Altec DRM 12, Руководство пользователя

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Appendix — Glossary
mercury switch — a switch that is closed or opened when an inter-
nal globule of mercury moves to or away from the contacts when the
switch is tilted.
meter — to regulate the amount of fluid flow.
meter-in — to regulate the amount of fluid flow into an actuator or
system.
meter-out — to regulate the flow of the discharge fluid from an actua -
tor or system.
micron (micrometer) — one-millionth of a meter or about 0.00004 ″ .
micron rating — the minimum size of the particles that a filter is
designed to remove.
microswitch
— a small electrical device that is used to turn an electrical
current on or off, or to change the connections in a circuit.
minimum approach distance — the three dimensional area sur-
rounding a conductor into which a person may not enter nor bring any
conductive object unless they are: qualified electrical workers, wearing
insulating gloves (and sleeves when required), protected against contact
with any other objects at a different electrical potential.
mobile operation — the use of the aerial device or digger derrick while
the mobile unit is traveling.
mobile unit — the combination of a unit, its chassis and related per-
manently attached equipment.
modified A-frame outrigger — an extendible outrigger that is config -
ured like a large broad based “A” with an open top.
modulation ratio — the “on” time vs. the “off” time of a pulse width
modulated digital signal. This ratio is determined by dividing the on
time during one cycle by the total cycle time.
moly — see molybdenum disulfide.
molybdenum disulfide — a black inorganic chemical that is used as
a dry lubricant and as an additive for grease and oils. Molybdenum
disulfide has a very high melting point and is insoluble in water.
molydisulfide — see molybdenum disulfide.
moment — a force multiplied by the perpendicular distance from the
line of action of the force to an axis or point. The force may be the
weight of an item, with the vertical line of action located at the item’s
center of gravity. Moment is measured in units of force times distance;
for example, pound-feet or foot-pounds.
monitor head — remotely controlled articulated assembly with a nozzle,
mounted at the upper end of an HLIW.
motor — a device that converts hydraulic or electrical energy into
continuous rotary motion and torque.
multiple-part line — the arrangement of the winch line in which the
winch line is routed between the boom tip and the load two or more
times. A snatch block is used at the load and a snatch block or additional
boom tip sheave(s) is used on the boom to reverse the direction of
the winch line. The end of the winch line is connected to a stationary
attachment point on the boom or lower snatch block. A multiple-part
line is used to reduce the tension in the winch line to a value below
the winch line rated working load when a lifting load that exceeds the
winch line rated working load.
multiplexing — a process by which signals from multiple inputs are
combined and transmitted simultaneously over a single channel.
multiviscosity — the viscosity characteristic of a fluid which contains
additives that increase the viscosity index. The fluid does not become
as thin at high temperatures or as thick at low temperatures as a fluid
without these additives. This allows the fluid to be used over a wider
temperature range.
nonconductive
— the characteristic of a substance that allows it to
transmit electricity only in a very small degree when it is clean, dry and
properly maintained.
noncontinuous rotation — a rotation system in which the turntable is
prevented from rotating more than approximately one revolution about
the centerline of rotation.
non-insulating aerial device or digger derrick — an aerial device
or digger derrick which is not designed, manufactured, or tested to
meet any dielectric rating.
nonmetallic — formed of materials which are not any type of metal.
non-overcenter aerial device — a type of articulating-boom aerial
device on which the upper boom will not unfold from the stored posi-
tion to beyond a vertical position regardless of the position of the
lower boom.
lower arm — the primary load-carrying structure of a double elevator
which is located between the lower pedestal and the riser.
lower arm cylinder — the hydraulic cylinder that moves the lower arm
of a double elevator up and down.
lower boom (LWR BOOM) — the boom section in a boom assembly
which is attached to the turntable or riser, and which supports the upper
boom or intermediate boom.
lower boom cylinder — the hydraulic cylinder that moves the lower
boom about its pivot point on an articulating-boom aerial device.
lower boom insulator — the part of the lower boom made of high
dielectric strength material (usually fiberglass reinforced plastic or
equivalent) to interrupt the conductive path for electricity through the
lower boom.
lower boom winch — a winch that is located on the lower boom.
lower control valve — the hydraulic valve on the vehicle, turntable,
or pedestal of an aerial device used for operating some or all of the
functions of the aerial device.
lower controls — the controls on the vehicle, turntable, or pedestal,
used for operating some or all of the functions of the unit.
lower pedestal — the structure within an elevator lift that connects
the elevator lift to the subbase.
lower test electrode system — a system on an insulating aerial
device utilizing conductive bands installed permanently on the inside
and outside surfaces of the insulating portion of the upper boom and
conductive connections to components inside that portion of the boom
such as leveling rods and hydraulic lines. All the bands and component
connections are connected to a common pickup point for use in mea -
suring current leakage to confirm of dielectric integrity.
lower tool circuit — a hydraulic tool circuit with quick disconnect
couplings located on the pedestal or on the vehicle.
lug — a metal part which serves as a cap, handle, support, or fitting
connection.
lunette eye — a round metal ring used in place of a ball coupler on a
trailer. It attaches to a pintle hook on the towing vehicle.
magnetic suction separator filter — see magnetic suction strainer.
magnetic suction strainer — a suction filter consisting of a strainer
which contains one or more magnets to trap ferrous metallic contami-
nants that are small enough to pass through the strainer.
mainframe — see pedestal.
man-and-a-half platform
— an oversized one-man platform.
manifold — a fluid conductor that provides multiple connection
ports.
manual lowering valve — a manually operated hydraulic valve used
to lower the boom in the event of power failure.
manual override — a means of manually actuating an automatically
or remotely controlled device.
manually extendible jib — a jib that is capable of being extended and
retracted by human force.
mast — the structure on a pressure digger which supports the auger
transmission gearbox, ram cylinder, kelly bar, and pole setter.
master control panel — the primary derrick lower control panel which
contains the electrical connections between the derrick control system
and components such as the power module and the dump or blocking
valve. The master control panel is used in conjunction with a slave
panel to provide dual station lower controls.
master cylinder — a cylinder in which motion of the piston under an
external force transfers hydraulic fluid to a slave cylinder to produce
corresponding motion.
material handling — having the ability to use the boom or attachments
on the boom to lift and position materials.
material handling system — the system on an aerial device that
consists of a jib and winch used to lift material to the upper boom tip.
mechanical leveling system — a mechanical system which keeps
the bottom of a platform parallel to or at a fixed angle to the turntable
base plate as the boom is raised or lowered. One means of accom-
plishing this is by utilizing a parallelogram arrangement of leveling rods
attached to cables or chains operating around sheaves or sprockets
at boom pivot points.