Fault recovery procedure for heat-reactivated dryer

摘要

A method of operating a microcomputer for controlling a heat- reactivated dual-chamber gas adsorber ensures safe and reliable operation of the adsorber by recovering from disruption of the microcomputer execution sequence and sensing failure of the power control components which enable regeneration of the adsorbent. A non-volatile memory stores a code designating the "active-task" or subdivision of the adsorber cycle being controlled by the microcomputer. A reset circuit includes a watchdog timer responsive to disruption of the microcomputer's execution sequence. Upon reset of the microcomputer, the hardware components are set to an initial state and checked before resuming execution of the interrupted task. A purge circulation blower, for example, is turned on in the event that the heater cannot be turned off. The regeneration task is treated as a special case, and the non-volatile memory preferably stores an indication of whether regeneration was completed before the end of a predetermined regeneration time interval as well as how long regeneration had taken place.