Basic Documentation

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Siemens VAV compact controller G..B181.1E/3 | VAV modular controller ASV181.1E/3 CE1P3544en
Smart Infrastructure 2021-10-26
The chart below applies to AC 24 V operating voltage and shows the permissible
cable length L as a function of power P, and the cross-sectional areas as a
parameter.
300
200
100
0
0
8 16 24 32
L [m]
P
[VA, W]
2.5 mm²
1.5 mm²1 mm²
0.5 mm²
0.75 mm²
4614D01en
The values in [VA, W] on the P-abscissa are allocated to the permissible voltage
drops (U/2U = 4 %) on line length L as per the above table and the basic diagram.
P is the decisive power consumption of all VAV compact controllers connected in
parallel.
U

U/2

U/2
R
L
R
L
L
L
U
−
U
4614D09
M
The following formulas can be used to calculate the maximum cable lengths.
Operating voltage
Permissible
voltage drop per
line
Formula for cable length
AC 24 V
4 % of AC 24 V
L =
P
A1313 •
m
1 % of DC 10 V
L =
(DC) I
A 5.47 •
m
A Cross-sectional area in [mm
2
]
L Permissible cable length in [m]
P Power consumption in [VA] or [W];
refer to the VAV compact controllers’ type field
I(DC) DC current portion on G0 line in A
L/P chart for
AC 24 V
Note on chart
Basic diagram:
Voltage drop on the
supply lines
Formulas for
cable length