| 摘要 |
PURPOSE:To prevent a tube from being fused at the time of misfitting a preheating control system which conforms to specifications, by a method wherein a spare terminal of a timer for passing current to a glow plug is provided with a function of stopping the passing of current to the glow plug even if a voltage is impressed. CONSTITUTION:An input terminal T1 of the timer 12 detects the condition wherein an engine switch key is in the ON position, and an input terminal T2 detects the condition wherein the switch is in the start position. An output terminal T3 operates a glow relay for passing current to the glow plug. An input terminal T4 is used to input a cooling-water temperature from a water temperature sensor, and an output terminal T5 is used to pass current to a glow lamp for indicating a preheatig stand-by time. In the timer 12, the spare terminal T6 is connected by a wire 20 to a point between a resistance R and a capacitor C which are provided to determine the time constant of the timer 12. If the timer 12 is misfitted to a glow-plug preheating control system other than the one desired, a voltage is impressed on the spare terminal T6, so that the capacitor C is instantaneously charged, a preheating timer P1 does not operate, and no current is passed to the plug. |
