Among the main functions of the control of an electric motor we have the mechanical protection that is classified into three categories: drip and splash proof, fully enclosed and explosion proof. The explosion-proof motor is engineered for service in ball bearings environments saturated with gases and dust, susceptible to the danger of rapid ignition, and can not cause the same, either by spark or high heating. Its enclosure resists explosions of explosive gases or explosive mixtures specified therein, and prevents a surrounding flammable atmosphere from being ignited.
In the drip and splash-proof motor, all rotating parts, or under tension, are sheltered against dripping water from all directions, not allowing the direct or indirect entry of droplets or particles of liquids or solid objects that are spilled or motor. The fully enclosed electric motor is so enclosed that there is no exchange of the refrigerant medium between the exterior and the interior of the enclosure, and is not essentially sealed. Depending on the required characteristics, such motors may or may not have fan for their cooling.