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SOM 9s
The controller compares the temperature at sensor S1 to
the temperatures at sensors S2 and S4. If the measured
temperature differences are higher than the adjusted switch-
on temperature differences, the pump (R1 and R2) will be
activated and the corresponding tank will be loaded up to
the adjusted maximum temperature. Tank 1 is loaded with
priority.
Heat exchange from tank 1 to tank 2 (R3) is possible with
another temperature differential function (S3-heat source/
S4-heat sink).
Adjustment channels
Channel
Sub channel 1
Sub channel 2 Factory
setting
Change to
Description
Page
ARR
1
17
System
78
LOAD1 >
Loading 1
DT1O
12 °R
Switch-on temperature difference 1
78
DT1F
8 °R
Switch-off temperature difference 1
78
DT1S
20 °R
Set temperature difference 1
78
RIS1
4 °R
Rise 1
78
S1MAX
140 °F
Tank maximum limitation 1
78
SMXS1
2
Sensor tank max 1
79
LOAD2 >
Loading 2
DT2O
12 °R
Switch-on temperature difference 2
78
DT2F
8 °R
Switch-off temperature difference 2
78
DT2S
20 °R
Set temperature difference 2
78
Sensor/Ter-
minal
Designation
Description
S1
TCOL
Temperature collector
S2
TST1B
Temperature tank 1 bottom
S3
TSTT
Temperature tank 1 top
S4
TST2B
Temperature tank 2 bottom
S5
Optional sensor for measurement
purposes or options
VFS
RPS
V40
Relay
Description
R1
Solar pump tank 1
R2
Solar pump tank 2
R3
Heat exchange pump
R4
optional:
Thermal disinfection
Parallel relay
Heat dump
System 17
2-tank solar system with pump logic and heat exchange control
R3
R2
R1
S4
S3
S2
S1
Temp. Sensor
Pt1000
L
R3
R2
R1
GND
S1
S2
S3
S4
S5
VBus
PW
M
1
PW
M
2
N
R4
V4
0
L'
VFS
RPS
out
in