polarity of the signal being monitored
Duty Cycle
The ratio of the working time to the total time of a pulse train
expressed as a percent.
Elapsed Time
The period of time between the start of a measurement series to
the last measurement observed or recorded.
Electric Power
The measure of electric energy whose unit is the Watt.
E.g.: 1 Horsepower = 746 Watts. It is derived by multiplying the
applied voltage by the current passing through the circuit
Emissivity
A term related to temperature measurement using Infrared
radiation. Errors in IR measurements can occur based on the
color, shape, and presence of reflection on the measurement
surface. A wide emissivity adjustment should be available on a
IR thermometer to allow the user to compensate for these types
of errors.
EMF/Electromagnetic
Waves generated by a magnet configuration usually consisting of a
Radiation
coil wound around a steel core. The core is strongly magnetized
when current flows through the coil. Video Monitors, power lines,
and wire harnesses are a few of the devices which produce electro-
magnetic radiation.
Glitch Capture
The ability of an instrument to listen for and capture spikes that
occur in signals. The resulting captures are usually sent directly to
the screen for display.
Go/No Go Alarm
An output from a meter or controller which is used to indicate
when a preset measurement point has been reached or exceeded.
On the tpi 460, the continuity checker is a form of Go/No Go alarm
Kelvin Connection
A four wire method of connecting test leads which is designed to
eliminate or greatly reduce the effect of lead and contact resistance
and thus permitting accurate measurements of low resistance.
LCD
Acronym for Liquid Crystal Display. Liquid crystal is a liquid that
is not isotopic, that is, it forms patterns when polarized. The
orientation of the molecules of the liquid are arranged by the
meter to form the display.
LED
Acronym for Light Emitting Diode. An electric current is passed
through the diode causing illumination. When used for alpha-
numeric display purposes, the LED’s usually have seven segments
460 User’s Guide
Glossary
C-3
