R746-310-3. Meters and Meter Testing

  A. Reference and Working Standards

  1. Reference standards -- Utilities having 500 or more meters in service shall have a high grade reference standard meter which shall be calibrated at least annually by the U.S. Bureau of Standards or a testing agency that regularly calibrates with them. Other utilities with meters in service shall at least have access to another utility's or testing agency's high grade reference standards that are periodically calibrated.

  2. Working standards -- Utilities furnishing metered service shall provide for, or have access to, high grade testing instruments, working standards, to test the accuracy of meters or other instruments used to measure electricity consumed by its customers. The error of accuracy of the working standards at both light load and full load shall be less than one percent of 100 percent of rated capacity. This accuracy shall be maintained by periodic calibration against reference standards.

  B. Meter Tests -- Unless otherwise directed by the Commission, the requirements contained in the 2014 edition of the American National Standards for Electric Meters Code for Electricity Metering, ANSI C12.1-2014, incorporated by reference, shall be the minimum requirements relative to meter testing.

  1. Accuracy limits -- After being tested, meters shall be adjusted to as near zero error as practicable. Meters shall not remain in service with an error over two percent of tested capacity, or if found to register at no load.

  2. Before installation -- New meters shall be tested before installation. Removed meters shall be tested before or within 60 days of installation.

  3. Periodic -- In-service meters shall be periodically or sample tested.

  4. Request -- Upon written request, utilities shall promptly test the accuracy of a customer's meter. If the meter has been tested within 12 months preceding the date of the request, the utility may require the customer to make a deposit. The deposit shall not exceed the estimated cost of performing the test. If the meter is found to have an error of more than two percent of tested capacity, the deposit shall be refunded; otherwise, the deposit may be retained by the utility as a service charge. Customers shall be entitled to observe tests, and utilities shall provide test reports to customers.

  5. Referee -- In the event of a dispute, the customer may request a referee test in writing. The Commission may require the deposit of a testing fee. Upon filing of the request and receipt of the deposit, if required, the Commission shall notify the utility to arrange for the test. The utility shall not remove the meter prior to the test without Commission approval. The meter shall be tested in the presence of a Commission representative, and if the meter is found to be inaccurate by more than two percent of rated capacity, the customer's deposit shall be refunded; otherwise, it may be retained.

  C. Bill Adjustments for Meter Error --

  1. Fast meter -- If a meter tested pursuant to this section is more than two percent fast, the utility shall refund to the customer the overcharge based on the corrected meter readings for the period the meter was in use, not exceeding six months, unless it can be shown that the error was due to some cause, the date of which can be fixed. In this instance, the overcharge shall be computed back to, but not beyond that time.

  2. Slow meter -- If a meter tested pursuant to this section is more than two percent slow, the utility may bill the customer for the estimated energy consumed but not covered by the bill for a period not exceeding six months unless it can be shown that the error was due to some cause, the date of which can be fixed. In this instance, the bill shall be computed back to, but not beyond that time.

  3. Non-registering meter -- If a meter does not register any usage, the utility may bill the customer for the estimated energy used but not registered for a period not exceeding three months.

  4. Incorrectly-registering meter -- If a meter registers usage, but fails to register the correct amount of electric power or energy used by the customer for any reason, other than as described in Subsection R746-310-3(C)(1) and (2), the amount of such use will be estimated by the utility from the best available information, and billed for a period not exceeding twenty-four months.

  D. Meter Records -- Utilities shall maintain records for each meter until retirement. This record shall contain the identification number; manufacturer's name, type and rating; each test, adjustment and repair; date of purchase; and location, date of installation, and removal from service. Utilities shall keep records of the last meter test for every meter. At a minimum, the records shall identify the meter, the date, the location of and reason for the test, the name of the person or organization making the test, and the test results.