Calibration Check and Adjustment
The accuracy of the Recordall Turbo Series meters is tested at the factory before shipment. However, after a long period of
service, it may be necessary to recalibrate a meter. The meter can be tested for accuracy using appropriate connections with
either a test tank of known volume or a test meter. The meter can be tested in the setting by running output flow through
the optional test port, if so equipped. The Recordall Turbo Series integral calibration mechanism can be adjusted under
line pressure, simplifying and reducing calibration time. The following instructions are provided to assist in performing a
calibration check and adjustment.
Accuracy Test
IF THE OPTIONAL TEST PORT IS TO BE USED, UPSTREAM AND DOWNSTREAM VALVES MUST BE CLOSED PRIOR TO
REMOVING PLUG AND INSTALLING APPROPRIATE CONNECTIONS. FAILURE TO DO SO CAN LEAD TO PLUG BEING
EJECTED FROM HOUSING, CAUSING PERSONAL INJURY AND/OR PROPERTY DAMAGE. WHEREVER AN INSTALLATION
IS EQUIPPED WITH A DRAIN VALVE FOR METER FLUSHING, OPEN THE DRAIN VALVE TO RELIEVE PRESSURE WITHIN
THE METER. IF THE INSTALLATION DOES NOT HAVE A DRAIN VALVE, CAREFULLY LOOSEN TEST PLUG UNTIL IT BEGINS
LEAKING. STOP AND WAIT FOR PRESSURE TO BLEED DOWN, THEN CONTINUE TO SLOWLY LOOSEN, MAKING CERTAIN
THE PRESSURE IS COMPLETELY BLED OFF BEFORE REMOVING.
1. After installing the appropriate connections, test the meter by closing the downstream valve (if using integral test
port) and slowly opening the upstream valve. Slowly open the test circuit downstream valve to throttle ow for
test purposes.
2. Place a test tank of known volume at the output of the meter. An alternative is to connect a calibrated test meter to the
output. Accuracy testing requires test volumes at least as large as the register test circle.
3. As in testing the accuracy of any meter, the Recordall Turbo Series meter must rst be purged of air by running water
through the meter.
OTE:N Good test practices, such as those outlined in the AWWA M6 manual, are required to perform reliable field accuracy
tests. Register "jump" can occur in some instances if valves are abruptly opened or closed. While this jump is
not accumulative (no affects in service billing), it can affect accuracy results (1% per division on a one test circle
volumetric test).
4. Operate the meter until the test tank is lled to the calibrated level or the predetermined quantity has registered on
the calibrated test meter. Because accuracy may vary slightly with ow rate, it is recommended that the meter be
tested at low, intermediate and high ows.
5. Record the quantity registered on the meter during the test.
6. Perform the following calculations to determine meter accuracy:
(Quantity Registered on Meter)/(Test Tank or Test Meter Quantity) x 100=Meter Accuracy
Maintenance
RTS-UM-00380-EN-09Page 10 January 2015
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