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June 1, 2012
about 3 years ago
The reason they read smallest to largest left to right is because the unit is an electric kilo-watt hours meter. Just like the one on your house or apartment if you pay for your own electricity. GE or Western Electric invented or at least built the first ones that used an AC synchronous motor that sensed current flow. The dials were originally set up left to right, least significant to most significant. There are millions of them in the US. There are also millions of meter readers trained to read left to right and to record the KWH in that fashion.
As a future engineer you do not want to design anything that replaces an established piece of technology and force the public to have to learn something the exact opposite of what they’ve been trained to do. It will cause so much trouble its not worth the aggravation. My mother used to read her own power meter to keep an eye on the bills she paid. She caught enough mistakes to make it worth her time.
In the old electro-mechanical meters, the first dial was driven by a gear fashioned on the shaft of the synchronous motor. That dial then drives the next dial with a 10 to 1 reduction gear and so forth. Actually its a very efficient design and I have never seen any KWH meter having to be replaced my entire life (I remember black and white mono sound tube TVs). As designs go, its excellent with incredible durability. Think of it being very similar to a pendulum (Grandfather) clock. Its singular flaw is that it’s expensive to make, hence the electronic replacements.
To be honest I’m do not know if the all-electronic KWH meters are up to the task or that they will survive 50 to 60 years service.
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