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Nano--(n)
A metric prefix meaning one billionth of a unit or 10-9.
NEMA
National Electrical
Manufacturers Association.
NEC
National Electrical Code.
Neutral
The grounded junction
point of the legs of a wye circuit. Or, the grounded center point of one
coil of a delta transformer secondary. Measuring the phase to neutral
voltage of each of the normal three phases will show whether the system is
wye or delta. On a wye system, the phase to neutral voltages will be
approximately equal and will measure phase to phase voltage divided by 1.73.
On a center tapped delta system, one phase to neutral voltage will be
significantly higher than the other two. This higher phase is often called
the "high leg".
Neutralizing Winding
An extra
winding used to cancel harmonics developed in a saturated secondary winding,
resulting in a sinusoidal output waveform from a ferroresonant transformer.
Nominal Voltage
The normal or
designed voltage level. For three phase wye systems, nominal voltages are
480/277 (600/346 Canada) and 208/120 where the first number expresses phase
to phase ( or line to line) voltages and the second number is the phase to
neutral voltage. The nominal voltage for most single phase systems is
240/120.
Non-inductive Circuit
A circuit
in which the magnetic effect of the current flowing has been reduced by one
several methods to a minimum or to zero.
Non-linear Load
A load where the
wave shape of the steady state current does not follow the wave shape of the
applied voltage.
Null
Zero
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