Endress+Hauser Proline Promass 83, Руководство по эксплуатации

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Proline Promass 83 FOUNDATION Fieldbus 6 Commissioning
Hauser 55
6.2.4 Gas measurement
Promass 83 is not only suitable for measuring fluid flow. Direct mass measurement based on the
Coriolis principle is also possible for measuring the flow rate of gases.
!
Note!
• Only mass and corrected volume flow can be measured and output with the gas-measurement
mode. Note that direct density and/or volume measurement is not possible.
• The flow ranges and measuring accuracy that apply to gas measurement are not the same as those
for liquids.
Function setting for gas measurement (using a FF configuration program )
1. Open the configuration program and then the Resource Block.
2. Use the WRITE_LOCK parameter to check whether hardware write protection is deactivated:
– Write protection activated = LOCKED
– Write protection deactivated = NOT LOCKED
Deactivate the write protection if necessary
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3. Open the Transducer Block.
4. Enable the programming mode:
– Enter the enable code in the “Un-/Locking - Access Code” parameter
(default = 83).
– The “Un/Locking - Access Status” parameter should now display “Unlocked Customer”.
5. Empty pipe detection has to be disabled so that measurement can be performed even at low
gas pressures. Set the “EPD - Empty Pipe Detection” parameter to OFF.
6. On account of the low mass flow involved when gas flows are measured, it is advisable not to
use a low flow cutoff. Set the “Low Flow Cutoff - Assign” parameter to OFF.
7. If the “Low Flow Cutoff - Assign” parameter was not set to “OFF”, configure the following
parameters:
“Low Flow Cutoff - On-Value”:
Flow rates for gas measurements are low, so the value for the switch-on point (= low flow cut-
off) must be correspondingly low.
Recommended setting: 0.0000 [unit]
“Low Flow Cutoff - Off-Value”:
Enter the switch-off point as a positive hysteresis in %, referenced to the switch-on point.
Recommended setting: 50%
Corrected volume measurement with gas:
Certain other parameters have to be configured if corrected volume flow (e.g. in Nm
3
/h) is to be
measured and output instead of mass flow (e.g. in kg/h). The procedure is as follows:
8. In the “System Unit - Cor. Volume Flow” parameter, select the engineering unit for the cor-
rected volume flow.
9. In the “System Unit Reference Density” parameter, select the engineering unit for reference
density.
10. Set the “Reference Param. - Cor. Volume Calc.” parameter to “Fix. Ref. Density”.