Endress+Hauser Proline Prowirl 72, Operating Instructions Manual

Page: 96 / 114

11 Description of device functions Proline Prowirl 72
96 E Hauser
REFERENCE DENSITY
!
Note!
This function is not available unless the CORRECTED VOLUME FLOW option was
selected in the MEASURING UNIT TYPE function.
Use this function to enter a fixed value for the density at reference/standard conditions.
This value is used to calculate the corrected volume flow (see MEASURING UNIT TYPE
function on Page 73).
User input:
5-digit floating-point number
Factory setting:
See parameter printout supplied (the parameter printout is an integral part of these
Operating Instructions)
!
Note!
• The appropriate unit is taken from the UNIT DENSITY function (see Page 74).
• If the selection is changed in this function, you are asked whether the totalizer should
be reset to 0. We recommend you confirm this message and reset the totalizer.
OPERATING
TEMPERATURE Use this function to specify a fixed value for the process temperature.
!
Note!
• The sensor (measuring pipe and bluff body) expands differently depending on the
existing process temperature. This has a proportional effect on the accuracy of the
measuring system since the device was calibrated at a fixed calibration temperature of
20 °C (293 K). However, this effect on the current measured value and the internal
totalizer can be compensated by entering an average process temperature in this
function.
• If the process temperature is subject to severe changes, we recommend you use a flow
computer (e.g. RMC 621 or RMS 621). These flow computers can compensate the
effect on the K-factor by means of temperature compensation. If a flow computer is
used, the value of the factory setting (20°C, 293.16 K, 68 °F, 527.67 R) must be
specified in this function.
User input:
5-digit floating-point number
Factory setting:
20°C / 293.16 K / 68 °F / 527.67 R
!
Note!
The appropriate unit is taken from the UNIT TEMPERATURE function (see Page 75).
"
Caution!
This setting does not change the permitted temperature range of the measuring system.
Please pay particular attention to the temperature application limits specified in the
product specification (see Page 63).
Function description PROCESS PARAMETER