Smoke Sensor


Ionization Smoke Detector Operation
A typical ionization tube consists of two electrically charged plates and a radioactive source (typically Americium 241) for ionizing the air between the plates. The radioactive source emits particles that hit the air molecules and dislodge their electrons. Because the molecules lose electrons, they become charged ions. As other molecules gain electrons, they become charged ions. Equal numbers of positive and negative ions are created. The charged ions are attracted to the charged electrical plate, while the negatively charged ions are interested in the charged plate. This creates a little ionization current which will be measured by electronic circuitry connected to the plates (“normal” condition within the detector). Particles of combustion are much larger than the ionized air molecules. As particles of combustion enter an ionization tube, ionized air molecules collide and mix with them. Some particles become charged and a few become charged. As these relatively large particles still combine with many other ions, they become recombination centers, and therefore the total number of ionized particles within the chamber is reduced.

Smoke Detectors 101 - differing types of Detectors
Most homeowners do not know that smoke detectors are available two types: ionization smoke detectors and photoelectric smoke detectors. At now you would possibly wonder why anyone even bothers with knowing the difference.
While it's going to not bring the foremost riveting article to read, knowing how ionization and photoelectric detectors work differently can potentially save your life at some point.

Ionization Smoke Detectors
Each ionization smoke detector holds a small amount of material, which is placed between two electrically charged plates. This successively creates a current between the 2 plates. When smoke gets into the detector, the present is disrupted and therefore the alarm is triggered. Ionization smoke detectors are known to figure better with flaming fires—these are fires with aggressive, open flames. Their effectiveness with other sorts of fires, like smoldering fires, isn't as great. That’s why we've another sort of smoke detector.

Photoelectric Smoke Detectors
The second hottest sort of smoke detectors is photoelectric detectors. Unlike ionization detectors, these detectors use a light-weight -weight source and a light sensor to detect smoke. Once the smoke enters the detection chamber, the smoke particles block the sunshine beam and partially reflect light onto the sensors. This successively trips the alarm. Since many smoldering fires fill the space with dangerous fumes and smoke way before getting to the open-flame stage, these sorts of detectors tend to be better at early detection.

Battery-Powered Detectors
Most detectors out there are powered by batteries. Since smoke detectors generally don't use tons of power, many of those battery-powered models require little or no maintenance on a yearly basis. However, every battery features a limit and you do not want to seek out yourself during a fire with a dead smoke detector. There’s nothing inherently wrong with battery-powered smoke detectors, but you've got to be absolutely vigilant about replacing spent batteries.

Smoke Sensor
Smoke Sensor