Operation Manual

6 720 645 349 (2010/09)
Installation (for contractors only) | 17
3.2.2 Electrical connection for wall mounting
B BUS connection from the controller to other
BUS subscribers:
Use electrical cable according to local codes
and requirements.
Permissible cable lengths from the BUS-enabled
Heatronic 3 to the controller:
B To prevent inductive interference: Route all LV
leads separately from cables carrying 220 to
240 V or 380 to 415 V (minimum separation
100 mm).
B In case of external inductive interference,
shield the cables.
This ensures that the cables are shielded from
external interference (e.g. heavy current
cables, overhead wires, transformer stations,
radio and television set, amateur radio
stations, microwave ovens etc).
Fig. 15 Controller connected to BUS-enabled
Heatronic 3.
Fig. 16 BUS links connected via branch box (A)
Permissible cable lengths to outside temperature
sensor:
Cable length Cross-section
≤ 80 m 0.40 mm
2
≤ 100 m 0.50 mm
2
≤ 150 m 0.75 mm
2
≤ 200 m 1.00 mm
2
≤ 300 m 1.50 mm
2
Tab. 6
1
2
4
BB
6 720 613 557-03.1R
ST 19
AF
B
B
AF
FW 100
Heatronic 3
If the BUS links feature different
cross-sections:
B Connect BUS links via a branch
box.
Cable length Cross-section
≤ 20 m 0.75 mm
2
... 1.50 mm
2
≤ 30 m 1.00 mm
2
... 1.50 mm
2
≥ 30 m 1.50 mm
2
Tab. 7
B
2
BB
A
B
2
BB
B
2
BB
6 720 612 220-08.1J
100 mm
100 mm