Gain: The ratio of system output signal to system input signal.
Gate: The control element an SCR (silicon controlled rectifier) commonly referred to as a thyristor. When a small positive voltage is applied to the gate momentarily, the SCR will conduit current ( when the anode is positive with respect to the cathode of the SCR). Current conduction will continue even after the gate signal is removed.
Gear Ratio: In gearboxes and gearmotors, the gear ratio is derived by dividing the input speed by the output speed.
Gear Types - Inline Reducer: A gearbox in which the input and output shafts are in a straight line.
Gear Types - Parallel Shaft: A gear box in which the input and output shafts run in parallel to each other.
Gear Types - Planetary: A specialized speed reducer in which the self-aligning gear train floats to evenly distribute all internal loads. This design is used for demanding high shock load applications.
Gear Types - Right Angle: A gear box in which the input and output shafts run at right angles to each other.
Gear Types - Worms: A type of gear box in which the gear teeth mesh with a threaded shaft called the worm when operating.
Gears - Bevel: Gears which are made in a beveled shape.
Gears - Helical: Gears which are made in a helical shape.
Gears - Herringbone: Gears which are made in a herringbone shape.
General Purpose Motors: Motors as defined by NEMA which have certain operating characteristics that make them applicable for operation of many type of driven equipment.
Generator Action of an Induction Motor: An induction (squirrel cage) motor acts as a generator in 2 different ways: (1) Generally the rotor acquires some residual magnetism (especially if DC current is applied to the stator for dynamic braking). In this case the rotor causes generator action in the stator for several seconds. That is, with the line switch quickly opened, a voltage remains across the motor terminals from 1/2 second to several seconds, diminishing with the decrease in motor speed. (2) A induction motor driven above its rated speed delivers leading power factor current back into the line -- it must derive its exciting current from the line. This is a very simple form of generation of power and for certain power systems is an almost ideal method of increasing line capacity.
GTO: Gate turn-off or gate turn-on power semiconductor device.
Guide Bearing: A bearing on vertical motors which acts as the guide in shaft alignment.
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