Posted for Bjarney:
Electric utilities worldwide use GPS clocks for system frequency tracking, that are routinely accurate to 0.000 000 05 seconds. In the US, regional electric coordinating councils take frequency accuracy very seriously, for not doing so would make it very hard to conduct bulk-power transactions. {It takes electricity about 0.000 000 001 seconds to travel 1 foot through cable.}
Read over your meter’s manual and consider its published accuracy figures—it’s likely there is some measurement error.
- Bjarney
