If the engine has a heating resistance, it is important that it is energized whenever the engine is not running. This process is also used at times when the electric motor is installed, but without being used for a long period of time.
In such cases, it varies according to the ambient conditions, it can happen to the condensation of water inside the motor, consequently causing the fall in the insulation resistance.
It is worth remembering that the heating elements must not be energized at the moment the motor is running. In the case of machines which are not installed properly at the time of their acquisition, it is advisable to store them in dry places with a relative humidity of not more than 60% at an ambient temperature above 5 ° C and below 40 ° C, without any contact with dust, vibrations of any kind, gases and corrosive agents. It is also necessary that the engine has a temperature considered to be invariable, be kept in the normal position and no objects are supported on them.