| 摘要 |
<p>A condition control system which utilizes digital logic to respond to the state of the condition being sensed. The control system utilizes a condition responsive element that is energized from an alternating current source and controls a first alternating current type of amplifier. The output of the amplifier is compared with a periodically generated pulse or logic command in an S-R latch circuit which is made up of a pair of NAND gates in a cross-connected configuration. The digital logic is arranged so that an output transistor and relay are energized only when the system senses the presence of the desired condition thereby indicating that it is safe to energize associated equipment.</p> |
