MINIATURE FAULT INDICATOR

摘要

A rugged, miniature, waterproof and lightweight magnetic latching indicator (10) with an auxiliary switch (70). The indicator (10) includes a solenoid (21), an elongated plunger (30) mounted in me solenoid (21), the plunger (70) supporting a first permanent magnet (32) with the magnet (32) being surrounded by specially dimensioned non-magnetic spacers (42, 46). The plunger (70) and solenoid (21) are packaged in a non- magnetic housing (20) with a solenoid locator (34), a top cap (50) and a bottom cap (66) maintaining the indicator (10) in a compact waterproof package. An indicator button (60) is mounted to the plunger (30) and a reed switch biasing spring (74) and second permanent magnet (78) are located between the bottom cap (66) and the solenoid (21). The plunger (30) moves from a retracted latching position to an extended position. In the retracted position, the indicator button (60) is retracted and not readily visible and the second permanent magnet (78) maintains the reed switch in a closed position. In the extended position, the indicator button (60) is readily visible and the second permanent magnet (78) is spaced from the reed switch (70) causing the reed switch (70) and any external circuitry connected in series with the reed switch (70) to open.