| 摘要 |
PURPOSE:To perform firing automatically even if power failure or voltage drop occurs during the time from preceding firing to current extinguishing, by providing the contact, which is operated only during the operation of the timer, in parallel with the self-holding contact of the operation holding relay. CONSTITUTION:Relay R1 is operated by the extinguishing switch which is not shown in the figure, and relay R1 is self-held by its contact r1. When the firing switch which is not shown in the figure is turned on at the refiring time, a current is flowed through power supply line 102 and contacts r1, r1.19 to start the firing sequence. If power failure or voltage drop occurs during extinguishing self-holding of relay R1 is released; however, if a prescribed condition is satisfied by switch 7 interlocked with the time and burner temperature detecting relay r5, that is, if firing should be performed, relay R1 is driven to start the firing sequence. |
