7.3 Several controllers in the same system
When ECL Comfort controllers are interconnected by means of
the ECL 485 communication bus (cable type: 2 x twisted pair), the
master controller will broadcast the following signals to the slave
controllers:
•
Outdoor temperature (measured by S1)
•
Time and date
•
DHW tank heating / charging activity
Furthermore, the master controller can receive information about:
•
the desired flow temperature (demand) from slave controllers
•
and (as from ECL controller version 1.48) DHW tank heating /
charging activity in slave controllers
Situation 1:
SLAVE controllers: How to make use of the outdoor
temperature signal sent from the MASTER controller
The slave controllers only receive information about outdoor
temperature and date / time.
SLAVE controllers:
Change the factory set address from 15 to address 0.
•
In
, go to System > Communication > ECL 485 addr.
ECL 485 addr. (master / slave address)
2048
Circuit
Setting range
Choose
0 ... 15
0
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
Outdoor temp. sensor:
15 m
3 x ECL
Flow temp. sensor:
18 m
3 x ECL
Return temp. sensor:
18 m
3 x ECL
Room temp. sensor:
30 m
Total:
81 m
Maximum recommended length of the ECL 485 bus:
200 - 81 m = 119 m
In a system with MASTER / SLAVE controllers, only one MASTER
controller with address 15 is allowed.
If by mistake more MASTER controllers are present in an ECL 485
communication bus system, decide which controller is to be MASTER.
Change the address in the remaining controllers. However, the system
will operate but not be stable with more than one MASTER controller.
In the MASTER controller, the address in ‘ECL 485 addr. (master / slave
address)’, ID no. 2048, must always be 15.
Navigation:
•
In
, go to System > Communication > ECL 485 addr.
SLAVE controllers must be set to another address than 15:
Navigation:
•
In
, go to System > Communication > ECL 485 addr.
'Demand offset' with a value is to be used in the Master controller only.
VI.GU.L2.02
© Danfoss | 2017.09 | 183
Operating Guide ECL Comfort 210/296/310, application A275/A375
