Search results
Results From The WOW.Com Content Network
The key components are an infrared source, a light tube, an interference (wavelength) filter, and an infrared detector. The gas is pumped or diffuses into the light tube, and the electronics measure the absorption of the characteristic wavelength of light. NDIR sensors are most often used for measuring carbon dioxide. [2]
System tests could be conducted in one of two ways: In a coded pull station, there is either a test hole on the front (usually activated with an Allen wrench) or a test switch on the inside. Turning the switch one way causes the notification appliances to sound continuous (or in the case of single-stroke bells, ding once). Turning it the other ...
The EN 54 series of standards covers the following topics and product groups related to fire detection and fire alarm systems: [6] [7] Introduction: the introduction to the series of standards contains a diagram of a fire alarm system as well as numerous definitions of terms that are used in the other parts of the series of standards.
The standard details requirements for a range of alarm systems including central station burglar alarms, police station connected alarms, local alarms, proprietary systems, holdup alarms, and digital alarm communicator system units. It also covers power supplies essential for burglar-alarm equipment operation.
The gas sensors in CO alarms have a limited life span, typically two to five years. [7] Newer models are designed to signal a need to be replaced after a set period. CO detectors all have "test" buttons like smoke detectors, but the test buttons only test the battery, electronic circuit, and buzzer, not the alarm’s ability to sense gas.
A gas detector can sound an alarm to operators in the area where the leak is occurring, giving them the opportunity to leave. This type of device is important because there are many gases that can be harmful to organic life, such as humans or animals. Gas detectors can be used to detect combustible, flammable and toxic gases, and oxygen depletion.
Get AOL Mail for FREE! Manage your email like never before with travel, photo & document views. Personalize your inbox with themes & tabs. You've Got Mail!
Battery 15 battery+ through ignition switch 16, 54/15 30 from battery+ direct 30/51 30a from 2nd battery and 12/24 V relay: 31 return to battery- or direct to ground 31a return to battery- 12/24 V relay 31b return to battery- or ground through switch 85d 31c return to battery- 12/24 V relay 31, 31a Electric motors; 32 return 31 33