The instrument allows for measuring calibration, which may be
used to recalibrate the instrument according to application needs,
by using par.
“OFSt”
and
“rot”.
Programming par. “rot”=1,000, in par. “OFSt” it is possible to set a
positive or negative offset that is simply added to the value read by
the probe before visualisation, which remains constant for all the
measurements.
If instead, it is desired that the offset set should not be constant for
all the measurements, it is possible to operate the calibration on
any two points.
In this case, in order to decide which values to program on par.
“OFSt” and “rot”, the following formulae must be applied :
“rot” = (D2-D1) / (M2-M1)
“OFSt” = D2 - (“rot” x M2)
where:
M1 =measured value 1
D1 = visualisation value when the instrument measures M1
M2 =measured value 2
D2 = visualisation value when the instrument measures M2
It then follows that the instrument will visualise :
DV = MV x “rot” + “OFSt”
where: DV = visualised value
MV= measured value
Example 1: It is desired that the instrument visualises the value
effectively measured at 20° but that, at 200°, it visualises a value
lower than 10° (190°).
Therefore : M1=20 ; D1=20 ; M2=200 ; D2=190
“rot” = (190 - 20) / (200 - 20) = 0,944
“OFSt” = 190 - (0,944 x 200) = 1,2
Example 2: It is desired that the instrument visualises 10° whilst the
value actually measured is 0°, but, at 500° it visualises a 50° higher
value (550°).
Therefore : M1=0 ; D1=10 ; M2=500 ; D2=550
“rot” = (550 - 10) / (500 - 0) = 1,08
“OFSt” = 550 - (1,08 x 500) = 10
By using par.
“FiL”
it is possible to
program time constant of the
software filter for the input value measured, in order to reduce
noise sensitivity (increasing the time of reading).
Using par.
“diSP”,
located in the group
“
]
PAn”,
it is possible to set
normal visualization of the display which can be the measure (dEF)
or the alarm threshold AL1, AL2 (AL1, AL2).
4.2 - PEAK VALUES MEMORIZATION AND HOLD FUNCTION
The instrument memorizes the highest and lowest peak
measurement values.
To visualize such values simply press the
UP
key to visualize the
highest peak or the
DOWN
key for the lowest peak during normal
operation of the instrument.
When the instrument is switched off, such values are always re-set.
However, it is also possible to re-set these values if the instrument
is switched on by using the U key that has been suitably
programmed (see par. U key with function "USrb" = r.Pic).
Again, using the U key it is possible to visualize the difference
between the two peaks on the display (see par. U key with function
"USrb" = d.Pic).
Besides the function of the peak values, the instrument also has a
HOLD function through which it is possible to lock the visualization
of the display on the measured value.
This function can be operated using the U key (see par. U key with
function "USrb" = Hold ).
When the HOLD function is actived, the instrument works on the
alarms in operation depending on the memorized measurement.
4.3 - ALARMS OUTPUTS FUNCTIONS (AL1, AL2)
The alarms (AL1, AL2) are depending on the process value and
before to set his functioning it’s necessary 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 relative 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).
Note:
In all the examples that follow is made reference to the alarm
AL1. Naturally the operation of the other alarms results analogous.
Have now access at the group
“
]
AL1”,
and program on par.
“OAL1”
, to which output the alarm signal has to be sent.
The alarm functioning is instead defined by parameters :
"AL1t "
- ALARM TYPE
"Ab1"
- ALARM CONFIGURATION
“AL1”
- ALARM THRESHOLD
“AL1L”
- LOW ALARM THRESHOLD (for band alarm) OR
MINIMUM SET OF AL1 ALARM THRESHOLD (for low or high
alarm)
“AL1H”
- HIGH ALARM THRESHOLD (for band alarm) OR
MAXIMUM SET OF AL1 ALARM THRESHOLD (for low or high
alarm)
“HAL1” -
ALARM HYSTERESIS
“AL1d”
- ALARM ACTIVATION DELAY (in sec.)
"AL1i"
- ALARM BEHAVIOUR IN THE EVENT OF
MEASUREMENT ERROR
"AL1t" – ALARM TYPE :
the alarm output can behave in 3
different ways.
LoAb
= LOW ALARM: The alarm is activated when the process
value goes below the alarm threshold set on parameter "AL1” and
will be deactivated when it goes above the value [AL1+HAL1]. With
this mode is possible to program the minimum and the maximum
set of “AL1” by “AL1L” and “AL1H” parameters.
L o A b
o f f
O N
A L 1
A L 1
P V
H A L 1
t i m e
o f f
o f f
O N
O U T
HiAb
= HIGH ALARM: The alarm is activated when the process
value goes higher than the alarm threshold set on parameter "AL1"
and will be deactivated when it goes below the value [AL1 - HAL1].
With this mode is possible to program the minimum and the
maximum set of “AL1” by “AL1L” and “AL1H” parameters.
H i A b
o f f
O N
A L 1
P V
t i m e
H A L 1
o f f
o f f
O N
O U T
A L 1
LHAb
= 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" and
will be deactivated when it goes below the value [AL1H - HAL1] or
when it goes above the value [AL1L + HAL1].
L H A b
O N
o f f
A L 1 H
A L 1 L
P V
t i m e
H A L 1
H A L 1
o f f
o f f
O N
O U T
A L 1
TECNOLOGIC spa - TLV 38
- OPERATING INSTRUCTIONS - Vr. 01 - ISTR 06612 - PAG. 4
