GAS METER

摘要

PROBLEM TO BE SOLVED: To provide a gas meter capable of reducing current consumption by preventing optical communication processing from being erroneously started according as an external light is made incident. SOLUTION: This gas meter is provided with an optical communication light receiving circuit 16 for receiving an optical communication start signal constituted of continuous ON signals added to the front of a mark signal before receiving the mark signal and a telegraphic message from optical communication equipment 2 and a start signal detecting part 18 for monitoring the light receiving state of the optical communication light receiving circuit 16 in a cycle longer than a sampling cycle at the time of detecting the mark signal, and for judging that the optical communication start signal is present at the time of detecting the state of the presence of light reception the prescribed number of times, and for starting optical communication processing.