Abstract: A mode selector apparatus according to the invention includes a variable output device, a control circuit responsive to the output device, and a user perceivable indicator responsive to the control circuit. The control circuit reads the output from the output device to determine if the output indicates a valid mode. If the output of the output device indicates a valid mode, the control circuit controls the user-perceivable indicator to indicate to a user that the mode selector is operating in a valid mode, and generates a valid mode indicating signal at a valid mode indicating output of the apparatus.

Abstract: In the present invention, several timer functions (e.g. delay on make, delay on break, recycle, single shot, etc.) are expressed in terms of a series of timer subfunctions, and code segments are developed for each identified subfunction. A program of a timer is established to include a plurality of subfunction code segments and a subfunction ordering table for determining the ordering of execution for the subfunction code segments. The ordering of subfunctions of the subfunction ordering table may be selectable in accordance with a model number input received at a program builder system adapted for use in programming the programmable timer. In one embodiment, the programming method provides for reprogramming of a timer including a control circuit having a one-time programmable processor.

Abstract: A safety circuit according to the invention controls operation of an equipment load. A manual control switch of the safety circuit is connected in series with the equipment load for controlling the flow of electrical current to the equipment load. The equipment load and control switch series combination are further in communication with a relay contact switch of the safety circuit, which, like the manual control switch controls the flow of electrical current to the equipment load. Arranged in this configuration the equipment load operates only if both the mechanical switch and relay contact are closed. If either the manual control switch or the relay contact are open, the equipment load does not operate.

Abstract: In the present invention, several timer functions (e.g. delay on make, delay on break, recycle, single shot, etc.) are expressed in terms of a series of timer subfunctions, and code segments are developed for each identified subfunction. A program of a timer is established to include a plurality of subfunction code segments and a subfunction ordering table for determining the ordering of execution for the subfunction code segments. The ordering of subfunctions of the subfunction ordering table may be selectable in accordance with a model number input received at a program builder system adapted for use in programming the programmable timer. In one embodiment, the programming method provides for reprogramming of a timer including a control circuit having a one-time programmable processor.

Abstract: The present invention is a timer module system including a timer module, program builder system for developing programs for loading into the timer module, and a model number data page for use in selecting the appropriate program for loading into the timer module. The timer module includes circuit elements configured for control by a timer processor system so that various timer functions, time delay functions, and time delay settings are realized by appropriate programming of the timer processor system. The program builder system includes a builder processor system having a program for developing a timer operating program in response to a user-input model number command selected using the model number data page. A breakable communication link is provided between the timer module and the program builder system to facilitate the transmission of developed timer operating programs from the program builder system to the timer module.

Abstract: The invention is an improved timer circuit for operating a heating or air conditioning unit which utilizes a single time delay generating circuit for delaying operation of both a compressor and a unit fan under certain operating conditions. A logic circuit for operating a fan relay is made responsive to the thermostat output and a time delay generating circuit output so that the fan relay is de-energized only in the case that the compressor has been turned off for at least the duration of a time delay generator timing period, and is in a state commensurate with a satisfactory building temperature. When the timer circuit is used in large-scale heating or air conditioning systems, the timing period of each timing circuit can be adjusted to a different duration so that a voltage lag problem on start up is avoided.

Abstract: A solid-state control circuit for selectively operating a deep fat fryer in a normal cook mode, a lower temperature hold mode, a fat melt mode and a safety thermostat test mode. During operation in the cook mode, a reference bias voltage is coupled to one input of a voltage comparator, and an operating bias voltage dependent on the temperature control setting and the actual cooking fat temperature sensed by a NTC resistive sensor is coupled to a second input of the comparator such that the comparator is effective to enable heating elements in the cooking fat when the fat temperature drops below the preset level. After a predetermined time interval during which the fryer is not being used, a timing circuit acts to vary the reference bias voltage and the operating bias voltage supplied to the comparator and thereby reduce the temperature of the fat to the lower preset hold mode temperature.