Operation & Installation Manual V12-V6 2010-05-31.doc
31/05/2010
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2.4.6. Path substitution
The ALTOSONIC V12 is designed for custody transfer applications. In order to maintain the
accuracy required for custody transfer measurement under all circumstances, a minimum of
three out of five measuring paths must be operational. In case one or two of the five
measuring paths fail during operation, an automatic path substitution procedure is started.
This enables the unit to continue operation with minimum added uncertainty. Nevertheless it
is recommended to resolve the cause of the problem at the earliest opportunity
2.4.7. Write protect lock
A security lock is used to prevent unwanted changes to the flow meters configuration set-up.
It is implemented as a DIP switch, for locating this switch see Chapter 9 Marks and Seals,
Figure 9-1. Switch number 4 in position “off” means overwrite is disabled (protected), switch
number 4 in position “on” means overwrite is enabled.
During flow calibration a final correction factor has to be entered and secured. After locking
the electronics and its embedded software, only functions that will not impact on the reading
of the meter can be accessed.
2.4.8. Sealing requirements for fiscal Use
Having designed the ALTOSONIC V12 for custody transfer flow measurement mainly fiscal
applications will be monitored. In many national regulations sealing of the main flow meter
components and electronics is mandatory when using it for fiscal purposes. This prevents
altering the meter configuration without notice (see Chapter 9 Marks and Seals).
Overwriting the fiscal meter’s software parameter set-up is disabled by means of a DIP-
switch. Access to this switch is only possible by breaking a physical seal, such as e.g. a
sticker, see Chapter 9 Marks and Seals, Figure 9-1. (In addition to parameters being
password protected).
