GE DS3820PSLA

Key Parameters

• Channels: 4 isolated analog inputs

• Sensor Type: Pt100 (2‑wire, 3‑wire, or 4‑wire – software‑configurable per channel)

• Resolution: 24‑bit ADC

• Accuracy: ±0.05°C (Pt100, 25°C); ±0.2°C over –40°C to +70°C

• Excitation Current: Software‑selectable 0.1 mA, 0.5 mA, 1 mA (per channel)

• Excitation Power: Line‑powered (AC/DC wide‑range input, 85–265 V AC or 110–300 V DC) – eliminates need for separate 24 V DC field supply for sensors

• Lead Resistance Compensation: Automatic for 3‑wire and 4‑wire configurations

• Measurement Range: –200°C to +850°C

• Sampling Rate: Up to 50 Hz per channel (with 50/60 Hz noise rejection)

• Diagnostics: Open‑circuit detection, short‑circuit detection, over‑range/under‑range, signal‑loss detection, per‑channel LED status

• Isolation: 1500 V RMS (field‑to‑backplane); 500 V RMS between channels (per‑channel isolation)

• Terminal Type: Screw‑type – per suffix “A”

• Power: 85–265 V AC / 110–300 V DC (internal power supply) – consumes ≤6 W

• Operating Temperature: –40°C to +70°C

Advantages

• Line‑powered excitation – directly powered from AC/DC mains; eliminates the need for a dedicated 24 V DC field supply for sensors, simplifying wiring and reducing panel cost.

• Long‑distance capability – line‑powered excitation provides stable drive current unaffected by cable voltage drop; ideal for sensors located far from the control panel.

• Premium accuracy – ±0.05°C; high precision for demanding applications.

• 24‑bit resolution – provides superior measurement fidelity.

• Per‑channel isolation – 500 V between channels; prevents ground loops and cross‑channel interference.

• Automatic lead compensation – for 3‑wire/4‑wire RTDs, cancels lead resistance errors for accurate temperature readings.

• Software‑configurable per channel – wire configuration and excitation current independently settable.

• Built‑in linearization – provides direct temperature readout in °C or °F; no scaling required.

• Enhanced diagnostics – includes signal‑loss detection for proactive maintenance.

• Open/short detection – detects broken wires or sensor shorts instantly.

• Hot‑swappable – replace without rack power‑down.

• Wide measurement range – –200°C to +850°C covers most industrial applications.

Applications

• Remote temperature monitoring – pipelines, tanks, and outdoor installations where sensors are located far from the control panel

• Oil & gas – wellhead and pipeline temperature monitoring with long cable runs

• Water/wastewater – remote pump station and lift station temperature monitoring

• HVAC – building‑wide temperature monitoring with distributed sensors

• Power generation – substation and transformer temperature monitoring

• Mining – remote equipment temperature monitoring

• Marine & offshore – engine room and deck temperature monitoring with long cable runs

• Chemical processing – tank and vessel temperature monitoring in large plants

Competitor Comparison

The DS3820PSLA is the long‑distance, line‑powered variant of the Pt100 input family. Compared to 24 V‑powered modules like the DS3820PSFA, it eliminates the need for a separate 24 V field supply and maintains stable excitation over long cable runs – critical for remote sensor installations. While it offers a lower sampling rate (50 Hz vs. 200 Hz), this is typically not a limitation for static or slowly changing temperature applications. For temperature monitoring in large facilities with distributed sensors, the DS3820PSLA delivers the most reliable and cost‑effective solution.

Selection Tips

• Choose DS3820PSLA when your Pt100 sensors are located far from the control panel (long cable runs) or when a separate 24 V DC field supply is unavailable.

• Ideal for pipeline monitoring, remote tanks, outdoor installations, and large‑scale building automation.

• Verify the wire configuration (2‑wire, 3‑wire, or 4‑wire) – software‑configurable per channel.

• For 2‑wire sensors, lead resistance adds error – use 3‑wire or 4‑wire for accurate measurements.

• Not suitable for Pt1000, Ni RTDs, or thermocouples – use dedicated modules.

• Ensure your PLC/DCS can handle the data format from DS3820PSLA.

Precautions

• Line power connection: The DS3820PSLA requires 85–265 V AC or 110–300 V DC mains power – ensure proper fuse and overcurrent protection on the supply line.

• Power consumption: The module consumes up to 6 W; ensure adequate cooling in dense racks.

• Lead resistance: For 2‑wire sensors, lead resistance directly adds error – use 3‑wire or 4‑wire for accurate measurements. The DS3820PSLA compensates for 3‑wire/4‑wire automatically.

• Excitation current: Higher currents (1 mA) produce self‑heating errors in small Pt100 elements – use 0.1 mA or 0.5 mA for sensitive sensors.

• Wiring: Use shielded twisted‑pair cables; ground shield at module end only. For 4‑wire, use separate pairs for excitation and sense leads.

• Signal‑loss detection: Requires minimum sensor impedance – very low‑impedance sensors may not trigger detection.

• Power sequencing: Apply mains power before backplane power to avoid power‑up transients.

• Calibration: Perform periodic calibration using precision resistors to maintain accuracy.

• Spare: Keep one spare DS3820PSLA for critical remote temperature loops – the line‑powered variant may have longer lead times.