| 摘要 |
A control arrangement for a direct ignition type fuel ignition system including a timing circuit having a timing capacitor which charges in response to application of power to the system defining a trial for ignition interval during which a controlled switching device is enabled to operate a flame relay to energize a fuel valve to supply fuel to a burner for ignition by sparks provided by a spark generator, the controlled switching device being disabled, deenergizing the flame relay when the timing capacitor becomes fully charged before the fuel is ignited, and the controlled switching device being maintained enabled through the action of a flame sensing circuit which is coupled to the timing circuit only when a flame is established. The control arrangement includes a reset circuit having a discharge network which enables rapid discharge of the timing capacitor whenever the system is deactivated, the discharge network being normally decoupled from the timing capacitor, and being coupled to the timing capacitor when power is disconnected from the reset circuit. In one embodiment, the fuel valve is energized over a path provided by contacts of the flame relay and contacts of a checking relay, which is energized over normally closed contacts of the flame relay at the start of each operating cycle, the checking relay also enabling the timing circuit and the spark generator.
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