Measurement of thermal power in the chilled-water system


Our application case is situated in the cooling power plant that supplies chilled water to the Valmy district of La Défense (Nanterre). The power plant, built in 1995, is equipped with two 3MW generators and a 30MW ice storage room.


The flow meter is installed at the outflow from the power plant on a 450mm diameter stainless steel pipe. The flow is around 850m3/hr. A temperature probe is installed at the power plant’s inflow and the other at the outflow. Two current outputs deliver the flow and thermal power values.


Uf 322 converter SE 1515 clamp-on probes
Convertisseur Uf 322 Sonde externe SE 1515
This is a fixed converter that is no longer sold by Ultraflux. It delivers a current output and is equipped with a temperature module.
The recent devices Uf 811, Uf 821 and Uf 831 could also be used for the type of application described.
They are high-temperature probes capable of withstanding temperatures of up to 180°C.

The following are also supplied:

  • 10m of Twinax cabling,
  • Two PT100 temperature probes,
  • One clamp-on module with a second current output.


The setpoint temperature of the water to be provided is, according to the terms of the contract, set between +4°C and +5°C.


  • All the flow measurement and temperature probes are installed on the outside of the pipe, which means they can be quickly and easily installed without cutting into the pipe and therefore without interrupting the circulation of water.
  • No maintenance is required.