Patent ID: 8379362

Claim:
Indicating apparatus ( 1 ) for indicating the operating state of an electrical component of a load protection system, comprising: (a) a housing ( 3 ) containing a longitudinal chamber (C), said housing having a closed first end portion ( 4 a ) formed of a transparent material, and a second end portion ( 4 b ); (b) an indicating member ( 5 ) mounted for longitudinal displacement in said chamber between a retracted position spaced from said housing first end portion, and an indicating position contained within said first end portion; (c) resilient means ( 7 ) for normally biasing said indicating member relative to said housing toward said indicating position; (d) catch means ( 8 ) arranged in said housing chamber for retaining said indicating member in said retracted position, said catch means including: (1) a catch member ( 8 c ) arranged in said housing chamber for transverse displacement between a normal locked position and an unlocked position; (2) said catch member being formed of a ferromagnetic material and having a catch projection ( 8 a ) arranged to extend into a catch opening ( 8 b ) contained in said indicating member when said indicating member is in said retracted position and said catch member is in said locked position; and (e) solenoid means ( 9 ) responsive to a trouble voltage pulse (V T ) for operating said catch means from said locked position to said unlocked position, thereby to release said indicating member for displacement by said resilient means from said retracted position toward said indicating position.