Schwank ThermoControl Plus 2 - Manual (Page 28)

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6.12 Communication connection
Two types of optional communication cards can be used and connected to the "Communication"
terminal (only one type can be used at a time):
-CM485 card: Modbus (RS485) output, standard interface to building and industrial supervisory
systems. The output of this card is optically isolated from the controller.
-CM232 card: RS232 output, built-in 3-weeks data logger. Direct connection to telephone modem
or PC. Stored data can be downloaded to PC, remote setting of the controller from the PC.
The signal output ground of the CM232 module is directly connected to the controller's
common ground "COM". If the signal line of the connected computer is grounded, the
common ground "COM" of the controller will be grounded as well. This will change state
from isolated to grounded.
6.13 Common fault signal
In case of any operational error the red “ERROR” symbol starts to blink, simultaneously the error
relay switches on (connections 1, 2, 3). The display shows the affected control zone. Type and
cause of the problem is also indicated by other symbols displayed. To select another control zone
press “ZONE” - in doing so, the red “ERROR” signal won’t disappear, because the cause of the
problem is not yet solved. The blinking “ERROR“ signal and the activated error relay can be
deactivated by switching off the operational function of the zone using the button.
Sensor error: The temperature sensor is not properly
connected. It is damaged or short-circuited. Verify connections
and wires. In case of any sensor error the controller does not
switch off the heater zone (relay output is kept activated).
Battery error: Battery low or discharged. Replace the battery
immediately. The battery is located inside the control unit cover.
Type: 1.5V (AA). Use long-life batteries. Before changing the
batteries please read the general security instructions – and in
particular Section 4.4.4!
Alarm signal: Does not point out the kind of operational error.
It only shows that an error message has arrived at the “alarm
contact”. The controller switches off all heaters and exhaust
fans. If the “alarm contact” is not used the connections should
be bypassed.
This display is a very rare error: a forced position of a button at
the front panel. Please check!
This is an error message (option) of a heater (connections 72-
73). The operation mode of the controller is not changed due to
the error signal.