Cooling Meter Application - INTEGRA Metering CALEC energy master Installation And Operating Instructions Manual

9.1.3

Cooling meter application

The following characteristics differentiate the cooling meter application from the heat meter appli-
cation:
• The supply temperature is lower than the return temperature, i.e. Tsupply = Tc, Treturn = Th.
• The temperature difference is in the range of 1 ... 15 K. This means that, for the same energy
consumption, the flow rate is markedly higher than in heating applications.
• There is a risk of water condensing on the flow sensor, i.e. the sensor should be adequately
protected against ingress of water (e.g. IP 67).
• If the supply temperature is < approx. 3 °C, pure water cannot be used as the heat transfer me-
dium. The device is available with a selection of standard commercial heat transfer liquids for
this application.
With cooling meters, it is preferable to mount the flow sensor on the hot side in order to reduce
thermal effects. The installation side should be set correspondingly. In terms of sensor location,
this corresponds to installation in the return flow pipe.
Furthermore, suitable temperature sensors must be used. This can affect the test points, the mois-
ture resistance of the sensors and the cable sheath and the use of heat transfer barriers.
Required measuring signals: Supply and return temperature, flow rate signal.
Mod.-Typ Mod.-Typ
Mod.-Nr. Mod.-Nr.
Sign.-Typ Sign.-Typ
Sign.-Nr. Sign.-Nr.
The device provides the following meter readings:
E: Cumulative energy
V: Cumulative volume
M: Cumulative mass
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CALEC energy master installation and operating instructions
Supply Supply Input Input
3... 6 3... 6 2 2
Input Input
2 2 1 1
230 VAC 230 VAC Qv Qv
CPU 2 x Pt100 CPU 2 x Pt100
1 1
Pt100-Input Pt100-Input
2 2 1 1
Th Th
Tc Tc
E E
V V
M M
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