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Siemens Desigo Room automation - Engineering, mounting and installation CM111043en_14
Smart Infrastructure Wiring of field devices (without bus) 2020-10-30
Another limiting factor for cable length is hum injection for certain sensitive signal
types:
Signal t
ype
Normal hum
Reduced hum
mA
eff
Can be maintained
with cable length
mA
eff
Can be maintained with
cable length
/ shield
TXM1.8U AI NTC100K -- -- 0.05 30 m / 100 ft (80 m with shield *)
AI NTC10K -- -- 0.05 30 m / 100 ft (80 m with shield *)
All other
signal types
0.5 300 m / 1000 ft 0.05 300 m / 10000 ft
DXR2...
AI NTC100K
-- -- 0.05 30 m / 100 ft
(80 m / 260 ft with shield *)
AI NTC10K
-- -- 0.05 30 m / 100 ft
(80 m / 260 ft with shield *)
AI NTC3K
-- -- 0.05 30 m / 100 ft
(80 m / 260 ft with shield *)
AI R100K
-- -- 0.05 30 m / 100 ft
(80 m / 260 ft with shield *)
All other
signal types
0.13 80 m / 260 ft 0.05 80 m / 260 ft
*) Connect the shield to system neutral ^ on one end.
The measured value functions are already adjusted with a line resistance of 1 ohm
and the graphs below take account of this.
Exception: NTC3K, NTC10K and NTC100K.
The graphs below are for copper cable.
Measured value error due to line resistance
2
1
0
100 200 300
F [K]
L [m]
-0,21
1 mm
²
1,5 mm²
2,5 mm²
10762d034
0,6 mm Ø
Formula: F =
4.7
1
A57
L2
-
·
·
A Cable cross-section in mm
2
F Measured temperature error in K
L Cable length in m
Hum injection
Line resistance
compensation
("Sensor calibration")
Measured value error
LG
-
Ni 1000
Key