Abstract: 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.

Abstract: A system and method for remotely monitoring load tap changes on utility-type equipment are disclosed. In one example embodiment, a sensor measures a voltage before a tap change and compares the measured voltage to a voltage after the tap change. From this information, the direction of the tap change and the distance traveled can be determined. The system and method can also include a timer to measure an elapsed time required to complete a particular tap change and use this time information to determine the distance traveled. The direction of the tap change can be determined from a sensor that triggers the timer. The system and method thereby enable efficient and cost-effective remote monitoring of load tap changes and positions.