The flame sensor is peace and tranquility. Due to what?

In any room, a person feels comfortable only if it is secured from any factors that could threaten his life. It's not for nothing that long ago they say "my house is my fortress". With the development of new technologies, security has become more accessible. One of the many links in the security chain is the flame sensor.

Application area

The flame sensor has basically two widely used applications. Firstly, it is used in fire detection and fire extinguishing systems for buildings and structures. The second area of application of this small-sized equipment is the automation of safety of heating boilers and other gas consuming units.

Application of flame sensors in fire systems

In fire systems, usually three types of instruments are used: thermal, smoke and flame sensors. Thermal and smoke, especially in large rooms, may lose their effectiveness due to the fact that smoke can scatter over a large area. And since the sensor has a different sensitivity threshold, it may not work. The same is true with the thermal type, especially in the production premises during the summer period, when the temperature rises naturally, and possibly either a false alarm or a reset to a higher trip temperature.

An alternative to these devices, and even better in addition to them, fire alarm systems need to be equipped with flame sensors. They have no dependence on convection (heat and smoke transfer). A flame sensor, whose operation principle is based on the detection of radiation, which emits an open flame, is most common in fire alarm systems. The radiation from the open fire goes up, so the fire sensors must be installed on the ceiling of the room in such a way that the fire is in its direct visibility.

What are the flame sensors?

• Infrared.

• Ultraviolet.

• Ultrasound.

Infrared flame sensors are triggered by radiant heat from open flames, in contrast to heat, which react to the heating of air.

In rooms where there are electric heaters or other devices (sources of infrared radiation) use ultraviolet sensors.

Ultrasonic devices, triggered by movement, are more related to security systems. But since they are triggered by the movement of air, and it can be caused by a fire, as a result of which there is a movement of different-temperature air masses, the use of ultrasonic types in fire alarm systems is fully justified.

Features of the installation

The flame sensors that are part of the fire detectors must be correctly and correctly installed, because this determines the speed of the fire alarm and the fire extinguishing speed.

• They should be installed on the ceiling of the room. If the ceilings are tensioned, or their construction does not allow the installation, then the devices are placed on the walls along the perimeter, the columns, if any, or a system of special tension cables is used, the distance from the ceiling must not exceed 30 cm.

• One electrical circuit can combine no more than 10 sensors. This requirement applies only to residential and administrative premises. For production, the number of sensors is limited to five.

• The number of sensors must strictly correspond to the area of the room, based on the passport data.

Installation of the fire alarm system should be carried out by an experienced and qualified specialist. The flame sensor owns the owner of the premises, if he is not a specialist, he can not repair it. This must be done by a knowledgeable person, since in the future this can save lives.

Application of a flame sensor in boilers

The use of flame sensors in boilers is due to considerations of safety and economy. Since when the flame is unstable, the alarm is triggered, the boiler is set to work at a preset and economical operation. If the burner is suddenly extinguished, the gas signal or other type of fuel immediately stops at the signal of the device, which prevents the explosion hazard. The flame sensor circuit is individual for different types of boilers, furnaces and other gas consuming units.

From the models of flame detection devices of Russian production, the following can be noted:

• "Parus-002UF" is used in both single-sided and multi-burner boilers, as well as furnaces with incandescent lining, working on gas or liquid fuels.

• "Parus-003CUF" is used for selective control of boilers with several burners working on gas or liquid fuels.

• DMS-100M is used for selective control of boilers with several burners, working only with liquid fuel.

• DMS-100M-PF is used to control the fogging in a boiler operating on coal or wood.

• SL-90 - this flame sensor is used in boilers with no more than two burners, and the lining temperature of the unit and convective beams should not exceed 500 ⁰ С. Fuel for boilers is gas, coal and liquid fuel.