© 2021 VPInstruments | MAN-VP-VP38-EN | Revision: 2100 | Date: 25-01-2021
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6
Mechanical installation
6.1
Installation point
The installation point is crucial for a correct measurement. Sources of error can be: installation
effects, unknown flow profiles, swirls, pressure and temperature effects, humidity effects, oscillations
in the flow, etc. To ensure the highest possible accuracy of flow measurement, the installation and
piping instructions must be followed. Therefore read this paragraph carefully.
Take into account:
Choose a location which is accessible, which allows access for wiring and maintenance activities.
Meet the specifications of the VPFlowScope In-line 3/8" flow meter. When the specifications are
not met, for instance the pressure or temperature level is too high; this will cause inaccurate flow
measurement and can even damage your flow meter.
Do not apply mechanical stress on the VPFlowScope In-line 3/8" flow meter.
Avoid:
Excessive heat, check the temperature specifications
Corrosive atmosphere where possible
Electrical problems (high voltage/ high power)
Mechanical vibration and danger (walking bridges, fork lift trucks)
Any environmental source of potential error
Stop: These devices are only for use with air, oxygen and other non hazardous and non
combustible gases. The maximum working pressure is 10 bar (145 psi)
For compliance with oxygen systems, please strictly follow the safety guidelines as
provided by national laws and/or internal guidelines on use of oxygen equipment.
6.2
Piping table
Check the piping table below and match it for your application. The table shows the amount of
upstream and downstream length depending on the installation. If applicable in front of the meter, use
given upstream length. If applicable behind the meter, use given downstream length. Gas flow in
pipes follows certain rules, which must be observed for optimal measurement results. In some cases
the upstream length needs to be longer, in other cases it can be shorter.
If possible, you can always choose a longer upstream length, as these are minimum
values. The up- and downstream lengths are used industry wide as guidelines, but will
never be a guarantee for obtaining the “true value”.
