IR29 DB Transmitter

With Modbus and display for flammable gases in Ex zones

If flammable gases and vapors need to be monitored in Ex zones, the IR29 DB transmitter is a reliable and robust solution. It transmits measured values and status notifications via Modbus protocol on an RS-485 interface. The LC display indicates the current measured values. Gases are monitored either on site by diffusion or by pressureless gas supply using a flow adapter. In combination with one of GfG's reliable controllers, it can be installed in new gas detection systems or retrofitted into existing ones.

The IR29 DB uses non-dispersive infrared (NDIR) sensor technology to detect combustible gases and vapors. Our patented 4-beam and 4-wavelength technology with gold-plated mirror optics, which do not require any beam splitters, is used to ensure selective measurement results without false alarms.The installed infrared sensors detect up to three gases simultaneously and also enable measurements above the lower explosion limit (LEL). They do not require oxygen and are not susceptible to sensor poisons. The long-life sensors make the IR29 DB a permanently reliable solution for detecting a wide range of combustible gases and vapors in the 0 to 100 % LEL measuring range. Its automatic temperature compensation and the linearization of the measurement signals ensure high measurement accuracy.

Communication and service
The IR29 DB transmits signals via the digital RS-485 interface (Modbus). Two status LEDs are used to indicate its operation status. The LC display indicates the current measured gas concentration. Depending on the location of the installation, you might also be interested in the rotating version. Service and adjustments can be carried out on site using the optional RC2 remote control or the RC3 IR remote control (one-man adjustment). The IR29 DB's self-monitoring functions increases device safety between maintenance intervals. The transmitter automatically records measured values and incidents in an internal ring buffer. Test gases for function tests and adjustments can be inserted via a calibration adapter.

Safety and instrument protection
The IR29 DB is ATEX certified for use in Ex zone 1. It complies with the increased safety "e" and encapsulation "m" standards. The housing made of V4A stainless steel and poly-carbonate is protected against the ingress of dust and water (protection class: IP67). Accessories include a guard plate and dust filter.


Key features at a glance:

General information:

  • Measuring principle: infrared (IR)
  • For combustible gases and vapors
  • Not susceptible to sensor poisons
  • Expected sensor lifetime: 6 years
  • Color display (optional: rotating display)
  • Signal transmission: RS-485 (Modbus)
  • Protection class: IP67 (with rotating display: IP40)
  • Integrated data logger

Approvals / Certifications:

  • ATEX certification: II 2G Ex eb mb ib [ib] IIC T4 Gb

Optionally available:

  • Pressure and humidity sensors, ex-proof control unit RC2, impact protection, flow adapter, calibration adapter, protection plate, dust filter, weatherproof housing, flow adapter

Detectable gases

LEL combustible gases
C2H2 Acetylene
C2H4 Ethylene
C2H6O Ethanol
C3H8 Propane
C3H8O n-Propanol
C4H10 n-Butane
CH4 Methane
Other gases on request.


Extensions and accessories

Weatherproof housing

Weatherproof housing for various transmitters
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Test gases

Find an overview of our test gases here
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Accessories IR29 DB

Find the complete list of accessories for the IR29 DB here
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