Tadano TT-800XXL1, Руководство по обслуживанию

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H-1. H-1.
Safety System
1
WH02-0080E
Safety System
1 . General
1 . 1 Pressure sensor
1 . A retraction pressure sensor and an extension
pressure sensor are incorporated in the elevating
cylinders.
2. They convert the elevation pressure into the
electric signal and transmit it to the moment limiter
main body, making the limiter calculate the total
moment created by the lifted load and the mass of
the boom.
1 .2 Boom length and angle detector
The Boom length and angle detector is installed
on the boom side, and uses the potentiometer
inside the detector to convert the extended boom
length and the angle of the boom relative to the
ground into an electric signal that is transmitted to
the moment limiter main body.
1 .3 Outrigger extension width detector
It is installed on the rear end of the outrigger outer
case. The potentiometer in the detector converts
the outrigger extension width into the electric
signal and transmits it to the moment limiter main
body.
1 .4 Other detectors and switches
The outer detectors and switches convert the
crane operation modes and working conditions
into an electric signal that is transmitted to the
moment limiter main body.
1 .5 Moment limiter (AML-L) main body
1 . The moment limiter maln body calculates the
moment being generated on the crane based on
signals from the pressure sensor and the Boom
length & angle detector.
2. The calculation result is compared with the rated
moment and,when it reaches 90% and 1 00% of
the rating,the moment limiter sends alarm and
auto. stop signals, respectively, to prevent the
crane from being overloaded.
1 .6 Auti-twoblock Device
The anti-twoblock device prevents damage to the
crane that would be caused by pulling the hook
block into the boom head. When the hook block
approaches the boom head, single top or jib, the
anri-twoblock device sends a signal to the AML
(load moment indicator), which then stops any
further crane action toward the critical condition.
1 .7 Solenoid valve
1 . If the AML malfunctions or if the actual moment
reaches 1 00% of the rated moment or the hook
block is over-hoisted, an electric signal (auto.
stop) is sent from the moment limiter main body to
this valve.
2. When the solenoid valve is deenergizied, this
solenoid valve contents the vent line of the relief
valve mounted on the hydraulic pilot control valve
to the tank. The solenoid valve by allowing the
pressurized oil from the pump to escape through
the relief valve to the tank, therefore the crane
operation stops.
2. Description of system
Refer to the repair manual for the AML-L.