User Manual

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Siemens TX-I/O Engineering and installation guide CM110562en_13
Building Technologies Principles of electrical design 2019-05-15
AC24 V: 1 transformer
(AC 24 V must be fed from
one sub-island to the other)
AC 24 V: 2 transformers
(AC 24 V is supplied
separately for each sub-
island)
A) Round cables:

up to 50 m
admissible
10562z136
CD CS
AC 24 V
T
CD CS
T
10562z137
B) Coaxial cable and
round cables

up to 100 m
admissible
AC 24 V
CD
CS
AC 24 V
CD
CS
T
T
10562z139
CD
CS
CD
CS
T
T
10562z138
(Earthing:
see Section
6.4, 6.4.2)
10562z121
CD
T
1
T
T T
CS
T
2
AC24 V: 1 transformer
(AC 24 V must be fed from one sub-island to the other)
C) 2coaxial cables
(e.g. existing system
with remote P-bus)

up to 75 m
admissible
PC PU PD
CS
CD
T
GND
CS CD
T
10562z140
Forbidden (capacitance too high) 
Admissible cable
combinations
Example