A lot of watthour meters appear on ebay. Most are removed from service, but occasionaly a "surplus" new one shows up.
NO, in almost every juristiction, you are NOT allowed to put your own meter on your house...the meter belongs to the power company...it is their cash-register! Those few locales which allow consumer owned meters specify the meter must be independently certified for accuracy, and must be installed by a licensed meter service company. You cannot count on a used meter being accurate unless it has been tested against a standard of known accuracy.
Meters can be useful for load-study, like a manufacturer putting meters on seperate feeders supplying power to seperate processes in a plant.
Often, old residential meters end up being turned into lamps. Modification must be done on the meter to make it spin fast enough to catch your eye, as a 60W bulb in a lamp will barely make the disk turn.
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