User Manual
Application examples
Output configuration Modulating load input with
switching command outputs
Load input,
start condition
A B C D
Number of
stages or
aggregates
Run priority
changeover
4
1
Start
(Example 1) A+B+C+D a d d d d Yes
Description:
- Control of refrigeration machine with 4 compressors to outlet temperature.
- Run priority changeover includes changeover incase of fault.
Plant diagram Function diagram
X
P
0 %
0 %
Q
X
P
100 %
B
A
C
D
100 %
Q
A
B
C
D
3123D21
AI
DI
AO
DO
T
3123S46
4x
4
3
2
1
Configuration diagram
CD
C D
X
C D
Rotary
step switch 1
Main menu > Commissioning > Extra configuration > Aggregates > Rotary step switch >
Rotary step switch 1…2 >
Configuration
Operating line Setting
Type Linear
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Siemens Switching and monitoring device RMS705B CE1P3124en
Building Technologies Aggregates 01.04.2010