Watlow PPC-2000 - Manual (Page 318)

Glossary PPC-2000 User’s Guide
290 Watlow Anafaze Doc.# 30002-00 Rev 2.3
T
Thermistor
A temperature-sensing device made of semicon-
ductor material that exhibits a large change in
resistance for a small change in temperature.
Thermistors usually have negative temperature
coefficients, although they are also available with
positive temperature coefficients.
Thermocouple (T/C)
A temperature sensing device made by joining
two dissimilar metals. This junction produces an
electrical voltage in proportion to the difference
in temperature between the hot junction (sensing
junction) and the lead wire connection to the
instrument (cold junction).
Tune
To set PID parameters on a closed-loop control
system.
V
Volt (V)
The unit of measure for electrical potential, volt-
age or electromotive force (EMF).
Voltage (V)
The difference in electrical potential between two
points in a circuit. It’s the push or pressure behind
current flow through a circuit. One volt (V) is the
difference in potential required to move one cou-
lomb of charge between two points in a circuit,
consuming one joule of energy. In other words,
one volt (V) is equal to one ampere of current (I)
flowing through one ohm of resistance (R), or
V=IR.