Manitowoc Grove GMK 4100L-1, Operating Manual

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Crane operation
11.5 Crane operation with main boom
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GMK4100L-1
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1.
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11.5.4
Lifting limit switch and lowering limit switch
Lifting limit switch To install/remove the lifting limit switch;
à
p. 12 - 120.
The lifting limit switch ( 1 ) prevents the hook block being lifted up to the
main boom head and damaging it.
The lifting limit switch only works if it has been unlocked;
à
p. 12 - 125.
The lifting limit switch will be triggered if:
( A ) – the hook block raises the lifting limit
switch weight or
( B ) – the lifting limit switch weight touches the
ground upon lowering or
( C ) – the lifting limit switch weight is not
attached.
The lifting limit switch will not trigger if it is
locked.
The lamp ( 1 ) will light up if the lifting limit switch has been triggered.
At the same time, all movements which would increase the load moment
will be switched off –
Lifting , Lowering, Extending and Derricking the lattice
extension if necessary.
To cancel the shutdown, leave the shutdown range by performing a
different crane movement or by setting down the load.
G
Risk of accidents due to intentionally triggering the lifting limit switch
Always complete the hoisting operation (and extending) before raising the
lifting limit switch weight. If the lifting limit switch is lifted at too great a
speed, the hook block may swing into the main boom head and damage the
head sheaves and the hoist rope.