Siemens LMV5 Series Basic Documentation page 181

Determination of the
maximum cable length
Siemens Building Technologies
HVAC Products
The maximum cable length between transformer and CAN bus users is dependent on
the type of cable (cross-sectional area), the number of actuators and the type of
actuator used (current).
The following graphs can be used to determine the maximum CAN bus cable lengths
between the transformer and group of actuators or the AZL5..., depending on the
relevant influencing factors.
The assumption was made that the actuators within the group are close to one another.
The minimum cross-sectional area for the system examples shown results from the
start of the curve.
The maximum cable lengths for the defined system cables AGG5.640 and AGG5.630
result from the points of intersection in the graph.
50
48
46
44
42
40
38
36
34
32 AGG5.630 / 631
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
AGG5.630 / 631 (cable type 2)
AGG5.640 / 641 (cable type 1)
1 x SQM45
1 5
2 x SQM45
2 6
3 x SQM45
3 7
4 x SQM45
4 8
CAN bus connection between transformer and actuator group
When connecting a PLL52... O2 module, the maximum permissible cable length of a
network is to be reduced by 2 m.
Example: - System cable:
- Actuators:
The point of intersection of the vertical line for the AGG5.640 (1.25 mm
(2 x SQM45.xxx) gives a maximum cable length of 33.4 m between the transformer and
the group of actuators.
The minimum cross-sectional area is 0.33 mm
Basic Documentation LMV51...
11 Mounting, electrical installation and service
AGG5.640 / 641
0.5
2 x SQM48
1 x SQM45 + 1 x SQM48
2 x SQM45 + 1 x SQM48
3 x SQM45 + 1 x SQM48
AGG5.640 (connecting cable to the actuators)
2 x SQM45...
2
.
1.25
Cross-section in mm
2
2
) and curve
181/278
CC1P7550en
01.10.2003