Method and apparatus using phases for communication in thermostat circuit
US6307464A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 1, 2000 |
| Grant date | Oct 23, 2001 |
| Priority date | — |
| Expiry date | May 1, 2020 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF24F11/526
- WIPO fieldThermal processes and apparatus
- WIPO sectorMechanical engineering
Abstract
In a receiver circuit module (22) having a microcontroller (U1), an output line (FILTER_LED) connectable to a source circuit module (20) is also used as an input. A switch (SW2) disposed in the source circuit module is closed to change the wave form which is read by the microcontroller as an input signal to drive a 5V signal to the gate of a solid state switch (Q1) turning it on to thereby energize an output device in the source circuit module via the same output line (FILTER_LED). By means of the dual function of the output line the control can notify a user of an HVAC system, for example, of system problems with a blinking light and/or an audible alarm as well as serving to notify the user at a remote location that selected maintenance is due, such as a need to change filters without additional control lines. The source circuit module can be mounted near the thermostat of the HVAC system or on the central heating and cooling unit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.