Automatic firing device for gas central heating boiler - has microprocessor control of igniter and gas supply control valve for burner

摘要

The automatic firing device is coupled via a network stage (1) to a heavy current supply network and has a microprocessor (2) acting as a programmable process control coupled to the DC output (4) of the network stage via a supply line (3). The gas burner has a glow igniter (5) coupled via a second supply line (6) to a heavy current output (7) of the network stage, the driver (8) for the igniter coupled to a control line (9) from the microprocessor. An inductive flame sensor supplies a flame indication signal back to the microprocessor. The gas supply for the burner is controlled via a magnetic valve (13) controlled via a valve driver (15) from the microprocessor, the latter incorporating a watch-dog function for closing the valve upon detection of a programme error. ADVANTAGE - Ensures reliable explosion protection.