I used to have to do meter testing on disputed accounts in the days of Norweb
Used 2 is fire or consumer's cooker to give a load. Measure volts and current, then time disc for 5 minutes and multiply by 12 to give one hour equivalent. Later we had an electronic unit with ct's which did a lot of it. Not very scientific or accurate! Can't remember the accepted accuracy. Dear mestic meters were certified as accurate for 15 years I think, and had to be changed if ESMA seals were in sding (ones on the main case).
Used 2 is fire or consumer's cooker to give a load. Measure volts and current, then time disc for 5 minutes and multiply by 12 to give one hour equivalent. Later we had an electronic unit with ct's which did a lot of it. Not very scientific or accurate! Can't remember the accepted accuracy. Dear mestic meters were certified as accurate for 15 years I think, and had to be changed if ESMA seals were in sding (ones on the main case).
