TM 11-6625-599-12
GLOSSARY
Null- The condition wherein one value can-
cels the effect of another.
that measures an unknown voltage by com-
paring it with a known, variable voltage.
Resolution-The smallest increment that can
The difference, or differential, is indicated
be observed or measured.
b y a meter circuit. When the internal,
known voltage is varied until it is equal to
Sixty-Cycle Chopper-- A vibrating or oscillat-
the voltage being measured, as indicated by
ing device used to connect a circuit alter-
zero meter deflection, the unknown voltage
nately to two different circuits or points 60
is determined.
times per second. The contact arm is moved
by a coil energized by a 60-cps filament sup-
ply,
source of electromagnetic force when meas-
Voltage Excursion-- The deviation or variation
uring voltages.
of voltage about a given value, usually re-
Nominal Value- A usual or expected value,
ferred to in describing instability of dc volt-
not necessarily a specific or fixed value ex-
ages.
cept under given conditions.
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