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GROUP “
]
rEG” (PARAMETERS RELATIVE TO THE CONTROL):
It contains the parameters relative to the control functioning.
Cont
– CONTROL TYPE: It permits to select one of the possible control mode offered by the instrument : PID (Pid), ON/OFF
with asymmetrical hysteresis (On.FA), ON/OFF with symmetrical hysteresis (On.FS), Neutral Zone ON/OFF (nr).
Func –
FUNCTIONING MODE OUTPUT 1rEG:
It permits to decide if the control output 1rEG has to actuate a reverse action,
as for example a Heating process ("HEAt") or a direct action, as for example a Cooling process ("CooL").
HSEt
–ON/OFF CONTROL HYSTERESIS: Semi-band relative to the Set Point which definers the activation and deactivation
values of the control output/s in case of ON/OFF control (On.FA, On.FS, nr).
Auto
– AUTOTUNING FAST ENABLE : this parameter permits to decide how the Autotuning has to be executed . The possible
selections are :
= 1 - if it’s desired to have the autotuning automatically, each time the instrument is switched on, at the condition that the
process value is lower (with “Func” =HEAt) or higher (with “Func” =CooL) than SP/2
= 2 - if it’s desired to have the autotuning automatically, the next time the instrument is switched on, at the condition that the
process value is lower (with “Func” =HEAt) or higher (with “Func” =CooL) than SP/2, and once the tuning is finished, the par.
“Auto” IS automatically swap into the OFF state
= 3 - - if it’s desired to activate the autotuning manually, through the selection of par. “tunE” in the main menu or though key
“U” properly programmed as “USrb” = tunE. In this case the autotuning starts without any control on the process value
condition. It’s recommended to use this option, starting the autotuning when the process value is as far as possible from the
Set Point because, in order to feature the Autotuning FAST with its best performances , it’s preferable to respect this condition
= OFF - Autotuning disabled.
When it’s occurring an Autotuning cycle, led AT blinks.
SELF
– SELFTUNING ENABLE: Parameter used to enable (yES) or disable (no) the Selftuning function. Once the function has
been enabled, the Selftuning has to be started selecting item “tunE”, in the main menu, or through key U properly
programmed (“USrb” = tunE).When the Selftuning function is active, led AT is permanently lighted, and all the PID parameters
("Pb", "Int", "dEr", ecc.) are not visualised anymore.
Pb
– PROPORTIONAL BAND: Width of the band around the Set Point within which the proportional control is performed.
Int
– INTEGRAL TIME: Integral time to be programmed in the PID algorithm, expressed in sec.
dEr
– DERIVATIVE TIME: : Derivative time to be programmed in the PID algorithm, expressed in sec.
FuOc
- FUZZY OVERSHOOT CONTROL: Parameter that permits to eliminate the variable over-shoots at the start up of the
process or at the changing of the Set Point. A low value of this parameter reduces the overshoot while a high value increase
it.
tcr1
– CYCLE TIME OF OUTPUT 1rEG : Cycle time of output 1rEG with PID control mode, expressed in sec..
Prat
– POWER RATIO 2rEG / 1rEG : Parameter where it’s possible to program the power ratio between the element
controlled by output 2rEG (ex.Cooling) and the element controlled by output 1rEG (ex. Heating) in case of PID double action
control.
tcr2
- CYCLE TIME OF OUTPUT 2rEG : Cycle time of output 2rEG with PID double action control mode, expressed in sec..
rS
- MANUAL RESET: Power Offset added to the power increase of the proportional term, in order to eliminate the error when
it’s not present the integral value. This parameter is only visualised when “Int” =0.
Parameters relative to the ramps, allowing the reaching of the Set Point in a predetermined time.
Furthermore, once the first Set (SP1) has been reached, it’s possible to have the automatic commutation on the second
Set (SP2) after a programmable time, obtaining in this way a simple thermal cycle (functions available for all the control
types)
SLor
– GRADIENT OF RISE RAMP: Gradient of rise ramp to actuate when the process value is lower than the active Set
Point, expressed in unit/minute.
Programming the parameter = InF the ramp is not active.
dur.t -
DWELL TIME: Dwell time of the Set Point SP1 before the automatic commutation on SP2 (expressed in hrs. and min.)
Through this parameter,
once the first Set (SP1) has been reached, it’s possible to have the automatic commutation on the
second Set (SP2) after a programmable time, obtaining in this way a simple thermal cycle.
Programming the parameter = InF the function is not active.
SLoF
- GRADIENT OF FALL RAMP: Gradient of fall ramp to actuate when the process value is higher than the active Set
Point, expressed in unit/minute.
Programming the parameter = InF the ramp is not active.
Parameters relative to the Soft-Start function, which allows to limit the control power, at the instrument switch on, for a
predetermined time. This function is only available for PID control, furthermore when the Soft Start is active, it’s not
possible to have the Autotuning function as this could supply an excessive power.
St.P
- SOFT START POWER:
If parameter “SSt” is programmed with a values different from OFF, this is the power given as output at the instrument switch
on, for the time “SSt”.
In the practice, the instrument works in manual condition and commutates into automatic control at the elapsing of time
“SSt”.
