Technical Manual: TM80030
THERMICA WATER TO AIR COOLER
Model range: THERMICA10-VV-MMM-LLL
Revision: 1.0
Date of release: 2022-12-16
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Alarms
A0 is the parameter where the alarm sensor can be selected. In this application only one sensor is used,
thus the default and recommend value is 1.
A6 & A7 are the high and low temperature alarms. The default is set on respectively 35°C and 5°C. The
parameter values can be adjusted to the application in which the cooler is applied. The maximum alarm
temperature should never exceed 70°C.
Control circuit
C1 is the setpoint of the cooler. If the fluid reaches this temperature the controller will provide a 10V signal
to the fan and the fan will run on 100% rpm. See Figure 13.
C7 & C8 are the respectively high and low setpoint limits. These are indicated in Figure 13 by the green
and blue dashed lines. Parameter C1 can be adjusted within these lines.
Fan control
F66 is the proportional bandwidth which determines the controller output based on fluid temperature. It
acts as a linear line between the setpoint (+offset) and the setpoint (+offset) minus the value entered. See
the different lines in Figure 14.
F67 is the parameter which defines the minimum percentage of fan input. It is recommended to leave this
at 0% at the minimum. The fan requires at least 1V signal to operate.
F69 is the parameter which defines the maximum percentage of fan output. This is done by minimizing
the controller output through the fan. (100% = 10V; 0% = 0V)
F67 and F69 are depicted in Figure 14. The minimum and maximum setting are capping the voltage
output of the controller. If the green line (F66 of 30°C) is followed, the controller will not send a higher
signal than 8V as output regardless of the fluid temperature.
F71 operates as an offset for C1. The value entered in F71 will be added to C1 in all situations.
Example (see Figure 13)
Parameter
Description of function
A4
Switching hysteresis for alarm
A6
Upper absolute alarm limit
C1
Setpoint
F66
Proportional range P controller
F69
Maximum speed fan
The fan signal voltage will be activated when the supply temperature of the coolant is higher than 20°C.
Since the fan requires a signal of at least 1V to operate, the fan will be powered at temperatures higher
than 21°C. The fan will be fully powered (100%) when the coolant supply temperature reaches a
temperature of 33°C. The alarm will activate when the coolant supply temperature reaches a temperature
of 35°C and will deactivate when the temperature decreases under a value of 34°C.
NOTE:
It is important to understand the application of the cooler well before changing the
parameter settings.
