DS3800HACA GE

Technical Specifications

• Product Type: High-Amplitude Current Analog Output Board

• Part Number: DS3800HACA

• 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 50mA per channel (sourcing or sinking)

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

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

• 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

• Isolation: 2500Vrms reinforced isolation (logic-to-output)

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

• MTBF: > 150,000 hours (MIL-HDBK-217F)

Key Features & Advantages

• High Drive Capability: The GE DS3800HACA delivers up to 50mA per channel, suitable for driving multiple field devices in parallel or long cable runs.

• Loop-Powered Outputs: Integrated 24Vdc loop power eliminates the need for external power supplies for 4-20mA loops.

• High Compliance Voltage: 24V compliance allows driving loads up to 600Ω, accommodating most industrial field devices.

• Sourcing or Sinking: Jumper-selectable sourcing or sinking modes for flexibility with different device configurations.

• Reinforced Isolation: 2500Vrms for ground loop protection and safety in industrial environments.

• Comprehensive Protection: Over-current, short-circuit, and reverse-polarity protection safeguards the board and field devices.

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

Typical Application Cases

• I/P (Current-to-Pressure) Converters: The GE DS3800HACA drives I/P converters that control pneumatic valve actuators in process applications.

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

• Long-Distance Transmitter Powering: Supplies loop power and control signal to remote transmitters over distances up to 1000m.

• Variable Speed Drives (VSDs): Provides 4-20mA speed reference signals to VSDs controlling pumps and fans.

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

Competitive Comparison

The GE DS3800HACA is the only Mark IV board specifically designed for high-current loop-powered 4-20mA applications, with integrated loop power and high compliance voltage.

Selection Guidelines & Precautions

1. Loop Configuration: Verify whether your field devices require sourcing or sinking configuration. Set jumpers on GE DS3800HACA accordingly. Incorrect mode will result in no output signal.

2. Load Resistance Calculation: The GE DS3800HACA can drive up to 600Ω at 20mA. Calculate total loop resistance (device + cable). If exceeding 600Ω, the output will saturate.

3. Loop Power: The internal 24V loop power is isolated. Ensure the field device does not have its own power supply to avoid conflicts.

4. Cable Length: The GE DS3800HACA can drive cables up to 1000m. For longer runs, consider reducing load or using a repeater.

5. Short-Circuit Protection: While protected, repeated shorting may affect long-term reliability. Check wiring before power-up.

6. Reverse Polarity: The GE DS3800HACA is reverse-polarity protected; however, verify wiring to avoid unnecessary fault indications.

7. Commissioning: Use a precision current meter to verify each channel’s output during startup. Calibrate if necessary using onboard trimmers.

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

9. ESD Handling: Use ESD-safe practices.

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

    • All 4 channels tested at 4mA and 20mA

    • Load regulation test (up to 600Ω)

    • Loop power verification (24V)

    • Sourcing/sinking mode verification

    • Over-current and reverse-polarity protection validation

    • Isolation test (2500Vrms)

11. Spare Strategy: Keep one spare GE DS3800HACA on-site if you rely on 4-20mA control for critical actuators or positioners.