초록 ▼

A circuit protection device connected between two lines of an AC power source self checks for an introduced simulated ground fault every half cycle during a period when a trip SCR cannot conduct. If the self check fails, the device is tripped on the next half cycle of different phase. Possible respo

A circuit protection device connected between two lines of an AC power source self checks for an introduced simulated ground fault every half cycle during a period when a trip SCR cannot conduct. If the self check fails, the device is tripped on the next half cycle of different phase. Possible responses to the self check failure include lighting an indicator lamp and locking out the device reset mechanism.

대표청구항 ▼

A circuit protection device connected between two lines of an AC power source self checks for an introduced simulated ground fault every half cycle during a period when a trip SCR cannot conduct. If the self check fails, the device is tripped on the next half cycle of different phase. Possible respo

A circuit protection device connected between two lines of an AC power source self checks for an introduced simulated ground fault every half cycle during a period when a trip SCR cannot conduct. If the self check fails, the device is tripped on the next half cycle of different phase. Possible responses to the self check failure include lighting an indicator lamp and locking out the device reset mechanism. further comprising a sustaining circuit which supplies the input power to the PWM driver from the second DC power. 42. The apparatus of claim 40, wherein the switch is a manual switch which is turned on when pressed by a user. 43. The apparatus of claim 40, wherein the switch is turned on when a user contacts the switch and turned off when the user does not contact the switch. 44. The apparatus of claim 43, wherein the SMPS continues to supply the second power regardless of on and off states of the switch after the switch is turned on and off. 45. The apparatus