Indiana Administrative Code › Title 170 - INDIANA UTILITY REGULATORY COMMISSION › Article 4 - ELECTRIC UTILITIES › Rule 1 - Standards of Service › Section 1-10 - In-service tests; watthour meters, self-contained

Current through July 10, 2024
Authority: IC
				  8-1-1-3;
				  IC
				  8-1-2-4
Affected: IC
				  8-1-2-35
Sec. 10.
(a) A
				utility may adopt either Method A as described in subsection (b) or Method B as
				described in subsection (c) for maintaining the accuracy of self-contained
				meters without attachments or with frictionless attachments.
(b) For Method A, periodic testing of
				watthour meters, each public utility shall, after the adoption of this rule,
				use not more than a sixteen (16) year schedule of periodic testing.
(c) For Method B, quality control testing of
				watthour meters, a public utility may adopt the following quality control
				testing method for self-contained watthour meters, in service, on written
				notice to the commission:
(1) Meters shall be
				divided into homogenous groups.
(2)
				The meters in each group may be further subdivided into lots; however, no lot
				size shall be less than three hundred one (301) meters.
(3) From each lot there shall be drawn
				annually a number of meters to be tested as specified in Table A-2, ANSI/ASQC
				Standard Z1.9, dated 1993, using Inspection Level II. Due care shall be
				exercised that the meters to be tested shall be drawn at random, and all such
				meters shall be tested for accuracy.
(4) The test criterion for acceptance or
				rejection of each lot shall be based on the test at full load only and shall be
				that designated for Double Specification Limit-Variability Unknown-Standard
				Deviation Method at the 2.50 Acceptable Quality Level (normal inspection) as
				shown in Table B-3, ANSI/ASQC Standard Z1.9, dated 1993.
(5) The necessary calculations shall be made
				in accordance with the illustration (Example B-3), ANSI/ASQC Standard Z1.9,
				dated 1993. The upper and lower accuracy specification limits, U and L, shall
				be one hundred two percent (102%) and ninety-eight percent (98%),
				respectively.
(6) A lot shall be
				rejected if the total estimated percent defective (p) exceeds the appropriate
				maximum allowable percent defective (m) as determined from Table B-3, ANSI/ASQC
				Standard Z1.9, dated 1993.
(7)
				Meters in a rejected lot shall be subject to an accelerated test schedule to be
				completed within a maximum period of ninety-six (96) months and shall comply
				with section 9 of this rule, or shall be retired from service. Such accelerated
				testing of a rejected lot may be discontinued when the subsequent test results
				show that the lot is within acceptable limits of accuracy.
(8) A public utility, operating under this
				optional testing plan, may elect to test the meters included in any group or
				lot on a test schedule of not more than sixteen (16) years subject to section 9
				of this rule.
(9) Each public
				utility shall keep all necessary records to enable the commission to check
				procedures followed, tests made, and calibrations employed in conformance with
				this optional testing method.
(10)
				All provisions of the aforesaid ANSI/ASQC Standard Z1.9, dated 1993,
				explanatory of or essential to the application of Table A-2, Table B-3, and
				Example B-3, as referenced in subdivisions (3) through (5), are hereby
				incorporated in this rule by reference.