Abstract: Heating, Ventilating, and Air Conditioning (HVAC) and refrigeration systems have a thermostat to allow users to set a desired temperature for living and storage spaces. The output from the thermostat is a so-called “Call for Cool” signal (CfC) used to start the system compressor and begin the cooling process. A circuit which interrupts the CfC signal from a thermostat to the compressor without using specific input and output connections to define the CfC signal is disclosed. The circuitry monitors the temperature of the evaporator, and if the temperature dips too low, the compressor is disengaged until the measured temperature rises above a safe level.

Abstract: An electronic system for controlling the operation of a hand-held pull strap closure unit. The system includes a central processing unit which controls peripheral circuitry for directing commands to a motor within the hand-held unit. The system further includes a circuit for monitoring motor torque and a hand-held unit identification circuit for identifying each unit with an individualized code. The CPU may be accessed via an external communications port to store user-selected operational parameters in a memory circuit. These parameters may include time of day, calendar, and motor torque limits for each device.