Test Products International 460 - Manual (Page 51)

differ electrically they will effect metering. The most common
electrical difference is a change in attenuation. tpi probes typically
come with attenuations of either 1:1 or 10:1.
Probe Adjust For the meter to read accurately, the DUT and input capacitances
should match. Probe adjust allows a capacitance compensation to
be made whenever a change of probes or oscilloscope input
is made.
Psychrometers A relative humidity measuring device which has two thermometers.
(Wet Bulb) One of the thermometers measures ambient temperature (dry
bulb), the second measures the temperature of an element
surrounded by a fibrous material saturated with water (wet bulb).
Reference tables are than used to determine relative humidity.
Real Time Update The tracking of events as they happen.
Recall Mode To bring back from memory and display a previously recorded
waveform.
Resolution The smallest value a display device can indicate. For example, if a
device can display 0.0 to 100.0 RPM, the smallest measurement,
and therefore the resolution, is 0.1 RPM
Response Time The rate at which a measuring device responds to a change in the
measured variable
RH Capacitance Probe A capacitive device that senses relative humidity The meter used
with such a probe senses the change in capacitance based on the
moisture encountered by the capacitor’s dielectric and displays the
relative humidity based on this capacitance value.
RH Resistance Probe A resistive device that senses relative humidity The meter used
with such a device monitors the resistance of the probe which
changes proportionally to the amount of moisture encountered.
The meter then displays the relative humidity based on this
resistive value.
RMS See “True RMS”
RTD A temperature measurement device whose resistance is
proportional to temperature.
Single Phase A single alternating current source such as a typical AC wall outlet.
Three-phase on the other hand, provides three separate alternating
460 User s Guide Glossary
C-5