Aalborg DFM Digital - Manual (Page 37)

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!11,MR,133[CR] - reads EEPROM address 133
!11,MW,133,3450[CR] - writes new sensor value (3450 counts) in to the index 133
Once 100% F.S. calibration is completed user can proceed with calibration for
another 9 points of the linearization table using the same approach.
Note: It is recommended to use Aalborg
7 supplied calibration and
maintenance software for gas table calibration. This software includes
an automated calibration procedure which may radically simplify
reading and writing in to the EEPROM linearization table.
7.3 Analog output Calibration of DFM
Mass Flow Meters
DFM series Mass Flow Meters are equipped with calibrated 0-5 Vdc (0-10 Vdc
optional) and 4-20 mA output signals. The set of the jumpers (J2, J3, J4) on the
analog printed circuit board is used to switch between 0-5 Vdc, 0-10 Vdc or 4-20
mA output signals (see APPENDIX IV).
Note: All analog outputs available on the DFM Digital Mass Flow
Meter were calibrated at the factory for the specified gas and full scale
flow range (see device front label). There is no need to perform analog
output calibration unless the analog PC board was replaced or off
set/span adjustment is needed. Any alteration of the analog output
scaling variables in the Gas independent table will void calibration
warranty supplied with instrument!
Note: It is recommended to use the Aalborg
7 supplied calibration and
maintenance software for analog output calibration. This software
includes an automated calibration procedure which may radically
simplify calculation of the offsets and spans variables and reading and
writing in to the EEPROM table.
The DFM analog output calibration involves calculation and storing of the offset
and span variables in to the EEPROM for each available output. The 0-5 Vdc and
0-10 Vdc outputs have only scale variable and 20 mA outputs have offset and scale
variables. The following is a list of the Gas independent variables used for analog
output computation:
,
,
,