Flame monitor, for a fossil fuel burner, has a semiconductor element with a light-sensitive surface and an evaluation circuit for the electrical resistance according to exposure to light and is free of cadmium sulfide

摘要

The flame monitor (1), for a burner using fossil fuel e.g. oil or gas, has a light-sensitive circuit with an electrical resistance dependent on light in the visible spectrum falling on it for evaluation (13). The light-sensitive circuit is a GaP or S semiconductor element (17), with a light sensitive maximum of 450-600 nm. The light from the flame falls on its surface through a transparent head. The semiconductor element has two transistors (19,20) with a resistance (21) between them in a Darlington circuit (18), together forming a semiconductor component.