Clyde N. Eugene OR. Got a complex one here. Large industrial client on Eugene Water & Electric 12.47kV primary metering with both CT and VT ratios. Bills seemed high for months but we finally figured out they have the VT ratio wrong in their billing system. CTs are correct at 1200:1 but VTs should be 14400:120 (120:1) and they're billing at 69:1. Anyone dealt with primary metered VT errors before?
VT Ratio Error on Primary Metered Account
Vince S. Hartford CT. Yes, Eversource had a similar issue on one of our primary metered accounts. The problem with VT errors is they affect both energy and demand calculations. The math gets complicated fast when you have both CT and VT multipliers wrong. Did you verify the actual VT nameplate ratios? Sometimes they install non-standard ratios.
Vince, checked the VT nameplates and they're definitely 14400:120 which should be 120:1 ratio. EWEB is billing at 69:1 for some reason. Client is on Schedule 40 Large Industrial and the overbilling is substantial - probably $8,000-$10,000 per month. The utility is being very difficult about admitting the VT programming error.
Randy Dawson here. Clyde, VT ratio errors on primary metered accounts can be tricky because they often stem from system voltage changes that weren't updated in the billing system. The 69:1 ratio suggests they might be using an old system voltage (8.28kV line-to-neutral) instead of the current 12.47kV system. You'll need to document the actual system voltage and VT installation. Request a formal meter test and make sure they verify both the CT and VT ratios simultaneously.
Pete M. Boise ID. Idaho Power had a similar voltage issue on one of our accounts. They had upgraded the distribution voltage years ago but never updated the VT multiplier in billing. Took a formal complaint to the Idaho PUC to get it resolved. The key was proving the actual system voltage versus what they were using for billing calculations.
Update from last month - EWEB finally sent their metering engineer out and confirmed the VT ratio error. System voltage is indeed 12.47kV but they were billing based on old 8.3kV ratios. They're correcting the billing back 24 months per their tariff. Refund should be around $180,000. Persistence pays off on these complex metering errors.