TQ ENVIRONMENTAL GD129NI Single Point Infra-Red Gas Detector

What is it?
The TQ Environmental GD129NI is a single-point infrared gas detector that is pre-calibrated and designed for reliable detection of combustible hydrocarbons or CO₂ in hazardous explosive environments. The detector is suitable for continuous monitoring of gas concentrations and can be used in a variety of industrial applications where safety and accuracy are essential. Thanks to advanced SMT components, the GD129NI is robust and reliable, with low power consumption and a wide temperature range.

How does it work?
The GD129NI operates based on the infrared absorption principle and features built-in reliability checks for optimal performance. The system requires no separate programmer and provides a standard 4-20 mA output signal. The detector contains no heating elements, mirrors, or optical parts that can become contaminated, ensuring low-maintenance operation. The control unit can optionally be mounted separately from the sensor, offering flexibility during installation.

What problems does it solve?
The GD129NI provides a reliable and straightforward solution for continuous monitoring of gas concentrations in potentially explosive environments. By combining robustness with advanced technology, it minimizes the risk of malfunctions and contributes to the safety of personnel and installations. This makes it an ideal choice for situations where accurate gas detection under harsh conditions is required.

Construction
Sensor housing: 316 stainless steel with hydrophobic protective coating
Protection guard: Stainless steel guard
Junction box: Copper-free aluminum with polyester paint finish
Ingress protection: IP55
Cable entry: M20
Weight: approx. 2.1 kg
Dimensions: 130 mm (W) x 230 mm (H) x 120 mm (D)

Temperature and Humidity Range
Temperature range: -30 °C to +60 °C
Humidity: 0 to 99% relative humidity (non-condensing)

Shock and Vibration
Shock: Half sine, 15 g, 20 ms duration on all axes
Vibration: 3–10 Hz, displacement 0.5 mm
Resistance: 10–50 Hz, 2 m/s²

Outputs
4–20 mA output, source type, max 600 Ohm load

Power Supply
Operating voltage: 24 VDC (11–30 VDC)
Current consumption: 75 mA at 24 VDC (2.1 Watts)

Accuracy and Repeatability
Accuracy: ±2% full scale (linearized)
Repeatability: ±1% full scale

Gas Types and Ranges
HC (hydrocarbon) version: 0–100% LEL standard, optional 0–100% volume
Standard monitored gases: methane, propane, butane, hexane, ethylene, pentane, ethane, toluene
CO₂ version: 10,000 ppm & 50,000 ppm (0–2% v/v, 0–5% v/v)

Response Time
<10 seconds to T50
<20 seconds to T90 (for CH₄ and CO₂)

Self-Test
Continuous built-in self-test

Settings
Non-intrusive adjustments
Calibrated for up to 2 years with automatic zero and calibration facility

Lifetime and Warranty
Expected lifetime: >5 years
Warranty: 12 months

Certification
EEx d IIC T6 (Ta = -20 to +55 °C)
SIRA 01 ATEX IIII

GD129NI SINGLE POINT INFRA-RED GAS DETECTOR

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