Through a careful hydraulic calculation,this article confirmed the diameter of the polyethylene-aluminum-polyethylene composite pipes which are fixed after the natural gas meter set in a concentrated gas meter box.

Handshaking serial communication protocol of centralized meter reading system;

The automatic remote centralized meter reading system based on PSTN was introduced, and its constitution was given.

Main problems faced by low voltage power-line carrier technology when it applied in remote centralized meter reading system was introduced.

The automatic meter reading(AMR) system carrys out auto-transmitting of some data of measure point on time,inquiring about some information,showing and calculating and storing a meter s data on real time,and browsing web page of alarm information for legal departments.

To resolve the issue about the automatic meter reading,author designed a high-precision collect meter reading system of carrier wave on power,using the power carrier wave communication technology and the flush type technology.