DE80 Differential Pressure Transmitter | Fischer

Key Features: DE80 Differential Pressure Transmitter for HVAC and Filter Monitoring | Fischer

The Fischer DE80 is a digital differential pressure transmitter designed to measure positive pressure, negative pressure and differential pressure in air and neutral gases. Typical applications include HVAC systems, ventilation, air-conditioning, filter monitoring, cleanrooms, building automation and indirect airflow measurement.

The transmitter uses a piezoresistive sensing element with a silicon diaphragm. The pressure difference applied to the positive and negative ports deflects the diaphragm, and the integrated electronics convert this change into an analogue output signal or a digital value via RS485 Modbus RTU, depending on the selected version.

The DE80 range is available in 2-wire and 3-wire versions, with or without a graphical display, and can optionally include an adjustable changeover contact. Configurable measuring ranges, zero-point correction and square-root extraction make the transmitter suitable for a wide variety of differential-pressure and airflow-control applications.

Main Specifications: Fischer DE80 Differential Pressure Transmitter

Configuration and Diagnostic Functions of the Fischer DE80

• Selectable measuring ranges: each basic sensor range can be configured for different measurement spans.
• Zero-point adjustment: integrated button for offset correction during commissioning.
• Square-root extraction: linearises the relationship between differential pressure and airflow when used with a primary flow element.
• Signal damping: helps stabilise readings in applications with fluctuating pressure.
• Optional switching contact: enables filter alarms or pressure-limit signalling without an additional controller.
• Optional Modbus RTU: simplifies integration with PLC, BMS, SCADA and building-automation networks.

Industrial Applications: Differential Pressure Measurement with the DE80

Filter Monitoring in HVAC Systems

The DE80 measures the pressure drop across a filter to detect progressive contamination. The measured value can be used to generate an alarm, schedule maintenance or control fans and extraction systems.

Cleanrooms and Laboratories

Positive and negative pressure measurement makes it possible to monitor pressure cascades between rooms, airlocks and classified areas. The transmitter can be integrated into a BMS or SCADA system using an analogue signal or Modbus RTU communication.

Fan and Variable-Frequency Drive Control

The DE80 output can be used to regulate fan speed through a variable-frequency drive, maintaining constant duct pressure or airflow while improving the energy efficiency of the installation.

Airflow Measurement

When combined with Pitot tubes, orifice plates, flow grids or other primary elements, the transmitter measures the differential pressure generated by the airflow. Its square-root function provides an output proportional to flow.

Building Automation and Technical Facilities

Its compact housing, multiple output options and RS485 communication make the DE80 suitable for heating, ventilation, air-conditioning, extraction, filtration and energy-management systems in industrial and commercial buildings.

Advantages of the Fischer DE80 Transmitter

• Measures differential pressure, positive pressure and negative pressure with one device.
• Available with analogue output, 2-wire current loop or Modbus RTU.
• Optional graphical display and switching contact.
• Configurable ranges reduce the number of models required.
• Simple zero-point correction during commissioning.
• Square-root function for airflow measurement applications.
• Compact, robust, silicone-free and maintenance-free design.
• Suitable for PLC, SCADA, BMS and building-automation integration.

How to Select the Correct Fischer DE80

The following application data should be defined before selecting the DE80 differential pressure transmitter:

• Minimum and maximum differential-pressure range.
• Unidirectional or bidirectional measurement.
• Required output: 4–20 mA, 0–10 V, 2–10 V or Modbus RTU.
• Available supply voltage and preference for 2-wire or 3-wire connection.
• Requirement for local display.
• Requirement for a switching or alarm contact.
• Application: filter, cleanroom, fan, airflow or pressure control.
• Pressure-tube diameter and length.
• Ambient temperature and installation conditions.

Fischer Distributor for Differential Pressure Solutions

Garma Electrónica supplies and provides technical support for Fischer differential pressure transmitters used in HVAC systems, industrial filtration, cleanrooms, building automation and process control.

We can help select the correct measuring range, electrical output and DE80 configuration, as well as assess alternative Fischer models when the application requires higher accuracy, additional switching contacts, IO-Link, ATEX approval or other advanced functions.

Contact us with your application requirements so that we can define the correct configuration.