Ascon Tecnologic - KM5P Line - ENGINEERING MANUAL - PAG. 14
2.
When LBA alarm is ON the instrument continues
to perform the standard control. If the process
response comes back into the programmed limit,
the instrument automatically resets the LBA alarm.
3.
This function is available only when the programmed
control algorithm is equal to PID (Cont = PID).
[52] LbAt - LBA time
Available:
When [56] Cont = PID
Range: •
oFF = LBA not used;
• 1... 9999 seconds.
[53] LbSt - Delta measure used by LBA during
Soft start
Available:
When [52] LbAt is different from oFF.
Range: •
oFF = loop break alarm is inhibit during soft start
• 1... 9999 engineering units.
[54] LbAS - Delta measure used by loop break
alarm (loop break alarm step)
Available:
When [52] LbAt is different from oFF.
Range:
From 1 to 9999 engineering units.
[55] LbcA - Condition for LBA enabling
Available:
When [52] LbAt is different from oFF.
Range:
uP
Enabled when the PID requires the maxi-
mum power only;
dn
Enabled when the PID requires the mini-
mum power only:
both
Enabled in both condition (when the PID re-
quires the maximum or the minimum power).
LBA application example:
LbAt (LBA time) = 120 seconds (2 minutes);
LbAS (delta LBA) = 5°C.
The machine has been designed in order to reach 200°C in
20 minutes (20°C/min).
When the PID demands 100% power, the instrument starts
the time count.
During time count if the measured value increases more
than 5°C, the instrument restarts the time count. Otherwise
if the measured value does not reach the programmed delta
(5°C in 2 minutes) the instrument will generate the alarm.
]
rEG group - Control parameters
The rEG group will be available only when at least one
output is programmed as control output (H.rEG or C.rEG).
[56] cont - Control type:
Available:
When at least one output is programmed as con-
trol output (H.rEG or C.rEG).
Range:
When two control action (heat & cool) are programmed:
Pid
PID (heat and cool);
nr
Heat/Cool ON/OFF control with neutral zone.
HSEt
HSEt
SP
PV
time
OUTH.rEG
(heating)
OUTc.rEG
(cooling)
off
ON
ON
off
off
ON
When one control action (heat or cool) is programmed:
Pid
PID (heat or cool);
On.FA ON/OFF asymmetric hysteresis;
On.FS ON/OFF symmetric hysteresis;
3Pt
Servomotor control (available when Output
2 and Output 3 have been ordered as “
M
”).
m
When a servomotor control is desired,
both
Out2
and
Out3
are to be selected as Heating or Cooling
(o2F = o3F = HrEG
or
o2F = o3F = c rEG).
Parameter
[56] cont
must be set as
3pt
.
HEAt - On.FA
OUT
H.rEG
SP
PV
HSEt
time
off
off
C ooL - O n.FA
OUT
C.rEG
SP
PV
HSEt
time
ON
ON
ON
off
off
ON
ON
ON
HEAt - On.FS
OUT
H.rEG
SP
PV
HSEt
HSEt
time
C ooL - O n.FS
OUT
H.rEG
SP
PV
HSEt
HSEt
time
ON
ON
ON
off
off
off
off
ON
ON
ON
Notes: 1.
ON/OFF control (heating action) with asymmetric
hysteresis:
• OFF when PV > SP;
• ON when PV < (SP - hysteresis).
2.
ON/OFF control (heating action) with symmetric
hysteresis:
• OFF when PV > (SP + hysteresis);
• ON when PV < (SP - hysteresis).
[57] Auto - Auto tune selection
Ascon Tecnologic has developed three auto-tune algorithms:
–
Oscillating auto-tune;
–
Fast auto-tune;
–
EvoTune.
1.
The
oscillating
auto-tune is the usual auto-tune and:
• It is more accurate;
• Can start even if PV is close to the set point;
• Can be used even if the set point is close to the
ambient temperature.
2.
The
fast type
is suitable when:
• The process is very slow and you want to be opera-
tive in a short time;
• When an overshoot is not acceptable;
• In multi loop machinery where the fast method
reduces the calculation error due to the effect of the
other loops.
3.
The
EvoTune
type is suitable when:
• You have no information about your process;
• You can not be sure about the end user skills;
• You desire an auto tune calculation independently
from the starting conditions (e.g. set point change
during tune execution, etc).
Note:
Fast auto-tune can start only when the measured
value (PV) is lower than (SP + 1/2SP).
Available:
When [56] cont = PID
Range:
-4... 8 where:
-4 Oscillating auto-tune with automatic restart at
all set point change;
-3 Oscillating auto-tune with manual start;
-2 Oscillating auto-tune with automatic start at the
first power up only;
-1 Oscillating auto-tune with automatic restart at
every power up;
0 Not used;
