Viessmann Vitoligno 300-C Installation And Service Instructions Manual page 31

Electrical connections
2. Route the internal and external cables as follows:
■ Route the cables in the cable guide.
The cable entry is only available after the casing
has been fitted.
■ Cables must be fastened to the retaining plates
with cable ties.
Ensure cables are routed to the appropriate side
■
of the control unit enclosure.
Note
Route 400/230 V cables and extra low voltage
(ELV) leads separately and bundle them close to
the terminals. This ensures that, in the event of a
fault, e.g. if a wire becomes detached, the wires
cannot drift into the adjacent voltage area.
Fig. 22
Electrical connection
When connecting external switching contacts and
components to the safety extra low voltage circuit of
the control unit, observe the safety requirements of
protection class II, i.e. 8.0 mm air gap/creep path and
2.0 mm insulation thickness towards live components.
For all components provided on site, ensure safe elec-
trical separation in accordance with EN 60335 and
IEC 60065. This includes PCs and laptops.
(cont.)
1.
3.
3. Install other boiler accessories and connect the
corresponding cables – otherwise you will need to
remove casing panels that you have already fitted
again later.
Close the cover of the control unit enclosure again
after completing all connection work.
2.
!
Please note
Electronic assemblies can be damaged by elec-
trostatic discharge.
Prior to commencing any work, touch earthed
objects such as heating or water pipes to dis-
charge static loads.
Installation sequence
31