- -
30
Calibration of 0°C
: insert the probe in a bath at 0°C. The instrument display shows the
temperature value that it is reading: when the reading has stabilised, press <ENTER> to
confirm the point at 0°C for the reference sample probe. Press <ESC> to move on to the
second point without calibrating the first point at 0°C.
Second and third calibration point
: the instrument proposes 100.00°C as second calibration
point; if a different calibration value is necessary, change it and confirm by pressing
<ENTER>. At this point the instrument display shows the temperature value that it is reading
and the calibration value: the latter may be altered using the arrows. When the values indi-
cated by the instrument are the same as those of the reference probe, press <ENTER> to con-
firm. If you do not want to perform this step, press <ESC>. The instrument then proposes
200.00°C as third point: follow the same procedure as for the second point. Press <ENTER>
to confirm or <ESC> to cancel the current step. Calibration is now completed.
3)
View/edit parameters
: with this function it is possible to view and/or modify the coefficients that
describe the curve T=f(R) used by the programme for finding the temperature as a function of
the resistance of the PRT sensor PRT (see the appendix for details).
The following example shows how to modify the parameter R
0
of the curve of the Pt100 sensor
connected to input A of the instrument. For convenience of setting, this parameter is shown in
thousandths of an ohm, so 100,000
Ω
is indicated as 100000m
Ω
. Insert the new value and press
<ENTER> to confirm it. If you do not want to correct the value but only view it, press
<ESC/CLR> to quit without making any variations.
The other parameters of the curve (
α
,
δ
and
β
) are shown using only the significant figures of the
respective values: for example
α
= 0.00385055 is shown as 385055 since only this part of the co-
efficient can be varied. In the same way
δ
= 1.499785 is shown as 1499785 (without decimal
point) and
β
= 0.10863 as 10863.
probe connected
to input A
date of the last calibration
Select R
0
Set the desired
value then
confirm with the
<ENTER> key
5
3
1
1
0
1
2
3
4
5
7
9
6
8
4)
Copy Factory Data
: this function transfers the memorised factory calibration data into the probe.
It is useful when you notice that incorrect calibration data have entered (for example, due to in-
correctly performed calibration) and you are temporarily unable to perform a new calibration.
