Description
Fischer DE44 Ex – Dual Sensor DP Transmitter
– Zone 2, 22
Explosion proof, dual independent pressure sensor for differential pressure, positive, negative, vacuum monitoring for air, clean gases
Make: Fischer Messtechnik (Germany)
Model: DE44…R (for gas explosion proof Zone 2), DE44…S (for dust explosion proof Zone 22)
Fischer DE44 is uniquely designed, state-of-art pressure instrument with inbuilt dual pressure sensor to monitor and compare two independent differential pressures. It comes in explosion proof version as DE44…R (for zone 2, gas explosion proof) and DE44…S (for Zone 22, dust explosion proof).
- DE44..R: Suitable for use as electrical equipment for use in explosion – hazardous area (flammable gas) Zone Declaration per Directive 94/9/EC (ATEX)
Ex II3G EEx nA IIC T4 - DE44..S: Suitable for use as electrical equipment for use in explosion – hazardous area (flammable dust) Zone 22
Declaration per Directive 94/9/EC (ATEX)
Ex II3D IP65 T125° C
DE44 is multi-function pressure instrument which combines digital readout, dual limit detection relays and transmitter output.
It can measure positive gauge, negative or differential pressure of two independent gas or air pressure sources.

Working Principle:
Fischer DE44 Ex is based on dual piezo-resistive sensing element. The pressure is measured directly by piezo-resistive resistance bridge that is formed on surface of an integral silicon diaphragm in each sensor chamber.
The change in pressure results in change of resistance that is converted to varying voltage and which in turn convert to digital signals. The instrument’s internal micro-controller transfers measured value to LED Display, control two limit detection contacts/ relays, and transmit measured values through analog conversion stage as voltage or current signal.
An optional output signal can be slew limited, spreaded, inverted and transformed non-linearly by means of table function.
Key Features:
- Two independent differential pressure sensors
- Robust design, over-pressure protected
- Selectable pressure unit
- Signal output with possibility of spreading and inverting characteristic curve with any offset (optional)
- Characteristic conversion of output via 3….30 entries tablets)
- Fully programmable via PC based EU03 module
- Large LED Display
Key Specifications:
- Two independent differential pressure sensor.
- Measuring range (of each sensor): 0 ~ 4.0 mbar up to 0 ~ 100 mbar; ± 2.5 mbar to ± 60.0 mbar
- Maximum static operating pressure: 50 mbar to 500 mbar
- Maximum safe pressure: 150 mbar to 1500 mbar
- Straight line deviation error (max): 1.0% full scale
- Pressure connection: G 1/8 female threads with optional cutting ring fittings for 6 or 8 mm tube
- Operating ambient & media temperature: -10° C to +70° C
- Protection class: IP65 per DIN EN 60529
- Electrical output: 4-20mA or 0-10V, 3 – wire
- Power supply: 24 V DC/ AC
- Switching contacts: 2 sets of programmable voltage free contacts: NO or NC
- Display: 3 1/2 digit LED
- Electrical connections: two round shell multi-pin connector sockets (M12, male)
- Material, housing: Polyamide PA 6.6
- Materials, media contact: Silicon, PVC, aluminum, brass
Application areas:
- Roll band filter monitoring
- Vacuum system monitoring
- Chimney draught measurement
- Flow and control pressure monitoring
- Surface coating system
- Pump monitoring and control
- Compressor monitoring and control
Industrial areas:
- Air conditioning and ventilation systems
- Auditorium, office, conference rooms
- HVAC and ventilation application
- Environment monitoring
- Clean room and laboratory rooms