PSC 113.0816(2)(2) Systems and devices used by the utility to control customer metering and loads shall be tested or checked on installation and periodically thereafter, if necessary, to verify proper operation.

PSC 113.0817(1)(1) Metering facilities located at any point where energy may flow in either direction and where the quantities measured are used for billing purposes shall consist of meters equipped with ratchets or other devices to prevent reverse registration and be so connected as to separately meter energy flow in each direction. Reverse meter registration is permitted for installations with customer-owned generators served under a net billing energy rate through one meter in accordance with s. PSC 113.0926.

PSC 113.0817(2)(2) Reactive metering shall not be employed for determining average power factor where energy may flow in either direction or where the customer may generate an appreciable amount of his or her requirements at any time unless suitable directional relays and ratchets are installed to obtain correct registration under all conditions of operation and unless the general plan of installation is approved by the commission.

PSC 113.0818PSC 113.0818 Determination of average meter error. Whenever a metering installation is found upon any test to be in error by more than 2% at any test load, the average error shall be determined in one of the following ways:

PSC 113.0818(1)(1) If the metering installation is used to measure a load which has practically constant characteristics, such as a street-lighting load, the meter shall be tested under similar conditions of load and the accuracy of the meter “as found” shall be considered as the average accuracy.

PSC 113.0818(2)(2) If a single-phase metering installation is used on a varying load, the average error shall be the weighted algebraic average of the error at light load and the error at heavy load, the latter being given a weighting of 4 times the former.

PSC 113.0818(3)(3) If a polyphase metering installation is used on a varying load, the average error shall be the weighted algebraic average of its error at light load given a weighting of 1, its error at heavy load and 100% power factor given a weighting of 4 and at heavy load and 50% lagging power factor given a weighting of 2.

PSC 113.0818(4)(4) If a load, other than the light, heavy and low power-factor load specified for routine testing, is more representative of the customary use of the metering equipment, its error at that load should also be determined. In this case the average error is to be computed by giving the error at such load and power factor a weighting of 3 and each of the errors at the other loads (light, heavy and 50% lagging power factor) a weighting of 1. Each error shall be assigned its proper sign.

PSC 113.0901(1)(1) The test of any unit of metering equipment shall consist of a comparison of its accuracy with a standard of known accuracy by a qualified person. Units not properly connected or not meeting the accuracy or other requirements of ss. PSC 113.0811, 113.0812 and 113.0813 at the time of test shall be reconnected and/or rebuilt to meet such requirements and adjusted to within the required accuracy and as close to 100% accurate as practicable or their use discontinued.

PSC 113.0901(2)(2) Each unit of metering equipment shall be inspected for mechanical and electrical faults whenever the accuracy of the device is checked.

PSC 113.0901(3)(3) Each meter tested shall have the register and the internal connections checked before the meter is first placed in service and whenever the meter is repaired.

PSC 113.0901(4)(4) Each meter shall have the connections to the customer’s circuits, the disc rotation and any multiplier checked when the meter is installed or removed or an instrument transformer is changed.

PSC 113.0901(5)(5) Polyphase meters shall be tested for accuracy at 50% power factor before first being used for measuring customer’s service either by a test of each meter or by a sample test plan approved under s. PSC 113.0911 (1) (a).

PSC 113.0901(6)(6) The connections, phase sequence and multiplier of polyphase transformer-rated metering installations shall be checked for error by qualified personnel within 60 days after the meter is installed.

PSC 113.0901(7)(7) Special control devices, switches, etc., for time-of-use service shall be checked for proper operation whenever the associated meter is tested.

PSC 113.0902(1)(1) Each utility shall maintain sufficient laboratories, meter testing shops, secondary standards, instruments and facilities to determine the accuracy of all types of meters and measuring devices used by the utility. A utility may, however, with the approval of the commission, have all or part of the required tests made or its portable testing equipment checked by the original equipment manufacturers, another utility, or testing agency having adequate and sufficient testing equipment to comply with these rules.

PSC 113.0902(2)(a)(a) One or more portable standard watthour meters of capacity and voltage range adequate to test all watthour meters used by the utility.

PSC 113.0902(2)(b)(b) Portable indicating instruments of such various types as are required to determine the accuracy of all instruments used by the utility.

PSC 113.0902(2)(c)(c) One or more secondary standards to check each of the various types of portable standard watthour meters used for testing watthour meters. Each secondary standard shall consist of either an approved portable standard watthour meter kept permanently at one point and not used for field work, or not less than three approved watthour meters connected with current coils in series and voltage coils in parallel and kept running by connecting a 10-watt load. These meters must be well compensated for both classes of temperature errors, practically free from errors due to ordinary voltage variations and free from erratic registration due to any cause.