| 摘要 |
620,887. Indicating faults. WIJK, H. VAN DER. Jan. 29, 1947, No. 2734. Convention date, Oct. 3, 1942. [Class 37] A fault indicator for a single conductor system, particularly for ships, comprises two lamps in series between the main conductor and earth and an auxiliary conductor adjacent to the main conductor connected to the junction of the lamps. In the system shown generators 1 have one pole earthed and the other connected to a bus-bar 5, from which are fed distribution boxes 10, 11 and a motor 13. Sub-distribution boxes 14, 15, 16 are supplied from the box 10 and a motor 17 is supplied from the box 11. An auxiliary conductor 18 is embedded in the insulation of the cables and may consist of a conductor wrapped spirally, with short pitch, around the insulated core or of a braided wrapping or an enveloping strip. The thickness of insulation is made sufficient for the whole voltage between the core and the auxiliary conductor as well as between the auxiliary conductor and earth. At each control point a pair of lamps 19, 20, each adapted for the normal voltage of the system, are connected in series between the conductor and earth, the auxiliary conductor 18 being connected to their junction. If a fault X occurs between the auxiliary conductor 18 and earth, the lamp 20 is short-circuited and the lamp 19 glows brightly. If a fault Y occurs between the main and auxiliary conductors, the lamp 19 is short-circuited and the lamp 20 glows at full voltage. |
