Circuit for automatically sequencing a valve mechanism

摘要

A solid state circuit for sequencing a valve mechanism from its normal operating position through a sequence of cycles to blow down various different lines of the network to which the valve mechanism is connected. The circuit may be set to initiate its sequence at one of a number of time periods such as once a day or once a week. Once initiated, the circuit operates a motor drive for the valve mechanism continuing for a timed interval followed by a delay or dwell at each blow down position. A signal is provided to indicate that the circuit is about to enter a blow down sequence followed by the sequence itself. Various alarms and safeguards are provided for the sequence.