User manual MKA 120
Conforms to
Issue 07.07.2021_01 Page 12
5.1 Entering nominal values
The entry function for nominal values will automatically be terminated after 10 seconds if no
further key pad buttons are pressed.
The nominal value that was entered last is saved.
Hint
Nominal value entry is only possible via the shortcut buttons.
5.2 Switching off nominal values
Be aware
Switching off nominal values:
Nominal values in the controller can also be negative. Therefore the value
„0“ is also a valid
nominal value. If you want to switch off a nominal value in a program step, e.g. the core
temperature, the button has to be pressed repeatedly until the value
„OFF“ appears.
5.3 Nominal temperature
Nominal value for chamber temperature control. The chamber temperature is regulated via the
heating relay (
when the actual value is smaller than the nominal value
) and/or cooling relay
(
when the actual value is higher than the nominal value
). If two nominal values „Chamber min“
and „Chamber max“ have been enabled for temperature control, the heating process will use
nominal value „
Chamber min
“ and the cooling process will use „
Chamber max
“.
5.4 Nominal core temperature
Be aware
Shut-down condition:
If you have enabled the nominal core temperature value in a step and the actual
temperature of the core sensor reaches this nominal value, the step will be terminated.
The controller works with two types of core shut-down:
Positive core shut-down (heating operation)
If the pre-programmed nominal chamber temperature value is higher than the nominal core
temperature value, the controller will switch to the next step as soon as the actual core
temperature is higher or equal to the nominal core temperature.
Negative core shut-down (cooling operation)
If the pre-programmed nominal chamber temperature value is lower than the nominal core
temperature value, the controller will switch into the next step. When the actual core
temperature is smaller or equal to the nominal core temperature the controller will also switch
into the next step.
5.5 Step time
The step time is the duration of a step.
Entering a step time
While a step is running the step time is counted backwards. When the pre-programmed step
time has elapsed, the controller will switch into the next step.
