Meter servicing on-site is performed employing the "In-Line" method. The meter is
isolated and test water discharge fittings are temporarily installed. The inlet valve is opened to allow water to pass
through the subject meter and then through the test meter. The collected registration on the subject meter is
compared to the test meter to obtain an unadjusted accuracy result. The unadjusted accuracy result is amended
by the test meter accuracy factor to reach a true adjusted accuracy result. Coulter uses Sensus Metering Systems
125-W and W-1250 field testers. These units have been designed specifically for the task and feature electronic
re-settable registers providing the maximum accuracy calculations. Each service vehicle carries spare calibrated
measuring modules required in the event of an equipment failure. Test meter modules are tested and calibrated
weekly to ensure the highest standard of performance with no interruption in field service. Test flows and quantities
are pursuant to AWWA guidelines or the manufacturer’s claims, whichever is the more stringent.
Meters serviced in our shop are flow tested into measured calibration tanks employing the "gravimetric" method
whereby the water discharged into the calibration tank is weighed.
Electronic metering devices (electromagnetic flow meters etc.) are tested and verified employing the respective
manufacturers’ approved equipment. This equipment must be returned to the manufacturer annually for re-certification.
Wherever possible, in addition to the electronic testing, wet runs are performed as a secondary verification. Wet runs
are conducted using the "In-Line" method.
Where meters are equipped with contact closures or pulse outputs, while the flow test is being performed on a
registered throughput basis, a counter is employed to confirm the outputs. Similarly, where 4-20mA loops are present,
this output is checked using "Fluke Multimeter" devices.
Meter service reports are generated via an "Access" management system featuring up to 10 years history per
individual location. These are detailed reports providing before and after accuracy results, meter details, locations
and contact references. In addition, our system has a re-date field used to schedule future scheduled maintenance.
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