The smoke alarm flashes only once. Once there is smoke, the ionization chamber outside will be closed quickly. If the normal motion of charged particles is disturbed, the current and voltage will change, which will destroy the balance between the inner and outer ionization chambers. So the wireless transmitter sends out a wireless alarm signal to inform the remote receiving host and send alarm information.

Generally, when the temperature sensor detects that the surrounding environment reaches the set alarm temperature, it will generate an alarm signal. In life, the smoke sensor will flash red.

Extended data:

Smoke alarm, also known as fire smoke alarm, smoke sensor, smoke sensor, etc. The power supply is supplied by the bus, which can be connected with multiple buses to form an alarm system and communicate with the fire alarm controller through networking. There is no sound at the scene when the alarm is given, and the host has an audible and visual prompt. This kind of smoke alarm device is generally called smoke detector. Smoke detectors are divided into areas with and without address codes.

References:

Baidu encyclopedia-smoke alarm