Solid-state Electronic Apparatus to Provide Reliable Electric Power for Smart Communicating Thermostats

摘要

A solid-state adapter provides a common-wire functionality to an HVAC system including four wire connections between a thermostat and HVAC equipment The adapter may include an embodiment of an efficient fan controller to provide a fan-off delay based on the duration of a heating cycle or the duration of a cooling cycle where the duration includes at least one duration selected from the group consisting of: a heating on time, a heating off time, a cooling on time, and a cooling off time. The solid-state common-wire adapter uses a TRIAC, capacitor and load resistor to provide a small, low-cost and reliable electronic device which repurposes the existing wiring harness to add a common wire functionality where previously one did not exist. The common-wire function is required in many buildings with pre-existing low-voltage 4-wire electrical harnesses in order to provide continuous and reliable power to Smart Communicating Thermostats that connect to the internet using a wireless Ethernet network officially referred to as the IEEE 802.11 standard.