(A) Equipment and Facilities. The Corporation shall provide or have available such standard meters, instruments and other equipment and facilities as may be necessary to make the tests set forth in these rules.
(B) Reference Standards. The Corporation shall provide or have available suitable indicating electrical instruments, watt meters and watt hour meters (hereinafter called "reference standards") as may be necessary for testing the accuracy of watt hour meters. The reference standard may be a service type watt hour meter. Reference standards of all kinds shall be tested and adjusted, if necessary, at least once every two years by a recognized standardizing laboratory.
(C) Portable Standards. All portable watt hour meter standards shall be checked against the corresponding reference standards as often as may be necessary to give reasonable assurance that the errors will not change enough between successive calibrations to materially affect the results of measurements involving their use. If such check shows any portable watt hour meter standard to be in error more than one percent (1%) plus or minus, at any load at which the standard will be used, the standard shall be tested, adjusted and certified in an approved laboratory. Each portable watt hour meter standard shall at all times be accompanied by a certificate or calibration card, signed by the proper authority, giving the date when it was last certified.
(D) Portable Indicating Instruments. All portable indicating electrical testing instruments, such as voltmeters, ammeters and watt meters, when in regular use in testing purposes, shall be checked against suitable reference standards as often as may be necessary to give reasonable assurance that the errors will not change enough between successive calibrations to materially affect the results of measurements involving their use, and if found appreciably in error at zero of more than one percent (1%) of full scale value at commonly used scale deflection shall, unless calibration correction is used, be adjusted and certified in some approved laboratory.
(E) Records of Certification and Calibration. Records of certification and calibration shall be kept on file.