摘要 |
In a triac power switching system, two triacs are connected in series between an AC power source and a load. Each time power is applied to a load, the triacs are tested by first turning on one of the triacs while maintaining the other triac turned off, then turning on both triacs to apply power to the load for a set time interval and then turning off one of the triacs and determining whether power is still applied to the load. If power is applied to the load while either one of the triacs is supposed to be off, an alarm is sounded. In addition, if power is not applied to the load when both triacs are turned on, an alarm is sounded.
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