Endress+Hauser Micropilot S FMR531, Руководство по эксплуатации

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Micropilot S FMR531 with HART/4...20 mA Appendix
E Hauser 93
Integration into the Asset Management System
The HART interface allows the integration into the AMS® (Asset Management System) from Fisher-
Rosemount.
11.3.3 Custody transfer mode
Micropilot S is a weight and measure approved level transmitter. Either the innage or the ullage can
be selected as the custody transfer variable.
The selected variable is the basis for the subsequent calculation of the current amount of product in
a tank, along with other measured variables such as (average) temperature and pressure.
This opens up numerous application options in custody transfer:
• Quantity calculation of mineral oils
• Quantity calculation of alcohols
11.3.4 Weight and measure approval, Standards Authorities approval,
Compulsory reapproval
The type approvals for custody transfer issued by the PTB and NMi, a copy of which is enclosed
with every device, prove the fundamental suitability of the various types for custody transfer.
In addition to this, the accuracy of every single device is documented using a calibration certificate,
which is issued in the factory after the device has been tested on a reference test rig.
On request, a separate Initial verification of the devices can be carried out with a National Standards
Authorities inspector present, who issues a preliminary test certificate for every device. In the initial
verification, the device is tested to ensure that it complies with the limit of error in legal metrology ,
which lies at +-2mm for radar measuring devices in Germany.
Essentially, this proves that the devices are weight and measure approved . The devices must not,
however, be used in custody transfer mode straight away.
The measuring device is not approved until after the approval after installation by the Standards
Authorities. For this, the device's level measurement is compared with the tank gauging by a
National Standards Authorities inspector using manual dips (also "Initial verification"). As a rule, a
quiescent tank gauging is dipped by hand three times in a row and then compared with the value
displayed by the level radar. Depending on national regulations, the transfer error limit, calculated
as the arithmetic mean of the absolute deviations of all three measurements, must not exceed
double the limit of error in legal metrology (compare, for example, the German "Eichordnung" or
the American "API 3.1B", in which the necessary procedures are also defined).
Depending on national regulations, this test is repeated with various tank gaugings. Using
linearisation tables to compensate any non-linearities that occur in measurement is permitted. For
this, the Micropilot S level radar offers a special dip table, compare
→
Chap. 6.5.
After the measurement has been approved by an inspector, he seals the level radar at the stamp
position and thereby also secures the programming status of the device.
Those operating an approved level transmitter are obligated to obtain reapproval in accordance
with the applicable national regulations from the Standards Authorities.
11.3.5 Particularities in "approved" operation
The Micropilot S level radar is set to custody transfer mode after commissioning using a custody
locking switch (see Page 32) The position of the custody locking switch is secured and sealed using
the sealing pin.
During custody transfer measurement, all custody transfer-relevant functions for operation are
automatically locked, so that the device software can not be used, either via local operation or via
digital communication settings. This locked status is displayed by the key symbol (
).