CIAT V3000 KNX, Руководство по управлению

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● Parameter P24
Diagnostics d08, d09
The V3000 offers the possibility of controlling the air temperature via a return sensor or an indoor environment sensor (P24).
If you can choose between the two, it is preferable to opt for the indoor environment sensor, since it provides a better picture of
the room temperature.
The indoor environment sensor is situated inside the user terminal unit. When it is used, particular care must be taken in choosing
the location of the user terminal in the room (do not expose it to sunlight, or place it on top of a device giving off heat - put it on
an inside partition).
The end of the wiring conduit must be heat insulated.
20 cm
mini
150 cm
~ 150 cm
The choice of sensor is made using parameter P24 (=0: return 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 d22.
In case of doubt about the origin of the displayed temperature value, the value measured by the return sensor can be read in d09.
The value measured by the indoor environment sensor can be read in d08. If the sensor is absent, the value displayed is equal to 0.0°C.
The sensor measurement can be corrected by means of parameter P25 (return sensor) or P26 (indoor environment sensor).
6 - AIR TEMPERATURE MEASUREMENT
●
Parameters P27, P28
Diagnostic d11, d12
The 2-pipe hot/cold fan-coil units may be fitted with a water temperature sensor (or changeover sensor). It must be positioned
using a conduit clip by the installer upline of the four-way valve (water piping end). It is fastened to the pipe by means of
electrician's clamps.
Position and use of the changeover sensor
Water inlet
pipe
Insulation
Clamp
Sensor adapter
Sensor
Valve motor
3-way valve with
built-in bypass
(often called a
4-way valve)
Sensor
● Changeover operating algorithm:
- If the changeover sensor measures water temperature greater than 7°C (adjustable in P27) at ambient temperature, the
water is deemed to be hot.
- If the changeover sensor measures water temperature less than 4°C (adjustable in P28) at ambient temperature, the water
is deemed to be cold.
- If the changeover sensor measures water temperature between these 2 values, the water is deemed neutral.
● Changeover operation with water at neutral temperature:
In this scenario, and when there is an established need from the controller, the V3000 launches a test cycle on the valve every 45
mins 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 V3000 keeps the same status
- If this temperature varies and returns to the conditions described above, the V3000 re-authorises its control cycle
Important : the changeover sensor measures the surface temperature of the piping. There is an obvious difference between the
actual water temperature and the surface temperature. The water speed will therefore be selected so as to guarantee changeover
switching.
- For P31 = 1, if nothing is connected between terminals S2 and C, the controller deduces that the water circulating in the coil is
still cold. If there is a bridge between these terminals, the controller deduces that the water is still hot.
- For P31 = 2, the controller waits to receive the water temperature from the central management unit before starting in heating or
cooling mode (if it does not receive a temperature value, it will not start its heating or cooling control sequence and will indicate
alarm E11)
7 - SPECIFICATIONS OF SENSORS USED BY THE V3000
All the sensors used by the V3000 (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
8 - WATER TEMPERATURE MEASUREMENT
EN7515935-00 EN - 10