| 摘要 |
<p>The preheating circuit connects the ignition plugs (1) briefly to the power supply via one series resistor (5) at the start of a first heating period. This resistor is then switched out so that the first heating period continues without it. A second heating period is initiated by switching the resistor back in and keeping it in for the duration of the second period. Alternatively, the resistor used for the initial part of the first period of heating may be a temp. sensitive resistor (9) whose resistance drops from a high initial to a low final value whilst the resistor used in the second heating period may be a normal resistor. The temp. sensitive resistor can therefore be kept in the circuit all the time.</p> |
