Honeywell 3000MkII and MkIII Gas Transmitters
Starting at $735.00

Not in stock. Usually ships in 2-3 weeks [?]

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  • Proven Surecell™ electrochemical sensing technology, ideal for hot and humid environments
  • 2-wire loop powered
  • Long-life sensing elements
  • Patented ‘Reflex’ sensing element verification diagnostics
  • Plug and play factory configured sensors
  • IS sensor connection permits hot swap, reducing downtime
  • 4-20mA output
  • IP66 (EN 60529), NEMA 4X rated construction
  • User programmable calibration frequency
  • Integral fault diagnostic software
  • Sensor recognition feature auto configures transmitter
  • Integral surface mounting lugs and optional brackets provide numerous mounting options
  • Menu/icon driven calibration procedure
  • Approvals:
    • MkII: suitable for use in Zone 1, 2, 21 or 22 hazardous areas and North American Class I and II Division 1 or 2 areas
    • MkIII: suitable for use in Zone 0, 1, 2, 20, 21 or 22 applications

What's in the Box

  • Blanking plug
  • Hex wrench set
  • Weatherproof cap
  • Operating magnet
  • Calibration and test certificate
  • Instruction manual
  • Gas specific sensors are NOT included and must be ordered separately

The Honeywell 3000 MkII and MkIII range of gas transmitters provide comprehensive monitoring of toxic and oxygen gas hazards in potentially explosive atmospheres. Suitable for mounting both indoors and out, they are available in two versions and offer excellent versatility. The MkII is contained in a flameproof housing, has an intrinsically safe sensor connection and is for use in predominantly Zone 1 applications. However with the use of the optional remote mounting kit the sensor of the MkII can be mounted in a Zone 0 environment. The MkIII is for use with a separate suitable IS barrier allowing the complete transmitter to be used in Zone 0 applications.

These low powered gas detectors all feature a loop powered 4-20 mA connection, making them ideal for both new and retrofit installations. Users can configure the detector through the use of the easy to read LCD and intuitive interface while fault diagnostic software and a programmable calibration period greatly simplify maintenance procedures.

The intrinsically safe smart sensors (gas sensors are not included and must be purchased separately) are supplied pre-configured and can be ‘hot swapped' without having to remove power to the detector, saving time and money during commissioning and routine servicing. A remote sensor mounting kit is available that allows the sensor to be mounted up to 15m (50ft) from the transmitter, making it ideal for operation in areas that are difficult to access.

The Honeywell 3000 MkII and MkIII range of gas transmitters are supplied with all necessary accessories for easy installation. The detector can be wall mounted using the integral mounting lugs or pipe mounted (horizontal or vertical) using the optional pipe mounting kit. Electrical installation is made using the 2 x M20 cable entries (ATEX/IECEx version) or 2 x 3/4"NPT conduit entries (UL/c-UL versions). A suitable blanking plug is also supplied to seal any unused entries. A weatherproof cap is included for use in the harshest outdoor conditions.

Required Components

These additional components are required for the operation of your product. We strongly advise you to purchase these components unless you already own them or own a suitable alternative.

Honeywell Smart Sensor Cartridges
Electrochemical oxygen and toxic gas sensors for use with Honeywell gas transmitters


Honeywell XNX Toxic Calibration Kit
Includes accessories need to perform calibrations on toxic gas sensors (does not include calibration gas)
Honeywell S3KCAL Calibration Cap
Calibration cap for use with EC Sensors

Mounting Bracket

Honeywell Duct Mounting Kit
Duct mount kit for Honeywell gas transmitters
Honeywell Remote Sensor Mounting Kit
ATEX/UL/cUL approved enclosure with sensor socket, 50ft of digital cable & glands, transmitter cable plug, & mounting screws


Honeywell S3K Sensor Cells
Replacement electrochemical oxygen and toxic sensor cells for Honeywell gas transmitters
In Stock


Please consider these optional accessories.

Honeywell SPXCDCC Collecting Cone
Collecting cone for use with lighter than air gases (for carbon monoxide (CO) and hydrogen (H2) only)
Honeywell SPXCDSDP Sunshade
Honeywell SPXCDSDP Sunshade/Deluge protection
Honeywell Calibration Gas
Combustible & toxic gases for Honeywell calibration kits