GE DS3800HACB

Technical Specifications

• Product Type: High-Amplitude Current Analog Output Board

• Part Number: DS3800HACB

• Manufacturer: General Electric (GE)

• System Compatibility: GE Speedtronic Mark IV Turbine Control Systems

• Output Channels: 4 independent analog current outputs

• Output Type: 4-20mA or 0-20mA (jumper-selectable), loop-powered

• Drive Capability: Up to 60mA per channel (sourcing or sinking)

• Loop Power: Internal 24Vdc loop power supply (isolated)

• Compliance Voltage: 24Vdc (allows driving loads up to 600Ω at 20mA; 400Ω at 60mA)

• Resolution: 12-bit

• Accuracy: ±0.1% of full scale at 25°C; ±0.02% per °C drift

• Protection: Over-current, short-circuit, and reverse-polarity protection per channel

• Diagnostics: Individual channel fault detection (open-loop, short-circuit, over-temperature)

• Isolation: 2500Vrms reinforced isolation (upgraded from 1500Vrms)

• Temperature Range: -40°C to +70°C (extended)

• Heat Dissipation: Improved thermal management with integrated heatsink

• MTBF: > 180,000 hours (MIL-HDBK-217F)

Key Features & Advantages

• Higher Drive Capability: The GE DS3800HACB delivers up to 60mA per channel, providing additional margin for driving multiple devices or longer cable runs.

• Enhanced Loop Diagnostics: Individual channel fault detection reports open-loop, short-circuit, and over-temperature conditions to the Mark IV processor, enabling proactive maintenance.

• Reinforced Isolation: Upgraded to 2500Vrms for superior ground loop and transient protection.

• Extended Temperature Range: -40°C to +70°C suits harsh environments.

• Improved Thermal Management: Integrated heatsink with thermal monitoring allows sustained high-current operation.

• Loop-Powered Outputs: Integrated 24Vdc loop power eliminates external power supplies.

• High Compliance Voltage: 24V compliance drives loads up to 600Ω at 20mA.

• Diagnostic LEDs: Front-panel LEDs indicate output status, fault, and loop power presence per channel.

Typical Application Cases

• I/P (Current-to-Pressure) Converters: Drives I/P converters for pneumatic valve actuators.

• Valve Positioners: Provides 4-20mA control signals for smart and analog positioners.

• Long-Distance Transmitter Powering: Supplies loop power and control signal to remote transmitters up to 1200m.

• Variable Speed Drives (VSDs): Provides 4-20mA speed references to VSDs.

• Damper and Louver Actuators: Controls 4-20mA actuated dampers.

Competitive Comparison

The GE DS3800HACB offers significant improvements over the HACA series, including higher drive capability, diagnostic reporting, and reinforced isolation.

Selection Guidelines & Precautions

1. Loop Configuration: Verify sourcing or sinking mode for your field devices. Set jumpers on GE DS3800HACB accordingly.

2. Load Resistance: Calculate total loop resistance. The GE DS3800HACB drives up to 600Ω at 20mA; derate to 400Ω at 60mA.

3. Loop Power: Internal 24V loop power is isolated. Ensure field devices do not have their own power supply.

4. Cable Length: Supports cables up to 1200m. For longer runs, reduce load or use a repeater.

5. Diagnostic Reporting: Verify Mark IV firmware supports diagnostic reporting from the GE DS3800HACB. Earlier firmware may ignore fault data.

6. Thermal Management: Ensure cabinet airflow is adequate (minimum 100 CFM) for sustained high-current operation.

7. Short-Circuit Protection: Protected, but repeated shorting may affect reliability.

8. Commissioning: Use a precision current meter to verify each channel. Calibrate using onboard trimmers if necessary.

9. Wiring: Use shielded twisted-pair cables; ground shield at board end only.

10. ESD Handling: Use ESD-safe practices.

11. Sourcing: Obsolete. Request functional test report including:

    • All 4 channels tested at 4mA, 20mA, and 60mA

    • Load regulation test (up to 600Ω)

    • Loop power verification (24V)

    • Diagnostic fault reporting validation (open-loop, short-circuit)

    • Isolation test (2500Vrms)

    • Thermal monitoring verification

12. Spare Strategy: Keep one spare GE DS3800HACB on-site for critical 4-20mA control applications. The diagnostic features make this the preferred choice over earlier HACA revisions.