Hitachi L100 Jump Frequency, Line Reactor, Momentum, Motor Load, NEC, NEMA, Open-collector, Outputs, Power Factor, PID Loop, Process Variable

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L100 Inverter

Jump Frequency	A jump frequency is a point on the inverter output frequency range
	that you want the inverter to skip around. This feature may be used
	to avoid a resonant frequency, and you can program up to three
	jump frequencies in the inverter.
Line Reactor	A three-phase inductor generally installed in the AC input circuit of
	an inverter to minimize harmonics and to limit short-circuit current.
Momentum	The physical property of a body in motion that causes it to remain
	in motion. In the case of motors, the rotor and attached load are
	rotating and possesses angular momentum.

Multi-speed Operation The ability of a motor drive to store preset discrete speed levels for the motor, and control motor speed according to the currently selected speed preset. The Hitachi inverters have 16 preset speeds.

Motor Load	In motor terminology, motor load consists of the inertia of the
	physical mass that is moved by the motor and the related friction
	from guiding mechanisms. See also Inertia.
NEC	The National Electric Code is a regulatory document that governs
	electrical power and device wiring and installation in the United
	States.
NEMA	The National Electric Manufacturer’s Association. NEMA Codes
	are a published series of device ratings standards. Industry uses
	these to evaluate or compare the performance of devices made by
	various manufacturers to a known standard.

Open-collector Outputs A common logic-type discrete output that uses an NPN transistor that acts as a switch to a power supply common, usually ground. The transistor’s collector is open for external connection (not connected internally). Thus, the output sinks external load current to ground.

Power Factor	A ratio that expresses a phase difference (timing offset) between
	current and voltage supplied by a power source to a load. A perfect
	power factor = 1.0 (no phase offset). Power factors less than one
	cause some energy loss in power transmission wiring (source to
	load).
PID Loop	Proportional - Integral-Derivative - A mathematical model used for
	process control. A process controller maintains a process variable
	(PV) at a setpoint (SP) by using its PID algorithm to compensate for
	dynamic conditions and vary its output to drive the PV toward the
	desired value. For variable-frequency drives, the process variable is
	the motor speed. See also Error.
Process Variable	A physical property of a process that is of interest because it affects
	the quality of the primary task accomplished by the process. For an
	industrial oven, temperature is the process variable. See also PID
	Loop and Error.

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