| 摘要 |
<p>The minotor circuit for diesel engine heater plugs, consists of two separate magnet coils (4, 5) or alternatively , a single, bifilar-wound coil. Each winding, whose winding, whose ampere-turns figure is such to produce unequal, opposing magnetic fields, is connected to one or other of groups of parallel-connected glow-plugs (2). The number of plugs in each group is not the same. Should one of the plugs in one of the groups fail, the magnetic fields become unbalanced and a reed-switch contact is made (6) to operate an indicator lamp (8). A second switch contact (10) and indicator lamp are operated by an additional magnet coil, (9) in series with the supply to the other coils and plugs, when all plugs are functioning normally. In the event of an equal resistance change in both groups occurring due to the failure of plugs, whereby the first indicator would not function, the second indicator (12) goes out to indicate this condition.</p> |
