45
Ecotower
COSMOGAS
6.17.3 - Connection of the communication
cable between GB indoor unit and STM
outdoor unit
To connect the modbus communication cable between the
indoor and outdoor units, proceed as follows (refer to Figure
6-24):
1.- Use a shielded bipolar cable, with a minimum section of
0.5 mm2;
2.- Remove the casing of the indoor unit (section 10.24);
3.- Access the two terminal blocks as shown in figure below;
4.- Lay the bipolar cable;
5.- Strip the cable;
6.- Connect the cable to terminals “A” and “B” of the indoor
unit (item “E”);
7.- Access the terminal block of the outdoor unit (Figure 6-23);
8.- Strip the cable;
9. - Connect the cable to terminals “A” and “B” of the indoor
unit, respecting the polarity performed on the indoor unit;
10. - Connect the cable shield to the ground terminal of the
outdoor unit only.
WARNING !!! Since the cables are subjected to
very low safety voltage (24Vdc), they must run in conduits
other than the 230Vac power supplies.
Figure 6-24 - Outdoor and Indoor unit connection
6 - INSTALLATION
PE N L
D
E
D
E
A B
A
B
D
: 230Vac electrical connection
E
: BUS connection
230Vac output connection
BUS connection
Cable clamp
Shielded cable
