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zelsius® C5-ISF - Thermal energy meter with single-jet flow sensor (ISF)

The thermal energy meter (also called heat or cold meter) zelsius® C5-ISF with single-jet flow sensor combines efficiency with compact design, highest precision and most advanced communication interfaces for M-Bus, wireless M-Bus or LoRa®.

Specially designed for sub-metering applications, it is very well prepared to be used in all real estate with central heat supply:

  • Industrial and business buildings
  • Apartment buildings and residential complexes
  • Multi-family buildings

The advantages of zelsius® C5-ISF can be observed even by the installation. With its compact design it is suitable for nearly any installation situation.
The combi version with removable calculator allows installation even in the smallest distribution boxes. Zelsius® C5-ISF can be easily operated via one single button. The application-oriented display offers an optimum of readability and practical demonstration of relevant operating conditions.
Zelsius® C5-ISF is a threaded meter, equipped with a rugged single-jet flow sensor (ISF) with reaction-free electronic impeller detection, available for new installations as well as for simple calibration replacement in all common sizes.

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Product images

Heat Meter/ Cooling Meter zelsius® C5 ISF with Single-Jet Flow-sensor
Heat Meter/ Cooling Meter zelsius® C5 ISF with Single-Jet Flow-sensor


zelsius® C5-ISF - Thermal energy meter with single-jet flow sensor (ISF)

Performance characteristics in overview

  • Available as heat or combined heat/ cooling energy meter as well as glycol meter
  • Lowest design height
  • Optionally available with M-Bus, wireless M-Bus or LoRa® as well with 3 programmable inputs / outputs
  • OMS certification for BSI-compliant smart meter gateway connection
  • For horizontal and vertical installation position
  • Stores monthly readings during the whole running time
  • Extensive maximal value storage of thermal output, flow rate and other parameters
  • No straight inlet or outlet sections required

Product options

Measuring Principle
  • Single-Jet Meters
  • Electronic
Housing Material
  • Brass
Nominal Flow qp (Heat Meters)
  • qp = 0,6
  • qp = 1,5
  • qp = 2,5
Communication Technologies
  • Combined M-Bus and pulse module
  • Radio via LoRaWAN®
  • Radio via wireless M-Bus
  • optional 3 pulse inputs or outputs
  • Optical interface
  • M-Bus
  • Heating circuit up to 90 °C
Specified Units on Display
  • Cubic Meters (m³)
  • Degrees Celsius (°C)
  • Gigajoule (GJ)
  • Kilowatt hours (kWh)
  • Megawatt hours (MWh)


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