The utility model provides a gas detection device which mainly comprises a PWM (
Pulse Width Modulation) speed regulation module, a vacuum self-priming pump, a
gas chamber, a detection chamber comprising different gas sensors and
signal conditioning circuits, a main control board, a stepping motor driving module, a stepping motor, an incremental
encoder and the like which are fixed in a shell of the device, the parts can be physically and logically connected by adopting wires or communication protocols, the
gas chamber can be respectively communicated with different detection chambers, gas to be detected can enter the different detection chambers through the
gas chamber after the gas chamber is communicated, and the concentration of the gas is detected by utilizing different gas sensors and
signal conditioning circuits; and a detection result is uploaded to the
distributed control system, and alarm and real-time display are carried out through the sound-light alarm module and the display module. The real-time detection of different combustible and toxic gases is realized, the expansibility and universality of the gas detection device are greatly improved, the inventory occupation of power
plant spare parts is reduced, and the economic benefit is improved.