following parameters apply on selection CHA only:
(value range SP00 to SP02)
Selects the programme setpoint used for the cascade control, ie. the programme setpoing for the target
(value range CH00 to CH02)
Selects the master control channel (loop). The basic idea of a cascade control is as follows: An application
requires a large target (e.g. a piece of aluminium) to follow a temperature curve. An appropriate solution is
using an air convection kiln. Using an ordinary control it will give different problems depending on the position
of the thermocouple: When sensing the ambient temperature the actual temperature of the target
(aluminium) will be far (might be even hundreds of degrees centigrade) behind since it is very lag. Sensing the
target temperature might cause damage to the kiln since the controller does not pick up the temperature of
the heaters. Additionally, temperature oscillations are likely when the target temperature is getting close. A
cascade control eliminates these problems and works as follows: Two control channels are combined. The
master control channel is configured as normal, ie. using the programme temperature as setpoint and the
target temperature as actual temperature. The output of this channel is used to create a 2nd temperature
setpoint according to the settings in this section. This setpoint and the actual ambient temperature are
assigned to the slave control channel driving directly the heating device of the kiln. Note that the master
control channel is configured as heating/cooling loop with a wide proportional range and slow integral time
(P/I/D = 10.0% / 400 s / 0 s)
(value range -9999 to 9999)
Limits the maximum difference in temperature between the target and the ambient temperature. Used to
avoid damage of the target if sensitive. A high limit, however, speeds up the process of the target reaching the
programme setpoint
(value range -9999 to 9999)
Limits the maximum ambient temperature. Used to avoid damage of the target if sensitive. A high limit,
however, speeds up the process of the target reaching the programme setpoint
The control loops are designed to operate in totally different modes. Each operation mode can be tuned
individually
(options END, PID, C-PID, D-HYS, P-DIR, ---)
Depending on your application different control algorithms are available
PID: Default control algorithm suitable for most applications
C-PID: As before, but provides independent disable feature for heating and cooling range. Important on
heating/cooling applications where heating and cooling depends on external conditions. Also used to avoid
heating and cooling ranges chasing each other. Activation is done by any bit (e.g. a digital output). Typical
applications are gas kilns where heating range (0 to +100%) is disabled once the burner control bit goes OFF
D-HYS: Hysteresis control for heating devices which require either temperature deviation or do not allow short
cyclic activation (e.g. discontinuous burners)
P-DIR: Direct control. The setpoint is directly converted into a control value refering to the given value
boundaries. Typical application is setting a flap position directly (e.g. 0 to 100%)
(value range SP00 to CH19)
Selects the setpoint used for this control channel
(value range SP00 to CH19)
Selects the process value used for this control channel
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