Wisconsin Administrative Code › Public Service Commission › Chapter PSC 134 - Standards For Gas Service › Section PSC 134.26 - Meter testing and testing equipment

Current through June 24, 2024
(1) Each public
			 utility giving gas service is responsible for the accuracy of equipment used to
			 measure service to its customers and all gas supplied by the utility shall be
			 metered unless specific exemption is obtained from the public service
			 commission. The utility shall own and maintain the equipment and facilities
			 necessary for accurately testing the various types and sizes of meters used by
			 the utility for the measurement of gas, shall make the tests required by these
			 rules, shall maintain the measuring devices, and maintain their accuracy;
			 unless arrangements are made to have the work done by others who have properly
			 equipped laboratories, are approved by the commission and arrangements are also
			 made to have equipment and procedures checked by the public service commission.
			 A test by the manufacturer of a metering device is not acceptable unless
			 witnessed by a utility representative.
(2) Each public utility giving gas service
			 shall own and maintain, except as provided in sub. (1), a meter prover of
			 sufficient capacity to test meters in accordance with s.
			 PSC
			 134.28. The meter prover shall be complete with all
			 accessories needed for accurate meter testing, shall be suitably located for
			 meter testing, and shall be protected from drafts and excessive temperature
			 changes. The equipment shall be maintained in good condition and correct
			 adjustment and be capable of determining the accuracy of service meters to
			 within one-half of one per cent. When the meter prover is used to test
			 temperature-compensating meters, there shall be present a
			 temperature-indicating device to accurately determine the temperature of the
			 prover to within + or - 1° Fahrenheit.
(3) Each public utility giving gas service
			 through turbine or rotary displacement type meters shall a) own and maintain,
			 except as provided in sub. (1), a flow or volumetric meter of suitable
			 capacity, together with necessary accessories, and it shall maintain such
			 equipment in proper adjustment so that it will be capable of determining the
			 accuracy of turbine or rotary displacement type meters to within one-half of
			 one percent; or b) have a record of tests of each turbine or rotary
			 displacement type meter made by an acceptable laboratory or by a manufacturer
			 witnessed by a representative of the utility. The record should show that the
			 test included a check of the recording device.
(4) Each public utility giving gas service
			 through orifice type meters shall own and maintain, except as provided in sub.
			 (1), instruments for checking the diameter of the orifice, a water column for
			 testing the pressure differential recorder, and a mercury column or a dead
			 weight gauge tester for testing the static pressure recorder so that the
			 utility will be capable of determining the accuracy of these orifices and
			 recorders to within one-half of one per cent.
(5) All instruments and equipment used for
			 testing of meters shall be maintained in good condition and correct adjustment
			 and be capable of determining the accuracy of service meters to within one-half
			 of one percent. Bell type provers shall be checked at least once each 3 years
			 against a standard by either the bottling or strapping method. All electrical
			 and electronic equipment associated with testing equipment shall be tested
			 every 6 months.
(6) A rotary
			 displacement type meter, when used as a standard for testing other service
			 meters, shall be given a differential test every 6 months. An original
			 differential test record of the standard meter shall be established and all
			 future differential test results shall be recorded and compared with the
			 original test record. When the test differential pressure differs from the
			 original test record by more than 25% at approximately 25% of the capacity of
			 the meter, the meter shall be cleaned and/or repaired. All associated
			 electrical equipment shall be tested before each series of tests. Associated
			 pressure and temperature correction equipment shall be tested every 6
			 months.
(7) A diaphragm-type meter
			 shall not be used as a standard for testing other service meters.
(8) The temperature in the proving and meter
			 storage rooms shall not vary by more than ±3° Fahrenheit, or testing
			 shall be stopped. If the proving equipment can compensate for a temperature
			 differential between the proving equipment and the meter, then testing may be
			 performed within the proving equipment temperature specification. The proving
			 and meter storage rooms shall be equipped with a temperature recording device.
			 A meter shall be stored in the temperature controlled area a minimum of 12
			 hours before being tested. The meter shop shall be kept in a clean and orderly
			 manner.