gain
The amplification factor of an amplifier circuit. Also the control in a signal follower which is used to adjust the follower to the maximum reference signal.

gate
The control element of an SCR or IGBT. For an SCR, when a small positive voltage is applied to the gate momentarily, the SCR will conduct current. Current will continue to flow even after the gate signal is removed. For an IGBT, a small positive voltage applied to the gate will cause the IGBT to conduct. Reversing this voltage causes the IGBT to stop conducting.

ground
(ground connection) The earth; an electrical connection to the ground. The return point in a circuit.

ground fault
A short circuit to ground.

ground fault protection
This circuit in an adjustable frequency drive senses a ground fault and immediately shuts off the drive. If any one of the output lines becomes grounded through a failure in the motor insulation or for any other reason, a large current spike will occur that will damage the drive unless it is protected by its own ground fault protection circuitry.