Overview
Master/Slave Operation — 24.09.2015
English — 5
3.1
Function
In a multiple-unit network, the water levels in the expansion tanks are monitored and maintained. The master controls the pressure in
the slaves. The master transmits via RS-485 signal line its current level value to the slaves. The water level in the slave is regulated if the
difference in water levels between master and slaves exceeds a specific value.
The slave supports the master in maintaining the pressure:
•
Increasing water level.
– The slave's compressor or pump is started.
– The optional second compressor or second pump are switched on when the water level does not reach the master level within
the defined time.
– The compressors or pumps are shut down when the water level is the same as in the master.
– The slave is switched to individual mode when the pressure exceeds the maximum pressure.
– The slave is switched to master/slave mode when the pressure drops below the maximum pressure.
•
Decreasing water level.
– The overflow valve is opened.
– The optional second overflow valve is opened when the water level does not reach the master device level within the defined
time.
– The overflow valves are closed when the water level is the same as in the master.
– The slave is switched to individual mode when the pressure drops below the minimum pressure.
– The slave is switched to master/slave mode when the pressure drops below the minimum pressure.
Note!
The parameters for the level values in the controller are pre-set at the factory. If necessary, adjust the factory settings to
the system-specific conditions.
– For adjusting factory settings, see chapter 5.2 "Setting the controller parameters" on page 11 .
