Operating instructions
31
3.6.6.3 - High-voltage units
High-voltage units can require special terminal preparation
to prevent moisture condensation and electrical arcing.
Follow electrical codes for high-voltage installation. The use
of vinyl tape is not recommended; a method for high-voltage
devices must be used.
3.6.6.4 - Electrical connection of the starter
The earth of the control equipment and the control box
(starter) must have equipotential.
3.6.6.5 - Control wiring
The transformer that supplies the control equipment is only
provided to supply the auxiliary control installation within
the power reserve limit indicated on the wiring diagram
supplied with the machine.
The communication bus cables and those provided for the
transmission of analogue signals that go to the outside of
the control boxes must be shielded. The shielding must be
connected to the whole cable circumference and both ends.
3.6.6.6 - Wiring between starter and compressor motor
For high-voltage motor wiring please contact the Carrier
factory.
Low-voltage (690 V or less) compressors have six terminal
studs. Depending on the type of starter employed, between
3 and 6 leads must be run between the starter and the motor.
If only 3 leads are used, jumper the terminals as follows: 1 to
6, 2 to 4 and 3 to 5 (see the table in Fig. 23 for the diameter
and distance between terminals).
The terminal studs must not take the weight of the leads:
use intermediate supports. Use a torque spanner to tighten
the terminal nuts to 60 Nm maximum, maintaining the
terminal with an additional spanner.
B 6 101,5 80 16
C 6 101,5 80 16
D 6 145 122 22,5
E 6 145 122 22,5
60 Nm 40 Nm
3.6.7 - Connect the starter cabinet to the control box
Connect the starter cabinet to the unit control box (Fig. 22).
In addition, connect the communication cable (SIO) from
the control box to the ISM board on the power wiring box.
The pressostat and pump operation return signal cables
may cross over between the control boxes.
3.6.8 - Carrier Comfort Network interface (CCN)
The Carrier Comfort Network (CCN) communication bus
wiring is supplied and installed by the electrical contractor. It
consists of shielded, 3-conductor cable with metallic braiding.
The system elements are connected to the communication
bus in a daisy chain arrangement. The positive pin of each
system element communication connector must be wired
to the positive pins of the system element on either side of
it. The negative pins must be wired to the negative pins.
The signal ground pins must be wired to the signal ground
pins. See Fig. 24 - “COMM1 CCN communication wiring
for multiple 19XR chillers” for the location of the CCN
network connector on the ICVC (J1) module.
When connecting the CCN communication bus to a system
element, a colour code system for the entire network is
recommended to simplify installation and checkout. The
following colour code is recommended:
+ 1 Red
Ground 2 White
- 3 Black
* Cable type to be used: shielded cable LIYCY
If a cable with a different colour scheme is selected, a similar
colour code should be adopted for the entire network.
Precautions must be taken to protect the signal against
external electromagnetic interference. The recommendations
depend on the installation configuration.