Fire detection system including an automatic polarity sensing power and signal interface
US6738238B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 19, 2002 |
| Grant date | May 18, 2004 |
| Priority date | — |
| Expiry date | Jul 19, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG05B2219/23313
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A fire detection system comprising a control panel comprised of one or more controllers for controlling a plurality of devices. A pair of lines are operably connected to the control panel and the devices for communicating signals between said control panel and said devices. A circuit for providing a polarity sensing power and signal interface is provided between the control panel and devices to reduce to reduce system maintenance. The circuit includes a rectifier circuit operably connected the pair of lines wherein the rectifier circuit is comprised of at least two transistors for providing the circuit with a low-impedance path to ground and providing the circuit with a polarity insensitive output. Capacitors may be operably connected to the transistors in the rectifier circuit to keep the transistors turned on when a low voltage is applied to the rectifier circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.