Working with a large retail client in Albuquerque that just got switched to PNM's new smart meters last month. The 15-minute interval data is showing some really questionable readings - lots of negative demand values during mid-day hours and some intervals with demand readings over 500 kW when the facility's main breaker is only 400A at 480V. The billing seems unaffected so far but I'm worried about future demand charges if these bogus readings get used. Anyone else dealing with PNM's new meter rollout issues?
PNM Smart Meter data quality issues - New Mexico
Marcus - negative demand readings are usually a sign of CT polarity issues or incorrect meter programming. With a brand new meter installation, I'd suspect the installer wired the current transformers backwards or the meter configuration doesn't match the actual CT ratios. The over-limit readings could be related to the same problem. You should definitely get PNM out there to verify the installation before those bogus peaks start affecting bills.
Tina you're absolutely right about the CT issues. I had PNM send a tech out yesterday and they found two phases with reversed current transformers plus the meter was programmed for 200:5 CTs when the actual installation is 800:5. No wonder the readings were garbage! They're fixing it today and will recalculate any affected billing. Thanks for pushing me to get them out there quickly.