초록 ▼

An under frequency protection thermostat-type device includes a thermostat-type housing, a transformer, a line under frequency (LUF) detection and measurement module, a microcontroller, and a load switch. The transformer is adapted to be electrically connected to a primary voltage source having a pr

An under frequency protection thermostat-type device includes a thermostat-type housing, a transformer, a line under frequency (LUF) detection and measurement module, a microcontroller, and a load switch. The transformer is adapted to be electrically connected to a primary voltage source having a predefined frequency level and disposed within the housing. The LUF detection and measurement module is electrically connected to the transformer and adapted to detect a line under frequency condition from a signal received from the transformer. The microcontroller is connected to the LUF detection and measurement module and is adapted to send a command to disengage and engage an electrical load as a function of a measured frequency of the voltage source over a predefined period of time. The measured frequency is compared to a predefined frequency threshold. The load switch is connected to the microcontroller and is adapted to respond to a command from the microcontroller to disengage and engage an electrical load from the voltage source.

대표청구항 ▼

What is claimed is: 1. An under frequency protection thermostat-type device comprising: a thermostat-type housing; a transformer adapted to be electrically connected to a primary voltage source having a predefined frequency level and disposed within said housing; a line under frequency (LUF) detect

What is claimed is: 1. An under frequency protection thermostat-type device comprising: a thermostat-type housing; a transformer adapted to be electrically connected to a primary voltage source having a predefined frequency level and disposed within said housing; a line under frequency (LUF) detection and measurement module electrically connected to the transformer and adapted to detect a line under frequency condition from a signal received from the transformer; a microcontroller connected to the LUF detection and measurement module and adapted to send a command to disengage and engage an electrical load as a function of a measured frequency of the voltage source over a predefined period of time, wherein the measured frequency is compared to a predefined frequency threshold; and a load switch connected to the microcontroller adapted to respond to a command from the microcontroller to disengage and engage an electrical load from the voltage source. 2. An under frequency protection thermostat-type device comprising: a thermostat-type housing; a transformer disposed within said housing; a line under frequency (LUF) detection and measurement module electrically connected to the transformer and adapted to detect a line under frequency condition from a signal received from the transformer; a microcontroller connected to the LUF detection and measurement module and adapted to send a command to disengage and engage an electrical load as a function of a measured frequency of the voltage source over a predefined period of time, wherein the measured frequency is compared to a predefined frequency threshold. 3. The device according to claim 2, wherein the transformer is adapted to be electrically connected to a primary voltage source having a predefined frequency level. 4. The device according to claim 2, further comprising a load connected to the microcontroller and adapted to respond to a command from the microcontroller to disengage and engage an electrical load from the voltage source. 5. The device of claim 2, wherein the LUF detection module is adapted to determine the line frequency status of each power line cycle by counting ticks on an interval timer between two successive zero-crossing falling edges of the power line, thereby generating the measured frequency of the voltage source. 6. The device of claim 2, wherein the microcontroller sends a command to disengage the load when the measured frequency over the predefined period of time is below the frequency threshold and sends a command to engage the load when the measured frequency is above the frequency threshold.