Statutes, codes, and regulations
California Code Of Regulations
Title 4 - Business RegulationsDivision 9 - Division of Measurement Standards, Department of Food and AgricultureChapter 1 - Tolerances and Specifications for Commercial Weighing and Measuring Devices
Article 2.2 - Electric Watthour Meters
Section 4027.4 - T. Tolerances

Cal. Code Regs. tit. 4 § 4027.4

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Current through Register 2024 Notice Reg. No. 50, December 13, 2024
Section 4027.4 - T. Tolerances
T.1. Meters with Separate Components. Where instrument transformers or other components are used, the provisions of this section shall apply to all metering components.
T.2. Meter Creep Test.
T.2.1. (EM) The meter indicator or display shall not change by more than one least significant digit with the voltage circuit(s) energized and current circuit(s) not energized for a duration of one hour using the watthour test constant (Kt) output indications.
T.2.2. (MM) A meter rotor shall rotate no more than one complete revolution in 10 minutes with the meter voltage circuit(s) energized and the current circuit(s) not energized.
T.3. Meter Starting Load Test.
T.3.1. (EM) The watthour test constant (Kt) output indication shall continue to advance when a load of 0.5 amperes is applied.
T.3.2. (MM) The meter rotor shall rotate continuously when a load of 0.5 amperes is applied.
T.4. Application to Underregistration and to Overregistration. The following prescribed tolerances shall be applied to errors of underregistration and errors of overregistration.
T.4.1. Tolerance Values. Maintenance and acceptance tolerances for electric watthour meters shall be as follows for full and light load tests:
(a) Maintenance tolerance shall be 2 percent for full and light loads.
(b) Acceptance tolerance shall be 1 percent for full and light loads.
T.4.2. Power Factor Tests. Power factor tests shall be conducted at 0.5 power factor setting:
(a) Maintenance tolerance shall be 2 percent for full and light loads.
(b) Acceptance tolerance shall be 1 percent for full and light loads.

NOTE: 0.5 power factor light load tests shall be conducted at 20 percent of the Test Amperes (TA).

Cal. Code Regs. Tit. 4, § 4027.4

1. Amendment deleting asterisks filed 11-1-94; operative 12-1-94 (Register 94, No. 44).
2. Repealer and new section filed 1-13-2009; operative 2-12-2009 (Register 2009, No. 3).

Note: Authority cited: Sections 12027 and 12107, Business and Professions Code. Reference: Section 12107, Business and Professions Code.

1. Amendment deleting asterisks filed 11-1-94; operative 12-1-94 (Register 94, No. 44).
2. Repealer and new section filed 1-13-2009; operative 2-12-2009 (Register 2009, No. 3).