Hitachi L100 Torque, Transistor, Trip, Watt Loss

A–8

Bibliography

Appendix A

Torque	The rotational force exerted by a motor shaft. The units of measure-
	ment consist of the distance (radius from shaft center axis) and
	force (weight) applied at that distance. Units are usually given as
	pound-feet, ounce-inches, or Newton-meters.
Transistor	A solid state, three-terminal device that provides amplification of
	signals and can be used for switching and control. While transistors
	have a linear operating range, inverters use them as high-powered
	switches. Recent developments in power semiconductors have
	produced transistors capable of handling high voltages and currents,
	all with high reliability. The saturation voltage has been decreasing,
	resulting in less heat dissipation. Hitachi inverters use state-of-the-
	art semiconductors to provide high performance and reliability in a
	compact package. See also IGBT and Saturation Voltage.
Trip	An event that causes the inverter to stop operation is called a “trip”
	event (as in tripping a circuit breaker). The inverter keeps a history
	log of trip events. They also require an action to clear.
Watt Loss	A measure of the internal power loss of a component, the difference
	between the power it consumes and what its output delivers. An
	inverter’s watt loss is the input power minus the power delivered to
	the motor. The watt loss is typically highest when an inverter is
	delivering its maximum output. Therefore, watt loss is usually
	specified for a particular output level. Inverter watt loss specifica-
	tions are important when designing enclosures.

Bibliography

Title	Author and Publisher
Variable Speed Drive Fundamentals, 2nd Ed.	Phipps, Clarence A.
	The Fairmont Press, Inc. / Prentice-Hall, Inc. 1997
	ISBN 0-13-636390-3
Electronic Variable Speed Drives	Brumbach, Michael E.
	Delmar Publishers 1997
	ISBN 0-8273-6937-9
Hitachi Inverter Technical Guide Book	Published by Hitachi, Ltd. Japan 1995
	Publication SIG-E002