Badger Meter Test Equipment - Manual (Page 2)

®
Due to continuous research, product improvements and enhancements,
Badger Meter reserves the right to change product or system specifica-
tions without notice, except to the extent an outstanding contractual
obligation exists.
Copyright © Badger Meter, Inc. 2007. All rights reserved.
Please see our website at
www.badgermeter.com
for specific contacts.
BadgerMeter,Inc.
P.O. Box 245036, Milwaukee, WI 53224-9536
(800) 876-3837 / Fax: (888) 371-5982
www.badgermeter.com
GENERAL:
The Model PSMT Portable Small Meter Tester [PSMT] is designed for
use in routine field audits of meter accuracy by comparing the meter
being tested to the known accuracy of the TEST METER in the PSMT.
The accuracy of the audit test is dependent upon following good testing
techniques, accurately recording data, and proper maintenance of the
PSMT. This unit is designed to facilitate field accuracy audits and
should not be considered a tool for certified meter testing which
requires accurate temperature, rate, and pressure control along with
calibrated volumetric or gravimetric standards. The TEST METER
includes a test tag that clearly shows the certified accuracy of the
meter installed in the PSMT. The accuracy [TEST METER Factor] of
the TEST METER is factored in audit test calculations.
INSTALLATION:
Connect the PSMT downstream in series with the meter being tested
using the hoses and adapters supplied.
NOTE: For accurate results, it is critical that the audited meter is
isolated so that all flow passes through both meters. In the event that
testing is conducted by connection of the PSMT to household plumb-
ing, ensure that no leaks are indicated in the plumbing system and that
no water is used during the tests.
Safety Considerations
· Never operate the PSMT above 100 psi.
· Secure the PSMT and hoses to prevent personal
injury from potential movement, especially at higher
operating pressures.
· Ensure proper drainage or containment of dis-
charged water to prevent water damage.
· Open and close valves in a manner to prevent water
hammer in the installation.
To prevent air entering the PSMT between test flows and to provide
backpressure through the PSMT, install the OUTLET hose so that
there is a free-air discharge into a container or waste drain at an
elevation at least 12” above the OUTLET of the PSMT. Always use
the return ell on the discharge hose end for accurate testing. Ensure
that there is sufficient volume in the wastewater container to contain
the test volumes or that a suitable drain is available.
TEST PROCEDURE:
1. Ensure that all connections are watertight, that proper water
disposal is provided, and then gradually open the supply.
2. Partially open the OUTLET valve. Then open the inlet valve
gradually, to purge all air from the PSMT, hoses, connec-
tions, and the audited meter.
3. With the water running, set the desired flow test rate by
regulating the OUTLET valve and timing the movement of
the sweep hand on the TEST METER.
4. When the flow rate is established, close the INLET valve.
5. With no flow present through the meters, set the test ring on
the TEST METER dial to zero.
6. Accurately record the INITIAL reading of the AUDITED
meter (including the test circle).
7. Open the INLET valve to start the test flow.
8. Close the INLET valve when the desired test volume is
indicated on the test meter.
9. Record the final reading on the test meter and the audited
meter.
10. One can repeat the test at this rate starting at Step 5.
For an overall audit of meter performance, tests should be conducted
at three flow rates. To ensure test reliability, two tests can be averaged
at each rate and if there is gross error between tests, additional tests
should be run – discarding the gross error. Alternately, larger test
volumes can be chosen.
ACCURACY EVALUATION:
Calculate the accuracy of the audited meter at each flow rate as
follows:
1. Subtract the INITIAL reading from the FINAL reading to
determine the volume for the TEST METER and AU-
DITED meter for each test run.
2. Compare these two values to determine whether or not
the audited meter performs within acceptable limits.
NOTE:
The test meter has a calibrated accuracy of
100% ± 1.5% over a flowrange of ½ - 25 GPM. This
must be taken into account when comparing the two
meters.
STORAGE:
When the tests are complete, turn off the water supply and store the
PSMT and accessories as follows:
1. Open the INLET and OUTLET valves to remove all
water from inside the TEST METER.
2. Disconnect the hoses and return the protective caps to
the PSMT hose connectors.
3. Disconnect all fittings, drain all of the water from the
hoses and fittings and neatly store in the nylon bag se-
cured in the cover of the PSMT.
4. Wipe away any water from the interior and exterior of the
PSMT, close and secure the cover.
NOTE: For long life and accuracy of the PSMT:
· Store and transport the PSMT where it will not be sub-
jected to freezing temperatures.
· Handle with care, the PSMT is a precision instrument.
· Keep the INLET and OUTLET valves closed when the
PSMT is not in use.
· Keep the interior surfaces dry and always drain the
water from fittings and hoses before storage.
MAINTENANCE:
The PSMT requires only proper care as outlined in the INSTALLATION
and STORAGE sections. Peroidic accuracy certification of the TEST
METER should be done to ensure the continued accurate performance
of the meter. These tests should be conducted using adapters in the
test bench which allow connection of the PSMT using the hoses
provided. The TEST METER should not be removed from the PSMT
case for testing. If the accuracy changes over time and usage, a new
TEST METER FACTOR as determined by certified testing should be
used in ACCURACY CALCULATION.