摘要 |
Electrical consumption registered in a watthour meter is converted into an electrical analog suitable for transmission to a remote monitoring site by reflecting light off the watthour meter rotor, the light being periodically interrupted during each rotor rotation by a darkened light absorbing area of the rotor which traverses the light beam, passing the light to and from the meter through fiber optic cables and digitally counting at a distant location each of the pulses corresponding to the rotor rotation which are transduced from the light reflections. By generating the light from an AC signal, AC signal processing techniques employed in the light reflection detection circuitry ensure a useable electrical analog with minimal likelihood of error otherwise arising from spurious noise and varying ambient temperature related signals.
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