Section 134.26. Meter testing and testing equipment.

 

(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.

History: Cr. Register, February, 1959 . No. 38, eff. 3-1-59; am. (2), Register, January, 1965, No. 109 , eff. 2-1-65.; am. (3) and (5), cr. (6) and (7), Register, April, 1969, No. 160 , eff. 5-1-69; am. (2) and (5), cr. (8), Register, November, 1989, No. 407 , eff. 12-1-89.