Carrier CCU - 13 Bus for Connection to an Rs485 Modbus Cms; Bus Connection between the Units and the CMS

13 - BUS FOR CONNECTION TO AN RS485 MODBUS CMS
13.1 - Bus connection between the units and the CMS
The communication bus between the units and the CMS is a 2-wire RS485 bus
The green light indicates that the data sent by the CMS to the CCU CONTROLLER has been received.
The yellow light indicates that data has been sent by the CCU CONTROLLER to the CMS.
To CMS
Multiconductor cables, shielded,
jacketed (shielding with braiding)
length between the 1st and the
last CCU CONTROLLER:
1000 m
1: Line A or +
2: Line B or -
3: Earth
J10
COM1
1 2 3
ON
OFF
J10
COM1
1 2 3
ON
OFF
J10
COM1
1 2 3
ON
OFF
Line A or +
Line B or +
Earth
1st Unit
Intermediate unit(s)
Last unit
Multiconductor cables, shielded,
jacketed (shielding with braiding)
length between the 1st and the
last CCU CONTROLLER:
1000 m
1: Line A or +
2: Line B or -
3: Earth
To ensure correct operation, the
line must be polarised.
COM1: Line termination resistor switch
- First unit = OFF
- Intermediate unit = OFF
- Last unit = ON
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