Megger.
An electrical test instrument that uses a high-voltage output for insulation testing and high-resistance measurements.
Motor Starter
A device used to supply full line voltage to a motor and include overcurrent protection.
Motor Nameplate
Every electric motor is labeled with a motor nameplate. The motor nameplate contains information about important motor parameters. NEMA (National Electrical Manufacturers Association) specifies the nameplate layout and data.
Metric Units
These are measurements units used in most of the world. Typical units are meters, centimeters, kg (kilogram), N (Newton’s), and seconds.
Magnetic Field.
Comprised of lines of force, this is the field in the region surrounding a magnet through which magnetic forces act. This field is most intense near the poles of the magnet and as the distance from the magnet is increased, the lines of force become weaker and weaker (because of the surrounding air’s high reluctance), until they are finally nonexistent.
Magnetic Flux.
The average field intensity of a magnet multiplied by its area.
Magnetic Lines of Force / Magnetic Flux Lines.
Imaginary lines that indicate the strength and direction of a given magnetic field.
Motor Action.
An action that occurs by the inductive reaction when two opposing electromagnetic fields push away from each other, motor action is the mechanical stress placed on the windings and iron core of a transformer when the secondary circuit or winding is short-circuited.
Mutual Induction / Mutual Inductance.
This type of inductance is the production of varying or alternating EMF (electromotive force) in one circuit by movement of magnetic flux lines of another nearby circuit with varying current across its conductors.
Metric prefix.
In engineering notation, a symbol used to represent a power of ten.
