02/2014
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The JP8/JP9 jumpers define the Pt 100 input configuration as a 2-wire, 3-wire or 4-core circuit. For the
resistance measurement, too, only one valid set of parameters can be stored in the MTP200. For this reason
you should carry out recalibration after every change in the Pt 100 input configuration whenever maximum
accuracy is required.
Every calibration has to take place in 2 steps. The calibration points can be freely selected within the
characteristic curve range available, but we recommend that you place the calibration points within the
measuring range for a high degree of accuracy. For the 1st calibration procedure the Pt 100 simulator at the
MTP200 input is set to the desired temperature value, and the command to
Read
in is triggered. The
messages
Measurement running
and
finished
appear one after the other in the mask. After
acknowledgement with OK the 1st calibration value is accepted and shown analogously as a bar in the mask.
The proportional representation in the bar chart serves as a check and helps to avoid calibration errors.
Same calibration values for the 1
st
and 2
nd
calibration point
same bar lengths
no
measured value illustration possible
output jumps!
Next, the second calibration point is simulated with the measuring input mA value, confirming calibration with
Read
and finalized with
OK
.
For monitoring the supply circuits at the contacts d/z30 and d/z32 a reference level at 20mA is needed, which
can be simulated easily with a current sink. The voltage value is recorded by clicking the button
Read
and is
figured in bar units for monitoring.
Finally the calibration values needs to be transferred to the MTP200. Therefor mark the box
Overwrite
calibration values?
with a cross and click the button
MTP program
. The transfer starts and the question
Existing parameters will be overwritten. Continue anyway?
appears in the screen. This procedure is
started with
OK
and the next message reads:
Transferring parameters
. A final OK completes the procedure
and the calibration.
May be implemented only
for the actualization of the
calibration parameters
contained in the MTP200!
Before beginning of the
calibration the parameters
from the MTP200 must be
read in!
