29
Adjustment and Calibration
Pressure
The pressure transducer has no nonlinear drift so an adjustment is normally not necessary.
Use the tare function to balance the pressure transducers environmental pressure change drift.
The pressure channel is adjusted using 7 sampling points. This improves the accuracy of the pressure
measurement, because it recalculates slightly nonlinearities of the pressure transducer. The order of the
adjustment points starts with point 1 and is preassigned. The value range of each point is restricted by
boundaries.
Apply the pressure values to the instruments pressure transducer inlet as shown in the table below. Adjust the
value of your reference or standard to the HDM using the navigation keys
and
. It is mandatory
to wait until the measuring value becomes stable. After the measuring value finally becomes stable the
adjustment point can be applied using the navigation key
. The instrument jumps immediately to the
next adjustment point, so the procedure can be repeated. After the last adjustment point has been applied the
instrument displays "ADJ OK" in the upper line of its display. If the adjustment is not correct, the instrument
displays "ADJ ERR" in the display along with a long warning beep. In this case the adjustment values will be
discarded and the procedure has to be started from the beginning. A failed adjustment can also be an
outcome of a defective instrument.
All HDM97 versions except BH.
Point
Display
Pressure
Input Limits
1.
"PR1"
-500 mmHg
±10 mmHg
2.
"PR2"
-250 mmHg
±10 mmHg
3.
"PR3"
0 mmHg
±10 mmHg
4.
"PR4"
150 mmHg
±10 mmHg
5.
"PR5"
300 mmHg
±10 mmHg
6.
"PR6"
900 mmHg
±10 mmHg
7.
"PR7"
1500 mmHg
±10 mmHg
All versions HDM97BH.
Point Display
BH5
BH15
BH30
BH50 BH100
Input Limits
1.
"PR1"
250
750
1500
2500
5000
±10 mmHg
2.
"PR2"
200
600
1200
2000
4000
±10 mmHg
3.
"PR3"
150
450
900
1500
3000
±10 mmHg
4.
"PR4"
100
300
600
1000
2000
±10 mmHg
5.
"PR5"
50
150
300
500
1000
±10 mmHg
6.
"PR6"
0
0
0
0
0
±10 mmHg
7.
"PR7"
-125
-250
-250
-250
-250
±10 mmHg
8.
"PR8"
-250
-500
-500
-500
-500
±10 mmHg