| 摘要 |
FIELD: domestic electrical appliances. SUBSTANCE: with device connected to rated supply mains, its triac 2 passes current since positive potential is applied to gate electrode 9 through resistor 10 with the result that voltage is applied to load 1. In case of voltage threshold exceeding specified value, threshold element 8 starts conducting, and then electronic switch 7 does so causing application of negative potential to triac gate electrode 9. Triac 2 is cut off and load 1 is deenergized. As soon as supply voltage is brought to rated value, threshold element 8 stops passing current, then electronic switch turns off, and positive potential is applied to gate electrode 9. Load is thrown on line again. EFFECT: improved reliability and efficiency of protection of all domestic appliances irrespective of their operating conditions and provision for their automatic turn-on at rated voltage. |
