Apparatus and method for an inbound telemetry device to sense telephone line status
US6487282B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 31, 2000 |
| Grant date | Nov 26, 2002 |
| Priority date | — |
| Expiry date | Jul 31, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M11/002
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A telephone-based automatic meter reading (AMR) system includes a telemetry device through which a host computer can collect meter readings remotely. So that the telemetry device does not interfere with customer usage of other telephone devices on the telephone line, an apparatus and method is provided which enables the telemetry device to sense both the static off-hook status and the dynamic off-hook status of the telephone line. Numerous circuit components in the telemetry device are shared in sensing both the static and the dynamic off-hook status. Whenever it is determined that a telephone device is, or has become, off-hook, the telemetry device is prevented from using the telephone line. Isolation between the telephone line and the meters is ensured using a transformer and optocouplers.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.