CIAT Magister 2 Series, Установка, Эксплуатация, Пусконаладка, Обслуживание

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16.2 Water temperature setpoint adjustment
The control mode is set using parameter P141.
Value 1: set to water return.
Value 2: set to water supply.
Value 3: set to water supply with compensation by water return.
Setpoint 2 allows a similar shift if control adjusted based on the outdoor air (If P127 = Yes or P131 = Yes) or allows the control mode to be
changed if P54 (storage) = Yes.
16.3 Adjustment of water temperature setpoint if P7
≠ I
NVERTER
16.3.1 Water return control (P141 = 1):
The temperature used to adjust the setpoint is measured by:
- the inlet sensor on heat exchanger 1 if P2 = air-to-water or reversible air-to-water, if P2 = water-to-water and cooling mode,
- the hot water sensor if P2 = water-to-water and heating mode.
The difference between the control temperature the setpoint is compared to the stage differential and the interstage differential. Depending on
the result, it will be necessary to either turn on an additional stage or to turn one off.
Each stage is turned on at 60-second intervals and the shut off at 1-second intervals.
The related parameters are as follows:
P143: Stage differential
P144: Interstage differential P251: Control setpoint

In cooling mode:
- A call is made for an additional stage if T > Se SD + (ISD × NSO)
- A call is made to stop a stage if T < Se (ISD × NSO-1)
Where:
T: Control temperature (measured).
STP: Setpoint
SD: Stage Differential (P143)
ISD: Interstage Differential (P144)
NSO: Number of Stages On
Example: Two-stage water chiller
Parameter settings: STP = 10°C, SD = 2 K, ISD = 1.5 K

In heating mode:
- A call is made for an additional stage if T < STP - SD - (ISD × NSO)
- A call is made to stop a stage if T > STP - (ISD × NSO-1)
Where:
T: Control temperature (measured).
STP: Setpoint
SD: Stage Differential (P143)
ISD: Interstage Differential (P144)
NSO: Number of Stages On
Example: Two-stage water heater for a water temperature range of 35-40°C.
Parameter settings: STP = 40°C, SD = 2 K, ISD = 1.5 K.
Stage 1 Stage 2
On Off On Off
12 10 13.5 11.5
Stage 1 Stage 2
On Off On Off
38 40 36.5 38.5
R E T U R N T E M P . : - x x . x °
S E T P O I N T : - x x . x °
Water inlet temp.
STP
Stage 2
Stage 1
Water inlet temp.
STP
Stage 2
Stage 1