Abstract: A tube cleaning system and method including a nozzle holder operable to secure nozzles in a nozzle arrangement, the nozzle arrangement corresponding to an arrangement of tubes of a tube bundle, and a nozzle positioning system operable to move the nozzle holder and nozzles secured therein, to cause the nozzles to engage a set of tubes of the tubes of the tube bundle, the nozzles configured to direct cleaning fluid into the set of tubes.

Abstract: A system and method for determining over-voltage and under-voltage thresholds in a voltage regulator are disclosed herein. A voltage regulator includes an over-voltage detector and an under-voltage detector that determine whether the voltage regulator's regulated output voltage is above or below predetermined over-voltage and under-voltage thresholds respectively. The over-voltage detector connects to an output port that provides a signal indicating that the regulated voltage output is greater than the predetermined over-voltage threshold and not lower than the predetermined under-voltage threshold. The under-voltage detector connects to an output port that provides a signal indicating that the regulated voltage output is lower than the predetermined under-voltage threshold and not greater than the predetermined over-voltage threshold. The voltage regulator also includes an input port that provides a test signal for testing the voltage levels of the over-voltage threshold and the under-voltage threshold.