Endress+Hauser Proline Prowirl 72, Руководство по эксплуатации

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Proline Prowirl 72 11 Description of device functions
E Hauser 73
11.2.2 Group SYSTEM UNITS
Function description SYSTEM UNITS
MEASURING UNIT TYPE Use this function to specify the type of unit the measuring device should use to output
the flow.
The following types of units are available:
• Volumetric flow (volume flow)
The device measures the volumetric flow; no other calculation is carried out.
• Calculated mass flow
The calculated mass flow is calculated using the measured volume flow and the value
entered in the OPERATING DENSITY function (see Page 95).
• Calculated corrected volume flow
The corrected volume flow is calculated using the measured volume flow and the ratio
between the values entered in the OPERATING DENSITY function (see Page 95) and
in the REFERENCE DENSITY function (see Page 96).
!
Note!
The “calculated mass flow” and “calculated corrected volume flow” unit types are
calculated with fixed values (specified OPERATING DENSITY and REFERENCE
DENSITY). For this reason
only select these types of units if the process conditions are
known and do not change.
If the process conditions are not known or if the process conditions are subject to change,
we recommend you use a flow computer (e.g. Compart DXF 351 or RMC 621). Even
when the process conditions change, these flow computers can calculate the flow
correctly by means of pressure and temperature compensation.
Options:
VOLUME FLOW
CALCULATED MASS FLOW
CORRECTED VOLUME FLOW (calculated)
Factory setting:
See parameter printout supplied (the parameter printout is an integral part of these
Operating Instructions)
!
Note!
If the type of unit is changed, you are asked whether the totalizer should be reset to 0.
The new type of unit is only accepted if you confirm this message with yes. If the
message is not confirmed, the measuring system continues working with the type of unit
previously active.