Aalborg DFM Digital User Manual
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7.3.2 Gas flow 0-5 Vdc analog output calibration
1.
Install jumpers J2 on the analog PC board for 0-5 Vdc output (see Table VI).
2.
Connect a certified high sensitivity multi meter set for the voltage
measurement to the pins 2 (+) and 15 (-) of the 25 pins D connector.
3.
Write 4000 counts to the DAC channel 1: !11,WRITE,1,4000[CR]
4.
Read voltage with the meter and calculate:
5.
Save FlowOutScaleV in to the EEPROM: !11,MW,26,X[CR]
Where: X - the calculated FlowOutScaleV value.
7.3.3 Gas flow 4-20 mA analog output calibration
1. Install jumpers J2 on the analog PC board for 4-20 mA output (see Table VI).
2.
Connect a certified high sensitivity multi meter set for the current
measurement to pins 2 (+) and 15 (-) of the 25 pins D connector.
3.
Write 4000 counts to the DAC channel 1: !11,WRITE,1,4000[CR]
4.
Read current with the meter and calculate:
5.
Write zero counts to the DAC channel 1: !11,WRITE,1,0CR]
6.
Read offset current with the meter and calculate:
7. Save FlowOutScale_mA in to the EEPROM:
!11,MW,27,Y[CR]
Save FlowOutOffset_mA in to the EEPROM:
!11,MW,28,Z[CR]
Where:
Y - the calculated FlowOutScale_mA value.
Z - the calculated FlowOutOffset_mA value.
7.3.4 Gas temperature 0-5 Vdc analog output
calibration (DFM 27/37/47)
1. Install jumpers J3 on the analog PC board for 0-5 Vdc output (see Table VI).
2.
Connect a certified high sensitivity multi-meter set for the voltage
measurement to the pins 3 (+) and 16 (-) of the 25 pin D connector.
3.
Write 4000 counts to the DAC channel 2: !11,WRITE,2,4000[CR]
4.
Read voltage with the meter and calculate: