08511577 is referenced by 32 patents and cites 181 patents.

A thermostat includes a plurality of HVAC (heating, ventilation, and air conditioning) wire connectors including a connection to at least one call relay wire. The thermostat may also include a powering circuit, including a rechargeable battery, which is configured to provide electrical power to the thermostat by power stealing from a selected call relay wire. The power stealing may include an active power stealing mode, in which power is taken from the same selected call relay wire that is used to call for an HVAC function, and an inactive power stealing mode in which, in which no active call is being made. The powering circuit may be configured to substantially suspend (or at least reduce the level of) power stealing for at least a first time period following each transition of the thermostat from between operating states.

Title
Thermostat with power stealing delay interval at transitions between power stealing states
Application Number
13/601574
Publication Number
8511577 (B2)
Application Date
August 31, 2012
Publication Date
August 20, 2013
Inventor
Ian C Smith
Palo Alto
CA, US
Edwin H Satterthwaite Jr
Palo Alto
CA, US
Daniel Adam Warren
San Francisco
CA, US
Agent
Kilpatrick Townsend & Stockton
Assignee
Nest Labs
CA, US
IPC
G05D 23/00
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