Abstract: A water softening apparatus is provided including a water tank, a brine tank, chlorination electrodes for providing chlorination to water flowing in the water tank and a circuit for providing electrical energy to the chlorination electrodes. A microprocessor controls the circuit, with the microprocessor being software controlled to determine when regeneration should commence, when backwash should terminate, when brine/slow rinse should commence, when the chlorination electrodes should be energized, when the chlorination electrode energization should terminate, when brine/slow rinse should terminate, when fast rinse should commence, and when fast rinse should terminate.

Abstract: A water softening system is provided in which a determination is made whether the slow rinse cycle of a regeneration has been completed or is abnormal. A reference cell and a spaced sensing cell are provided in a water tank. The impedance difference of the solution between the reference cell and the sensor cell is sensed. If the impedance difference is a first state, then after a predetermined period of time a determination is made if the impedance difference is a second state. If the impedance difference is a second state, then after a predetermined period of time a determination is made if the impedance difference is a third state. If the impedance difference is a third state, this indicates that the sodium ion concentration is uniformly reduced in the zone between the reference cell and the sensing cell and that the slow rinse cycle has been completed.

Abstract: A temperature controller utilizes a square wave signal whose pulse width is incrementally stepped in variable increments by a variable count in a register to determine the temperature being read by a sensor. The square wave signal is integrated to provide an analog signal that is compared to an analog signal provided by the sensor. When the amplitude of the integrated analog signal approaches the amplitude of the signal from the sensor, the count in the register is noted and the temperature is determined from the count by a piecewise linear equation. The temperature thus obtained is compared to a user selected temperature to control the temperature in the sensed area. The controller also includes a monitoring system that monitors the status of switching devices that are controlled by the controller to assure that the status of the switching devices corresponds to the status selected by the controller.