What is an Explosion Proof Motor?
Explosion-proof motor is a type of motor with explosion-proof performance. It is a kind of motor that can be used in flammable and explosive places, and it does not produce electric sparks during operation. It has a structure different from that used in ordinary environments. It can prevent the combustible gas and dust outside the motor from entering the motor to the greatest extent, or even if it enters, explosion-proof motor will not ignite the combustible gas and dust in the surrounding environment from the flame out of the casing when short-circuited and caught in the interior.
Why use explosion proof motor?
A motor can create an explosion by one of two means:
1. The surface of the motor will become so hot during operation that it will ignite steam, gas or dust.
2. A single arc caused by a motor failure (such as winding insulation failure or power supply problem) will ignite surrounding materials.
When operating in hazardous locations, the use of explosion-proof motors is essential for safety. Explosion-proof motors are designed for use in hazardous environments where flammable gases, dust or fibers are present. The motor generates heat under normal operating conditions. If the motor coil fails, sparks may occur. In environments where certain hazardous materials are present, excessive motor housing temperature or sparks that are not properly controlled may cause an explosion or ignite a fire. Explosion-proof does not mean that the motor will never explode, nor does it mean that it will not be affected by external explosions. On the contrary, the explosion-proof motor has the function of preventing the explosion of the internal motor from igniting a larger flammable atmosphere in the environment. Explosion-proof motors are mainly used in coal mines, petroleum and natural gas, petrochemical, chemical and other industries. In addition, it is also widely used in textile, metallurgy, urban gas, transportation, grain and oil processing, papermaking, medicine and other sectors. As the main power equipment, explosion-proof motors are usually used to drive pumps, fans, compressors and other transmission machinery.
What environments do an explosion proof motor help in?
Motor in a Class I environment (UL designation), where flammable gases, vapors or liquids are present, are designed to prevent an internal spark or flame from escaping the motor into the hazardous environment. They are also designed so the motor case temperature does not exceed safe temperatures for environments where gases, vapors or liquids are present.
Motor in a Class II or Class III environment (UL designation), where certain dust or fibers are present, are designed so the motor case temperature does not exceed safe temperatures for combustible dust and fiber environments. While simply operating the motor at a lower current rating reduces the heat it produces, other failsafe methods to limit an excessive motor case temperature condition include thermostats that disengage the motor power before it reaches critical temperatures.