4 Assembly and connection
RITTAL cooling unit assembly and operating instructions 13
EN
4.6 Carrying out the electrical installation
4.6.1 Bus connection
(only in conjunction with several units
with a Comfort controller)
When using several cooling units, the serial device
interface X2 can be used to connect up to ten cool-
ing units with the bus cable (Model No. SK 3124.100).
When interconnecting, please note the following:
– De-energise the cooling units to be connected.
– Ensure proper electrical insulation.
– Make sure the cables are not laid in parallel to
power lines.
– Make sure that the lines are short.
4.6.2 Connection X3 for serial interface
The interface card (Model No. SK 3124.200) may be
connected to X3. This is used to evaluate system
messages in a PLC, for remotely setting parameters
and monitoring, or for integration into the facility
management system.
Note:
The electrical signals at the X2 interface are
of an extra-low voltage (not extra-low safety
voltages to EN 60 335-1).
Caution!
Regarding the last slave unit in the
group, do not, under any circumstances,
connect the remaining socket of the
Y cable SK 3124.100 into interface X3
of the cooling unit!