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9.3 Calibration of the reference resistors
Use following procedure for recalibration of the internal reference resistors:
1.
Select the menu reference resistors.
2.
Enter the date format as YYMMDD.
3.
Connect the two reference resistors to the sensor inputs as shown on the figure
section 5.2.1.
4.
Enter the value of the two reference resistors.
Determine new resistors
Current maximum resistor : 360.000 Ohm
Current minimum resistor :
0.000 Ohm
Default resistors for DTI (0.0 Ohm & 360.0 Ohm)
No
Enter reference resistor value in sensor input 1 :
55.0000
Ohm
Enter reference resistor value in sensor input 2 : 355.0000
Ohm
< ESC > aborts, Press < Enter > to accept
The default selection should only be used if the previous calibration went wrong.
Now the calibration will show the determination of the internal reference resistors calculated
from the two connected input values:
Calculated resistor
New maximum resistor value :
360.0180
New minimum resistor value :
49.9975
< ESC > aborts, Press < ENTER > to accept
5.
Press <ENTER> when the reading is stable (±0.0005
Ω
).
6.
Confirm the taken sample by pressing <ENTER> again. If the taken sample is at the
limit of the stability criteria press <ESC> to make a new.
7.
When the calibration is finished the software downloads the new reference resistor
values to the DTI which will take about 1 second.
8.
Check the reading of the connected references in measure menu or the display.
The values must not differ more than ±0.001
Ω
for the calibration to be accepted.
