2-14
IM MT300-02EN
2.5 Performing Zero Calibration
Be sure to perform zero calibration (zero CAL) before making a measurement. If the environmental
conditions change while you perform continuous measurements, perform zero calibration again.
Procedure
Gauge Pressure/Differential Pressure Model
1.
Open the input to the atmosphere.
2.
Press
ZERO CAL
. Zero calibration is executed.
Absolute Pressure Model
Use of vacuum pump with a 1 Pa or higher performance.
1.
Connect the vacuum pump to the input port, and evacuate the air.
Make the tube between the vacuum pump and the instrument as short as possible to increase the degree
of vacuum.
2.
Press
ZERO CAL
. The following menu appears.
3.
Press the
Exec
soft key. Zero calibration is executed.
Zero Calibration (with offset)
Prepare a reference instrument (vacuum gauge) with the following specifications: 1 kPa abs or less
and 0.2% of reading or better.
1.
Connect the reference instrument (vacuum gauge) and the vacuum pump to the input port.
Evacuate the air to 1 kPa abs or less.
2.
Press
ZERO CAL
. The following menu appears.
3.
Press the
Exec Value
soft key. The following screen appears.
4.
Use the arrow (▲, ▼, ◄, and ►) keys to enter the input reference value.
The unit is kPa.
5.
Press
ENTER
. Zero calibration is executed.
Accuracy includes the accuracy of the reference instrument in use.
If the difference between the zero CAL value and the default value (factory default) is outside the –1 kPa to
+1 kPa range, an error occurs, and zero CAL is not executed.