Siemens OpenAir GMA 1 Series Technical Basics page 22

Line length/consumption
AC/DC 24 V
L [m]
300
200
100
0
0
Notes on diagram
P&I diagram:
Voltage drop on the supply
lines
Formula for line length
22/44
Siemens
Building Technologies
The diagram applies to AC/DC 24 V and shows the permissible line length L as a
function of consumption P and as a parameter of the line cross sections.
0.75 mm² 1 mm²
0.5 mm²
8
∂ The values in [VA, W] on the P-axis are allocated to the permissible voltage drops
( Χ U/2U = 4 %) on line L as per the above table and to the P&I diagram.
∂ C is the primary power consumption for all actuators connected in parallel.
ΧU/2
R
L
U
R
L
Χ U/2
The maximum line length can be calculated using the following formula.
Operating voltage
AC/DC 24 V
AC 230 V
Line cross section in [mm
A
L Permissible line length in [m]
P Power consumption in [VA] or [W];
The value is printed on the actuator's type plate.
DC current portion in line G0 in ΖA∴
I(DC)
GMA..1 actuators with spring return
2.5 mm²
1.5 mm²
16
L
U,ΧU
M
L
Perm. voltage drop / line
4 % of AC/DC 24 V
1 % of DC 10 V
2 % of AC 230 V
2
]
P
24 32
Formula for line length
1313 ∂
A
Ζ ∴
L = m
P
5.47 ∂
A
Ζ ∴
L = m
I (DC)
1313 ∂
A
∂ Ζ ∴
L = m
46
P
[VA, W]
CM2Z4614en
2018-01-11