Danfoss ECL Comfort 210 Operating Manual page 28

Operating Guide ECL Comfort 210/296/310, application A237/A337
2.5.4 Electrical connections, master / slave systems
The controller can be used as master or slave in master / slave
systems via the internal ECL 485 communication bus (2 x twisted
pair cable).
The ECL 485 communication bus is not compatible with the ECL
bus in ECL Comfort 110, 200, 300 and 301!
Terminal Description
30 Common terminal
31* +12 V*, ECL 485 communication bus
32
B, ECL 485 communication bus
33
A, ECL 485 communication bus
* Only for ECA 30 / 31 and master / slave communication
2.5.5 Electrical connections, communication
Electrical connections, Modbus
ECL Comfort 210: Non-galvanic isolated Modbus connections
ECL Comfort 296: Galvanic isolated Modbus connections
ECL Comfort 310: Galvanic isolated Modbus connections
28 | © Danfoss | 2017.05
Type
(recomm.)
Cable 2 x
twisted pair
Total cable length: Max. 200 m (all sensors incl. internal ECL 485
communication bus).
Cable lengths of more than 200 m may cause noise sensibility (EMC).
ECL 485 bus cable
Maximum recommended length of the ECL 485 bus is calculated like
this:
Subtract "Total length of all input cables of all ECL controllers in the
master - slave system" from 200 m.
Simple example for total length of all input cables, 3 x ECL:
1 x ECL
3 x ECL
3 x ECL
3 x ECL
Total:
Maximum recommended length of the ECL 485 bus:
200 - 81 m = 119 m
15 m
Outdoor temp. sensor:
18 m
Flow temp. sensor:
Return temp. sensor: 18 m
Room temp. sensor: 30 m
81 m
VI.LG.R3.02