Two and three wire utility data communications system
US5155481A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 25, 1990 |
| Grant date | Oct 13, 1992 |
| Priority date | — |
| Expiry date | May 25, 2010 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY04S20/30
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
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 …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.