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2.1 Pre-Installation Testing
Testing of a flow-meter before installation is a common source of mistakes that has the
possibility to permanently damage your flow-meter. Tests should always be carried out in
conditions that match the operation parameters that the meter was selected for; most
importantly flow rate and chemical compatibility. Testing of Aluminium meters on water is
not recommended however it is possible without damage so long as all of the water is
removed from the meter following the test. Aluminium meters tested on water should
always be dried after testing, as stagnant water will cause corrosion of Aluminium.
Any flow-meter which is individually calibrated at the factory will be factory marked with
its respective K-Factor (Pulses/Litre or Pulses/Gallon); there is typically no reason to carry
out any pre-installation accuracy testing on these meters. For those users that wish to
carry out pre-installation testing or calibration of a non-calibrated model, it is important
that the test procedure be carried out scientifically or the results of the test will be
meaningless. Particular cases that may benefit from field calibration or accuracy testing are
those with liquids of very low viscosity (<1cP).
For any field calibration of your flow-meter it is important to consider the accuracy of
your calibration procedure, and of your volume standard. Calibration of your flow-meter
using a volume standard of unknown accuracy will produce poor results; a bucket or
Intermediate Bulk Container (IBC) should never be used as a volume standard. Ideally your
volume standard must be large enough to contain at least 2 minutes of flow at the nominal
system flow rate, and the flow-meter should not be operated below its minimum flow-rate
at any point during the calibration run.
Never test an Oval Gear flow-meter on compressed air; to do so will cause
dry running and over speeding of bearings, leading to premature wear and
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