Michigan Administrative Code
Department - Licensing and Regulatory Affairs
Public Service Commission
Technical Standards For Gas Service
Part 5 - METERS METERING EQUIPMENT INSPECTIONS AND TESTS
Section R. 460.2354 - Accuracy of metering equipment; tests; standards

(1) A utility shall use the applicable provisions of the standards adopted by reference in R 460.2344 as criteria of accepted practice in testing meters.

(2) Metering equipment must be tested by comparison with the standards that are adopted by reference in R 460.2344.

(3) A gas service meter that is repaired or removed from service for any cause must, before installation, be tested and adjusted to be correct within 1% fast or 1% slow.

(4) Every diaphragm-type gas meter must be tested before installation and adjusted, if required, to a meter accuracy of 100% plus or minus 1% at a low flow rate and at a high flow rate so that the numerical difference between the meter accuracy at these 2 flow rates is not more than 1 percentage point. A low flow rate is a flow at 20% to 50% of the rated capacity of the meter. A high flow rate is a flow at 80% to 120% of the rated capacity of the meter. The average meter accuracy of a diaphragm-type meter must be defined as 1/2 the sum of the meter accuracy at the low flow test and at the high flow test.

(5) All recording-type meters or associated instruments that have a timing element that serves to record the time at which the measurement occurs for billing purposes must be adjusted at intervals of not more than 2 years so that the timing element is not in error by more than plus or minus 4 minutes in 24 hours, under laboratory conditions, as set forth in ANSI B109.1-2019, "Diaphragm Type Gas Displacement Meters, Under 500 Cubic Feet per Hour Capacity", which is adopted by reference in R 460.2344, or by more than plus or minus 10 minutes in 24 hours under field conditions.