Rice Lake Weigh Modules/Mount Assemblies - Manual (Page 83)

G-7
GLOSSARY
TERMINAL RESISTANCE, Corner
to Corner
The resistance of the load cell circuit measured
at specific adjacent bridge terminals at standard
temperature with no load applied and with the
excitation and output terminals open-circuited.
TERMINAL RESISTANCE, Input
(Excitation)
The resistance of the load cell circuit measured
at the excitation terminals at standard
temperature with no load applied and with the
output (signal) terminals open-circuited.
TERMINAL RESISTANCE, Output
(Signal)
The resistance of the load cell circuit measured
at the output signal terminals at standard
temperature with no load applied and with the
excitation terminals open-circuited.
TOLERANCE
The amount of error that is allowed in a value.
It is usually expressed as a percent of nominal
value, plus or minus so many units of
measurement.
TRACEABILITY
The step-by-step transfer process by which the
load cell calibration can be related to primary
standards.
TRANSDUCER
A device that converts energy from one form to
another.
TRANSIENT
A momentary surge on a signal or power line. It
may produce false signals or triggering
impulses and cause insulation or component
breakdowns and failures.
TRIAC
A three-terminal, gate controlled, bidirectional
silicon switching device that can switch either
alternating or direct currents.
TRIM
To make a fine adjustment, as of load cell
outputs in a multicell system.
V
v
min
(Minimum Verification Scale
Division/Load Cell)
A parameter used to select load cells for NTEP
approved applications. For single cell applica-
tions, v
min
must be less than or equal to the
scale division size; for mechanical scale
conversions using one load cell, v
min
must be
less than or equal to the scale division size
divided by the scale multiple. For a scale using
more than one load cell, v
min
must be less than
or equal to the scale division divided by the
square root of the number of cells.
VOLATILE MEMORY
A computer storage medium whose contents
are lost when there is a loss of power.
VOLT
The unit of voltage, potential difference and
electromotive force. One volt will send a
current of one ampere through a resistance of
one ohm.
VOLTAGE
The electrical potential difference that exists
between two points and is capable of producing
a flow of current when a closed circuit is
connected between the two points.
VOLTAGE DIP
A temporary decrease in voltage level lasting at
least one alternating current cycle.
VOLTAGE SPIKE
Large damaging voltage pulse caused when
lightning strikes a power line, communication
line, a signal or sensing line, or even the
ground nearby.
VOLTAGE SURGE
A temporary rise in voltage level lasting at least
one alternating current cycle.
W
WATER-PIPE GROUND
An earth connection made by running a strong
wire to the nearest cold water pipe.
WATER TIGHT
An enclosure so constructed that moisture will
not enter the enclosure under specified test
conditions.
WEATHER PROOF
An enclosure so constructed or protected that
exposure to the weather will not interfere with
successful operation of its contained equip-
ment.
WEIGHT
The force or amount of gravitational pull by
which an object or body is attracted toward the
center of the earth.
Z
ZENER DIODE
A semiconductor diode which is used in the
reverse biased condition. It exhibits a nonde-
structive breakdown at a predetermined reverse
voltage, so while the diode is operating in this
breakdown region, an increase in current flow
through the diode will not result in increased
voltage drop across the diode. It is used in
voltage regulation circuits and as a voltage
limiting device in intrinsic safety barriers.
ZERO BALANCE
The output signal of the load cell with rated
Excitation and with no load applied, usually
expressed in percent of Rated Output.
ZERO RETURN
The difference in Zero Balance measured
immediately before Rated Load application of
specified duration, measured after removal of
the load, and when the output has stabilized.
ZERO SHIFT, Permanent
A permanent change in no-load output.
ZERO STABILITY
The degree to which the load cell maintains its
Zero Balance with all environmental conditions
and other variables remaining constant.