Vapor Quality Sensor - ATEX

Category: HBX-ST for DX and Overfeed systems - ATEX/IECEx certifided

With a vapor quality sensor integrated into a standard strainer house you are ensured safe functionality of the sensor and easy installation. The butt-welded connection makes it easy to weld with same size of piping.

Please be aware that the flow direction of the vapor quality sensor is opposite of the flow direction when used as a strainer. If installed with wrong flow direction functionality will NOT be correct.

Besides the benefit of easy installation this solution makes it easy to dismantle the lid with the sensor conductor and clean it if necessary.

The sensor integrated into standard strainer housing is available in both carbon steel DN20 to DN300 and stainless steel DN20 to DN65. Ask for availability if size outside of this range is requested.

Intrinsically Safe design:

Intrinsically Safe (IS) sensors are designed and wired to work on such a low current and voltage that it cannot possibly ignite flammable material. By limiting the energy available within the defined hazardous area, electrical equipment can operate safely even amid hazardous mixtures of gasses.

Product selection guide

To find the right part number to purchase please use our selection guide in the shop (link below), product overview under "ordering code" or send our Product Manager Henrik Kudsk a system description and he will guide you to the right part number. Please use the "Product Specification Form" (find it under the "downloads" tab on this product page) and e-mail it to   


Product features

Measures the volumetric concentration of gas in a gas/liquid mixture
Balanced evaporator control to achieve semi-flooded operation with high heat transfer
Can be used to optimize and control both DX systems and overfeed systems
Instant measurement and analog output
Can be used for all common refrigerants


Flooded system:


Optimum efficiency at all loads is obtain by measuring the Vapor Quality in the outlet of the evaporator and use the signal to change the height of the driving head as shown, lower level will minimize the liquid amount  in the evaporator and secure balanced and dynamic evaporation  during part load and thus optimum heat transfer.

The HBX-OVC-ST Vapor Quality control signal (cable out, 4-20mA) is connected to DI 3 (pin 3) on the HBSLC liquid level sensor and used to change the desired set value for the liquid level in the recirculation vessel/separator.






Technical data:


Connection Diagram

Diagram sensor




 Danfoss Strainer DN20 DN65 profiltegninger WEB


Tabel Dimensioner DN20 DN65





Danfoss Strainer DN65 DN200 profiltegninger WEB

 Tabel Dimensioner DN80 DN200

Danfoss Strainer DN250 DN300 profiltegning WEB

Tabel Dimensioner DN250 DN300

Strainer small

In the sizes DN20-DN40 the strainer is extended with a 100 mm tube.

Power supply
Voltage12-28 V DC two wire
Max. current consumption Max 20 mA
Plug connectionsM12, 5 pins - DIN 0627
Signal output 4....20 mA (AO)
IECEx classificationEx ia IIC T1…T6 Ga
Device category1G for Zone 0 & 1
Type of protectionia
Gas resp. gas groupIIC
Temperature classT1….T6
Mechanical specifications
Ambient temperature-40...+50°C/+70°C
Max pressure100 bar
Protection degreeIP65
VibrationsIEC 68-2-6 (4g)
Environmental conditions
Material liquid partsAISI 304 / PTFE
Material electronic partsNylon 6 (PA)
Outsite dimensions210 x 51 x 72 mm
Weight500 g
Ex area
EMCEN 61000

Ordering code

Pipe diameterDesignMaterialATEX/IECEx approvalOrdering code
DN20OVCCarbon SteelZone 1HBX-CR-ST-D20-Z1
DN25OVCCarbon steel Zone 1HBX-CR-ST-D25-Z1
DN32OVCCarbon steel Zone 1HBX-CR-ST-D32-Z1
DN40OVCCarbon steel Zone 1HBX-CR-ST-D40-Z1
DN50OVCCarbon steel Zone 1HBX-CR-ST-D50-Z1
DN65OVCCarbon steel Zone 1HBX-CR-ST-D65-Z1
DN80OVCCarbon steel Zone 1HBX-CR-ST-D80-Z1
DN100OVCCarbon steel Zone 1HBX-CR-ST-D100-Z1
DN125OVCCarbon steel Zone 1HBX-CR-ST-D125-Z1
DN150OVCCarbon steel Zone 1HBX-CR-ST-D150-Z1
DN200OVCCarbon steel Zone 1HBX-CR-ST-D200-Z1
DN250OVCCarbon steel Zone 1HBX-CR-ST-D250-Z1
DN300OVCCarbon steel Zone 1HBX-CR-ST-D300-Z1
DN20OVCStainless Steel Zone 1HBX-CR-ST-D20-S -Z1
DN25OVCStainless Steel Zone 1HBX-CR-ST-D25-S-Z1
DN32OVCStainless Steel Zone 1HBX-CR-ST-D32-S-Z1
DN40OVCStainless Steel Zone 1HBX-CR-ST-D40-S-Z1
DN50OVCStainless Steel Zone 1HBX-CR-ST-D50-S-Z1
DN65OVCStainless Steel Zone 1HBX-CR-ST-D65-S-Z1
DN80OVCStainless Steel Zone 1HBX-CR-ST-D80-S-Z1
DN100OVCStainless Steel Zone 1HBX-CR-ST-D100-S-Z1
DN20DXCarbon Steel Zone 0HBX-CR-ST-D20-Z0
DN25DXCarbon steel Zone 0HBX-CR-ST-D25-Z0
DN32DXCarbon steel Zone 0HBX-CR-ST-D32-Z0
DN40DXCarbon steel Zone 0HBX-CR-ST-D40-Z0
DN50DXCarbon steel Zone 0HBX-CR-ST-D50-Z0
DN65DXCarbon steel Zone 0HBX-CR-ST-D65-Z0
DN80DXCarbon steel Zone 0HBX-CR-ST-D80-Z0
DN100DXCarbon steel Zone 0HBX-CR-ST-D100-Z0
DN125DXCarbon steel Zone 0HBX-CR-ST-D125-Z0
DN150DXCarbon steel Zone 0HBX-CR-ST-D150-Z0
DN200DXCarbon steel Zone 0HBX-CR-ST-D200-Z0
DN250DXCarbon steel Zone 0HBX-CR-ST-D250-Z0
DN300DXCarbon steel Zone 0HBX-CR-ST-D300-Z0
DN20DXStainless Steel Zone 0HBX-CR-ST-D20-S-Z0
DN25DXStainless Steel Zone 0HBX-CR-ST-D25-S-Z0
DN32DXStainless Steel Zone 0HBX-CR-ST-D32-S-Z0
DN40DXStainless Steel Zone 0HBX-CR-ST-D40-S-Z0
DN50DXStainless Steel Zone 0HBX-CR-ST-D50-S-Z0
DN65DXStainless Steel Zone 0HBX-CR-ST-D65-S-Z0
DN80DXStainless Steel Zone 0HBX-CR-ST-D80-S-Z0
DN100DXStainless Steel Zone 0HBX-CR-ST-D100-S-Z0








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