MANUAL OVERRIDE SWITCH TO FULFILL UL REQUIREMENT FOR MANUAL AND AUTOMATED SWITCHING IN SMART ISLANDING SWITCH SYSTEMS

원문 (중국어)

An overlay manual override system is provided to make relay devices compliant with UL 1741. Said relay devices must have a manual switch that can be moved linearly between an ON position, an OFF position, and a NULL position. The system includes an overlay switch that receives the relay's manual switch, an overlay switch holder, an OFF position sensor, an ON position sensor, a cover, and a cover sensor that detects when the cover is open. The overlay switch holder gets fixedly coupled to the relay. The overlay switch can actuate the manual switch between the ON, OFF, and NULL positions. When the overlay switch is in either the ON position or the OFF position, or when the cover is open, the electrical control of the relay cannot override the state of the overlay switch and manual switch, thus making manual override and electrical control of the relay mutually exclusive.