User Manual

Foxboro 841GX-CI1 Pressure Transmitter

Prepared exclusively for:Easy Semiconductor Technology (Hong Kong) Limited

1. Product Overview

1.1 General Description

The Foxboro 841GX-CI1 is a high-performance, 2-wire, loop-powered electronic gauge pressure transmitter. Designed for precise, stable measurement of gauge pressure in industrial process environments, it converts physical pressure into a proportional 4–20 mA DC electrical signal for monitoring and control systems.

• Brand: Foxboro (Schneider Electric / Invensys)

• Model: 841GX-CI1

• Type: Gauge Pressure Transmitter

• Output: 4–20 mA DC (2-wire loop)

• Power Supply: 12.5–36 V DC (loop-powered)

• Wetted Parts: 316L Stainless Steel

• Enclosure: NEMA 4X / IP66 (aluminum, epoxy-coated)

  

1.2 Key Features & Benefits

• High Accuracy & Stability: ±0.1% of span typical performance

• Wide Pressure Range: Adjustable from 7.5 to 3000 PSI

• Rugged Construction: 316L SS sensor for corrosion resistance

• Loop-Powered Design: Simplified wiring, low power consumption

• Compact, Lightweight: Direct process mounting

• Industrial Certifications: CE, UL, RoHS compliant

• Wide Temp Range: -40°C to +85°C operating temperature

1.3 Typical Applications

• Semiconductor manufacturing & cleanroom pressure control

• Petrochemical, chemical, and pharmaceutical processing

• Oil & gas production, refining, and pipeline monitoring

• Power generation (boilers, turbines, compressors)

• Water treatment, HVAC, and industrial automation

2. Safety & Installation Preparations

2.1 Safety Warnings

• WARNING: Risk of explosion if installed in hazardous areas. Use only in approved classified locations.

• WARNING: Disconnect power before wiring, installation, or maintenance.

• WARNING: Ensure process pressure is relieved before removing the transmitter.

• CAUTION: Do not exceed maximum pressure or temperature ratings.

• CAUTION: Use proper tools and follow local electrical codes (NEC, IEC, etc.).

2.2 Unpacking & Inspection

1. Remove the transmitter from packaging.

2. Inspect for physical damage (dents, cracks, loose parts).

3. Verify model number: 841GX-CI1.

4. Confirm included accessories:

• Mounting hardware

• 1/2 NPT conduit plug

• Product label & calibration sheet

2.3 Tools Required

• 13/16-inch (or 21 mm) wrench

• Screwdriver (flat / Phillips)

• Pressure calibrator (for setup)

• Multimeter (4–20 mA measurement)

• Proper grounding cables

3. Mechanical Installation

3.1 Mounting Location

• Mount in a location with minimal vibration and temperature extremes.

• Protect from direct sunlight, rain, and corrosive fumes.

• Ensure easy access for wiring, calibration, and maintenance.

3.2 Process Connection

• Process Connection: 1/2–14 NPT male (standard)

• Apply thread sealant (non-hardening) to male threads.

• Tighten securely using a wrench on the hex base (not the electronics housing).

• Ensure proper alignment to avoid mechanical stress.

3.3 Conduit & Wiring Entry

• Use 1/2 NPT conduit connections.

• Seal conduits to maintain NEMA 4X / IP66 protection.

• Route cables away from high-voltage power lines to avoid EMI/RFI interference.

4. Electrical Installation

4.1 Wiring Diagram (2-Wire Loop)

1. Power Supply (+) → Transmitter Terminal (+)

2. Transmitter Terminal (–) → Controller/PLC Input (–)

3. Ensure a clean instrument ground for the shield.

4. Use twisted-pair, shielded cable (22–18 AWG).

4.2 Terminal Connections

• Open the electronics housing cover.

• Identify terminals: + (positive), – (negative).

• Securely fasten wires; avoid loose connections.

• Replace cover and tighten screws to maintain environmental seal.

4.3 Grounding

• Connect cable shield to a single-point instrumentation ground.

• Do not ground at multiple points (prevents ground loops).

5. Commissioning & Calibration

5.1 Power-Up

• Apply 12.5–36 V DC to the loop.

• After ~5 seconds, the transmitter outputs 4 mA (zero pressure).

5.2 Zero & Span Calibration

1. Zero Calibration (0%):

• Apply zero pressure to the sensor.

• Adjust zero potentiometer until output = 4.00 mA.

2. Span Calibration (100%):

• Apply full-scale pressure (e.g., 1000 PSI).

• Adjust span potentiometer until output = 20.00 mA.

3. Repeat steps 1–2 for best accuracy.

5.3 Verification

• Test at 0%, 50%, 100% of range.

• Confirm linearity and error within ±0.1% of span.

6. Operation & Maintenance

6.1 Normal Operation

• The transmitter operates continuously once calibrated.

• Output signal: 4 mA = 0% pressure, 20 mA = 100% full scale.

• No routine adjustments required under stable conditions.

6.2 Routine Maintenance

• Inspection: Every 3–6 months

• Check for leaks, corrosion, or physical damage.

• Tighten conduit and housing seals.

• Cleaning: Wipe housing with a soft, dry cloth.

• Calibration Check: Annually or after process disturbance.

7. Specifications

7.1 Performance

• Accuracy: ±0.1% of span (typical)

• Stability: ±0.1% per year

• Response Time: < 100 ms

• Temperature Effect: ±0.02% / °F

7.2 Electrical

• Supply Voltage: 12.5–36 V DC

• Output: 4–20 mA DC (2-wire)

• Reverse Polarity Protection: Yes

7.3 Environmental

• Operating Temp: -40°C to +85°C (-40°F to +185°F)

• Storage Temp: -50°C to +121°C (-58°F to +250°F)

• Humidity: 0–100% RH

• Enclosure Rating: NEMA 4X / IP66

7.4 Physical

• Wetted Material: 316L Stainless Steel

• Process Connection: 1/2–14 NPT male

• Weight: ~1.0 kg (2.2 lbs)

8. Warranty & Support

8.1 Warranty

• Warranty Period: 12 months from delivery.

• Covers defects in materials and workmanship under proper use.

• Exclusions: Damage from misuse, improper installation, overpressure, or unauthorized repair.

8.2 Support Contact

Easy Semiconductor Technology (Hong Kong) Limited

• Address: Hong Kong, China

• Support Email: support@hongkongeasy.com

• Website: www.hongkongeasy.com