ISOCHRONOUS-- Mode of governor operation
HERTZ (Hz)-- A unit of frequency equal to one
normally used for generator operation. This
cycle per second.
mode provides a constant frequency for all load
conditions. When operating two or more
HORSEPOWER (hp)-- The English unit of power,
generators in parallel, use of the isochronous
equal to work done at the rate of 550
mode also provides equal load sharing between
foot-pounds per second. Equal to 746 watts of
units.
electrical power.
K
HOT WIRE METER MOVEMENT-- A meter
movement that uses the expansion of heated
KILO-- A prefix meaning one thousand.
wire to move the pointer of a meter; measures
dc or ac.
KINETIC ENERGY-- Energy that a body possesses
by virtue of its motion.
HYDROMETER-- An instrument used to measure
specific gravity. In batteries, hydrometers are
KIRCHHOFF'S LAWS-- (1) The algebraic sum of
used to indicate the state of charge by the
the currents flowing toward any point in an
specific gravity of the electrolyte.
electric network is zero. (2) The algebraic sum
of the products of the current and resistance in
HYSTERESIS-- The time lag of the magnetic flux in
each of the conductors in any closed path in a
a magnetic material behind the magnetizing
network is a equal to the algebraic sum of the
force producing it, caused by the molecular
electromotive forces in the path.
friction of the molecules trying to align
themselves with the magnetic force applied to
L
the material.
LEAD-ACID CELL-- A cell in an ordinary storage
H Y S T E R E S I S L O S S -- The power loss in an
battery, in which electrodes are grids of lead
iron-core transformer or other ac device as a
containing an active material consisting of
result of magnetic hysteresis.
certain lead oxides that change in composition
during charging and discharging. The electrodes
I
or plates are immersed in an electrolyte of
diluted sulfuric acid.
INDUCED CURRENT-- Current caused by the
relative motion between a conductor and a
LINE OF FORCE-- A line in an electric or magnetic
magnetic field.
field that shows the direction of the force.
INDUCED ELECTROMOTIVE FORCE-- The
LOAD-- (1) A device through which an electric
electromotive force induced in a conductor
current flows and that changes electrical energy
caused by the relative motion between a
into another form. (2) Power consumed by a
conductor and a magnetic field. Also called
device or circuit in performing its function.
INDUCED VOLTAGE.
M
INDUCTIVE REACTANCE-- The opposition to the
flow ac current caused by the inductance of a
MAGNETIC FIELD-- The space in which a magnetic
circuit, expressed in ohms and identified by the
force exists.
symbol
MAGNETIC POLES-- The section of a magnetic
INSULATION-- (1) A material used to prevent the
where the flux lines are concentrated; also
leakage of electricity from a conductor and to
where they enter and leave the magnet.
provide mechanical spacing or support to
protect against accidental contact. (2) Use of
material in which current flow is negligible to
MAGNETISM-- The property possessed by certain
surround or separate a conductor to prevent loss
materials by which these materials can exert
of current.
mechanical force on neighboring masses of
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