems using 125VDC fan motors.

Comparison with Related Models

Selection Recommendations

• Choose the DS3800NHVJ1A1A if:

  • You need 125VDC relay outputs with 2A current capacity for more powerful fans.

  • You also need higher-current solid-state outputs (3A @ 48VDC) for larger auxiliary fans.

  • You require tachometer feedback for fan speed verification.

  • You want enhanced temperature accuracy (±1°C) and improved filtering.

  • You have a climate-controlled environment (0°C to +60°C).

  • You need a direct replacement for an existing DS3800NHVJ board.

• Choose the DS3800NHVH1B1B if: You need 2A @ 125VDC relays and tachometer feedback but can accept 2A solid-state outputs and require extended temperature range (-20°C to +65°C).

• Choose the DS3800NHVF1B1A if: You need 250VDC relay outputs (1A) with hybrid + tachometer features.

Critical Precautions

• ESD Protection: Always wear a grounded wrist strap.

• High-Voltage Hazard: Relay outputs switch 125VDC—lethal voltage present on terminals. Observe all high-voltage safety procedures. Use wiring rated for ≥125VDC.

• DC Polarity (Relay): Relay outputs are DC only—observe correct polarity.

• DC Polarity (SS): Solid-state outputs are DC-only and polarity-sensitive—reverse polarity destroys the MOSFET.

• Tachometer Wiring: Use shielded twisted-pair cable. Connect shield to designated terminal—not at the fan end.

• Relay Current Limitation: Rated at 2A continuous @ 125VDC. Verify fan current does not exceed this limit.

• SS Current Limitation: Rated at 3A continuous @ 24–48VDC. At elevated temperatures, consider derating.

• Inductive Load Derating (Relay): Derate to 1.5A or use external RC snubbers (rated for 125VDC).

• No AC Connection: Do not connect AC loads to either output type.

• No Hot-Swap: Always depower the rack before insertion/removal.

• Slot Assignment: Install in slots 8–10 (auxiliary I/O).

• CPU Dependency: If backplane communication is lost, the board defaults to 100% fan speed—tachometer monitoring disabled in fallback mode.

• Firmware Compatibility: The DS3800NHVJ1A1A is compatible with Mark V CPU firmware v4.0 and above for full 16-bit ADC functionality. For v3.x, the enhanced ADC features may be partially disabled—confirm compatibility before purchasing.