Ruth from Seattle. Found a significant metering error this week. A large grocery store had two parallel service conductors feeding the same service entrance — both were supposed to run through the CT cores for current measurement but one conductor was routed around the CT. The demand meter was only measuring half the actual load for at least three years. This one goes in the other direction — the client was underpaying.
Demand meter installed wrong — measuring half the load for three years
Derek from Charlotte. Interesting case. Did the utility discover this on their own or did you find it?
Ruth again. I found it while trying to explain why the demand readings seemed low relative to the equipment load. Pulled the metering wiring diagram from the utility and spotted the discrepancy.
Derek again. What happens now? The utility has a right to back-bill for undercharges in most states but that right is limited — usually 2 to 3 years. You just found them more than 3 years of underbilling.
Greg from Columbus. Also check who installed the service — was it the utility or the client's contractor? If the utility made the metering error the back-billing period may be limited further. Some states limit utility back-billing to 12 months when the error was the utility's fault.
Greg the original service was installed by the utility when the store was built. The routing around the CT appears to have been an installation error by the utility's crew.
Greg again. That is your strongest argument for limiting back-billing. Document the utility's installation responsibility with any records you can find — permit records, service installation orders, anything showing the utility did the original metering work. That shifts the error responsibility to them and should cap their back-billing rights.