What does the measurement range 0-100% LEL of a combustible gas detector mean?
"LEL" means Lower Explosion Limit. Combustible gases in the air in the event of an open flame explosion * low concentration, known as the lower limit of explosion - referred to as % LEL. English: Lower Explosion Limited.
Combustible gases in the air in the event of an open flame explosion * high concentration, known as the upper limit of the explosion - referred to as % UEL. English: UpperExplosion Limited.
Then what is the lower explosion limit?
Combustible gas concentration is too low or too high it is not dangerous, it is only mixed with air to form a mixture or more precisely meet the oxygen to form a certain proportion of the mixture will burn or explode. Combustion is accompanied by intense oxidation reaction with light and heat, it must have three elements: a, combustible material (gas); b, combustion aid (oxygen); c, ignition source (temperature). Combustion of gas can be divided into two categories, one is diffusion combustion, that is, volatile or from the equipment spray, leakage of gas, meet the ignition source mixed combustion. Another type of combustion, is a mixture of gas and air ignition combustion, this combustion reaction is intense and fast, generally produces great pressure and sound, also known as explosion. There is no strict distinction between combustion and explosion.
The relevant authorities and experts have been found on the combustion and explosion analysis of combustible gases, the development of combustible gas explosion limit, which is divided into the upper explosive limit (English upper explodelimit abbreviation UEL) and the lower explosive limit (English lower explodelimit abbreviation LEL?). Lower than the lower explosive limit, the gas content in the mixture is not enough to cause combustion or explosion, higher than the upper limit of the mixture of oxygen content is not enough to cause combustion or explosion. In addition, the combustion and explosion of combustible gas is also related to the gas pressure, temperature, ignition energy and other factors. Explosive limit is generally expressed in volume per cent concentration.
Explosive limit is the lower limit of the explosion, the upper limit of the explosion of the general term, combustible gases in the air only in the concentration of the lower limit of the explosion, the upper limit of the explosion will occur between the explosion. Below the lower explosive limit or above the upper explosive limit will not explode. Therefore, when conducting explosion measurement, the alarm concentration is generally set below 25% LEL of the lower explosion limit.
