Varec 7532, Installation And Operation Manual

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7532 Appendix
11.4.5 Particularities in "approved" operation
The 7500 RTG level radar is set to custody transfer mode after commissioning using a
custody locking switch (see page 36). 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 ( ).
7500 RTG radar devices continuously monitor the compliance with accuracy
requirements for custody transfer measurements according to OIML R85. If, for
example, the accuracy cannot be maintained due to quick surface movements, this is
reported via a separate alarm in the local display (displays "#" symbol) and via digital
communication.
11.4.6 Definition of terms
For definitions and procedures please refer to the following documents:
• Manual of Petroleum Measurement Standards, Chapter 3 - Tank Gauging,
Section 1.B - Standard Practice for Level Measurement of Liquid Hydrocarbons in
Stationary Tanks by Automatic Tank Gauging, American Petroleum Institute, second
edition, 2001
• OIML R 85, Organisation Internationale de Métrologie Légale, International
Recommendation R 85, edition 1998 (E)