CIAT V300 - Characteristics of the Sensors Used by the V300; Measuring the Water Temperature

NA 12.54 D EN - 12
The sensor can be chosen using setting P11 (=0: return air sensor; =1: indoor environment sensor).
If the selected sensor is faulty, the other sensor immediately takes over. A symbol is displayed on the screen and the fault can
also be looked up in the variable of diagnostic d07.
The sensor measurement can be corrected by means of parameter P12 (return sensor) or P13 (room sensor).
11 - CHARACTERISTICS OF THE SENSORS USED BY THE V300
All the sensors used by the V300 (return, changeover) have the same specifications
Temperature °C 5 10 15 20 25 30 35
Resistance Ohms 22 050 17 960 14 690 12 090 10 000 8 313 6 940
12 - MEASURING THE WATER TEMPERATURE
Two-tube heating/cooling comfort units may be fitted with a water temperature sensor (or changeover sensor). It must be
positioned by the installer upline of the 4-way valve (water network end). It is fixed to the pipe using electrician's clips and located
underneath the pipe's thermal insulation.
Position and use of the changeover sensor
Sensor
Valve motor
3-way valve with
built-in bypass
(often called a
4-way valve)
Insulation
Water inlet pipe
Clamp
Sensor adapter
Sensor
20 cm
min.
150 cm
150 cm
- Changeover operating algorithm:
• If the changeover sensor measures a water temperature greater than 7°C (P48 adjustable) at room temperature, the water is
deemed to be hot.
• If the changeover sensor measures a water temperature lower than 4°C (P49 adjustable) at room temperature, the water is
deemed to be cold.
• If the changeover sensor measures water temperature between these two values, the water is deemed neutral.
- Changeover operation with water at neutral temperature:
In this scenario, and if the controller requirement is confirmed, the V300 launches a test cycle on the valve so as to check the
network's available water temperature (valve 100% opened to authorise water circulation in the terminal unit coil).
- If this temperature does not vary, the V300 keeps the same status
- If this temperature varies and returns to the conditions described above, the V300 re-authorises its control cycle.