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cally stops the cycle in progress.
The values calculated by Auto-tuning are auto-
matically stored in the instrument’s memory at
the end of the correct PID parameters tuning. 
To activate the SELF-TUNING function proceed
as follows
1) Program and activate the desired Set Point.
2) Program par. "Cont" =Pid.
3) Program par. "Func" according to the process
to be controlled through output 1rEG.
4) Program an output as 2rEG if the instrument
controls a dual-action plant 
5) Program par. "SELF" = yES
6) Exit from the parameter programming.
7) Connect the instrument to the controlled
plant.
8) Activate Self-tuning selecting par. “tunE” in
the main menu (or by correctly programming
key F).
When the Self-tuning function is active, the led
AT/ST is permanently lit up and all the PID para-
meters ("Pb", "Int", "dEr", etc.) are no longer
visualized.
To stop the Auto-tuning cycle or deactivate the
Self-tuning function select one of the control
types : "rEG", "OPLO" or "OFF" from the menu
“SEL”. If the instrument is switched off during
Auto-tuning or with the Self-tuning function
activated, these functions will remain activated
the next time it is switched on.

DYNAMIC SET POINT (RISE RAMP)
All the parameters referring to the ramps func-
tioning are contained in the group “]rEG”.
It is possible to reach the set point in a prede-
termined time (in any case longer than the time
the plant would naturally need). This could be
useful in those processes (heating or chemical
treatments, etc.) where the set point has to be
reached gradually, in a predetermined time.
Once the instrument has reached the first Set
Point (SP1) it is possible to have automatic
switching to the second Set Point (SP2) after a
set time, thus obtaining a simple automatic
thermic cycle.
These functions are available for all the pro-
grammable controls (PID single and double
action, ON/OFF and Neutral Zone ON/OFF).
The function is determined by the following
parameter: 
"SLor" - Gradient of rise ramp  (Process value <
Set point) expressed in unit/minute. 
Note: In case of PID control, if Auto-tuning is
desired whilst the ramp function is active, this
will not be carried out until the tuning cycle has
been completed.
It is therefore recommended that Auto-tuning
be started avoiding activating the ramp function
and, once the tuning is finished, deactivate
Auto-tuning  (“Auto” = OFF), program the
desired ramps and, if it automatic tuning is
desired, enable the Self-tuning function.

Examples with starts from values lower than
SP and with decreasing of SP.

EWTQ 905

5/8

LoAb

off

ON

AL1

AL1

PV

HiAb

HAL1

time

off

ON

AL1

PV

time

HAL1

off

off

ON

OUT

off

off

ON

OUT

AL1

SP1

[Unit]

PV

SP1 Value

change

SP1

time [min.]

SLor

SLor

LoAb = ABSOLUTE LOW ALARM: The alarm is
activated when the process value goes below
the alarm threshold set on parameter "AL1”.
With this mode is possible to program the mini-
mum and the maximum set  of  “AL1” by “AL1L”
and “AL1H” parameters.

HiAb = ABSOLUTE HIGH ALARM: The alarm is
activated when the process value goes higher
than the alarm threshold  set on parameter
"AL1". With this mode is possible to program
the minimum and the maximum set  of  “AL1”
by “AL1L” and “AL1H” parameters.

LodE

ON

off

PV

SP1

-AL1

HAL1

time

off

ON

SP1

AL1

PV

HidE

time

HAL1

ON

off

off

off

off

ON

OUT

AL1

OUT

AL1

LHAb = ABSOLUTE BAND ALARM: The alarm
is activated when the process value goes under
the alarm threshold set on parameter "AL1L" or
goes higher than the alarm threshold set on
parameter "AL1H".

LodE = DEVIATION LOW ALARM: The alarm is
activated when the process value goes below
the value [SP + AL1]. With this mode is possible
to program the minimum and the maximum set
of  “AL1” by “AL1L” and “AL1H” parameters.

LHAb

ON

off

AL1H

AL1L

PV

ON

time

off

HAL1

HAL1

SP1

AL1L

AL1H

PV

time

LHdE

HAL1

HAL1

off

off

ON

ON

off

off

OUT

AL1

OUT

AL1

HidE = DEVIATION HIGH ALARM: The alarm is
activated when the process value goes above
the value [SP + AL1]. With this mode is possible
to program the minimum and the maximum set
of  “AL1” by “AL1L” and “AL1H” parameters.

LHdE = DEVIATION BAND ALARM: The alarm
is activated when the process value goes below
the value [SP + AL1L] or goes above than the
value [SP + AL1H]

ALARM FUNCTIONING (AL1)
The alarm is depending on the process value
(AL1) and before to set his functioning it’s nec-
essary to establish to which output the alarm
has to correspond to.
First of all it’s necessary to configure, in the
parameters group “]Out”,  the parameters rela-
tive to the outputs required as alarm (“O1F” ,
“O2F”) programming the parameter relative to
the desired output as follows :
= ALno if the alarm output has to be ON when
the alarm is active, while it’s OFF when the
alarm is not active

= ALnc if the alarm output has to be ON when
the alarm is not active, while it’s OFF when the
alarm is active 
= ALni if the alarm output has to be ON when
the alarm is not active, while it is OFF when the
alarm is active but with reverse led indication
(led ON= alarm OFF).
Have now access at the group “]AL1”, and pro-
gram on par. “OAL1” , to which output the
alarm signal has to be sent.
The alarm functioning is instead defined by
parameters (see Group “]AL1” (parameters
relative to alarm AL1
):

"AL1t" – ALARM TYPE : the alarm output can behave in six different ways.

Содержание EWTQ 905

Страница 1: ...figuration para meters menu Once the desired item has been selected push key set to confirm Selecting OPEr and ConF gives the possibili ty of accessing other menus containing addi tional parameters an...

Страница 2: ...with normalised analogue input signals it is first nec essary to program the desired resolution on par dP 0 1 1 0 1 2 0 01 3 0 001 and then on par SSC the value that the instrument must visualise at t...

Страница 3: ...Point SP and on the hysteresis HSEt The control works in the following way it deac tivates the outputs when the process value reaches the Set Point and it activates the output 1rEG when the process va...

Страница 4: ...matically calculate the fol lowing parameters Pb Proportional Band tcr1 Cycle time of the output 1rEG Int Integral Time dEr Derivative Time FuOC Fuzzy Overshoot Control and for the Double Action PID c...

Страница 5: ...of SP EWTQ 905 5 8 LoAb off ON AL1 AL1 PV HiAb HAL1 time off ON AL1 PV time HAL1 off off ON OUT off off ON OUT AL1 SP1 Unit PV SP1 Value change SP1 time min SLor SLor LoAb ABSOLUTE LOW ALARM The alarm...

Страница 6: ...for temperature probes tc J K RTD Pt 100 IEC PTC KTY 81 121 990 W 25 C NTC 103AT 2 10KW 25 C or mV sig nals 0 50 mV 0 60 mV 12 60 mV or normal ized signals 0 4 20 mA 0 1 V 0 1 5 V 0 2 10 V Normalized...

Страница 7: ...AL1H High threshold band alarm AL1 or Maximum set alarm AL1 for high or low alarm AL1L 9999 9999 20 HAL1 Alarm AL1 hysteresis OFF 9999 1 21 AL1d Activation delay of alarm AL1 OFF 9999 sec OFF 22 AL1i...

Страница 8: ...rms if the relative parameters ALni have been programmed yES 44 5 98 48 OUT2 48 ST AT OUT1 9 5 SET EWTQ 905 F set MAX 9 mm PANEL GASKET BRACKET TYPE 1 BRACKET TYPE 2 MECHANICAL DIMENSIONS PANEL CUT OU...

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