Reader/programmer for two and three wire utility data communications system
First Claim
1. A reader/programmer for communicating with a utility meter over at least two wire lines, comprising:
- means for generating an interrogate signal;
first means for demodulating a data signal received from the utility meter over the wire lines, the data signal consisting of a current in the wire lines which varies in accordance with data being transmitted from the utility meter when the reader/programmer is connected via two wire lines; and
second means for demodulating the data signal received from the utility meter over the wire lines, the data signal having characteristics which vary in accordance with data being transmitted from the utility meter when the reader/programmer is connected via at least three wire lines.
6 Assignments
0 Petitions
Accused Products
Abstract
A two wire/three wire utility data communications system for remotely reading utility meter registers. In the two wire version, a hand-held reading unit is inductively coupled over two wires via a port located remotely from a meter register. Alternatively, a meter interface unit (MIU) may be connected directly to the register via three wires. Each register includes one or more wheel position encoders. An AC interrogation signal is applied by the reading unit to encoder circuitry at the meter which powers the circuitry and causes the position of each encoder wheel to be read. In the two wire mode, register display information (e.g. the current meter reading) is transmitted back to the reading unit by varying the load (impedance) presented by the register side of the circuit. This causes a corresponding variation of the amount of current drawn from the reading unit. The current-modulated signal is decoded by the reading unit and converted into a register reading. The system can also operate in a three wire mode and read older fourteen wire encoded registers. Other features include remote programmability of register characteristics, the ability to interrogate multiple registers which share a common data bus, verification of encoder wheel positions before accepting a reading, real-time flow rate/leak detection, pulse output, and the capability of reading compound meters (i.e. meters having two registers to separately measure high/low flow rates).
-
Citations
27 Claims
-
1. A reader/programmer for communicating with a utility meter over at least two wire lines, comprising:
-
means for generating an interrogate signal; first means for demodulating a data signal received from the utility meter over the wire lines, the data signal consisting of a current in the wire lines which varies in accordance with data being transmitted from the utility meter when the reader/programmer is connected via two wire lines; and second means for demodulating the data signal received from the utility meter over the wire lines, the data signal having characteristics which vary in accordance with data being transmitted from the utility meter when the reader/programmer is connected via at least three wire lines. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27)
-
Specification