22
The parameter
has the same meaning as the heating time
cycle
.
The parameter
(cooling fluid) pre-selects the proportional
band multiplier
and the cooling PID time cycle
basing
on the type of cooling fluid:
Cooling fluid type
Air
1.00
10
Oil
1.25
4
Water
2.50
2
Once selected, the parameter
, the parameters
,
and
can however be changed.
9
Serial Communication
DRR245-21ABC-T is equipped with with RS485 and can receive/
broadcast data via serial communication using MODBUS RTU
protocol. The device can only be configured as a Slave. This function
enables the control of multiple controllers connected to a supervisory
system (SCADA).
Each controller responds to a master query only if the query contains
the same address as that in the parameter
. The addresses
permitted range from 1 to 254 and there must not be controllers with
the same address on the same line.
Address 255 can be used by the master to communicate with all the
connected equipment (broadcast mode), while with 0 all the devices
receive the command, but no response is expected.
DRR245 can introduce a delay (in milliseconds) in the response to the
master request. This delay must be set on parameter 72
Each parameter change is saved by the controller in the EEPROM
memory (100000 writing cycles), while the setpoints are saved with a
delay of ten seconds after the last change.
NB: Changes made to words that are different from those reported in
the following table can lead to malfunction.
