Kato SR-300L, Instruction Manual

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18-2 Boom derricking and lowering
(4210-3247-0E)
: Set the crane operation switch to the "ON" position and push the right control lever left to derrick the boom.
: Set the crane operation switch to the "ON" position and push the right control lever right to lower the boom.
When the boom is long or the jib fitted, the crane will tip over if the boom is lowered below the
critical angle even if there is no suspended load. Refer to Service data to find the critical angle.
(4210-0039-1E)
Precautions on derricking and lowering the boom
・ Work the lever gently.
Sudden lever operation causes strong shocks in the structure of the crane, particularly when a
load is suspended, so work with care.
・
The working radius increases as the boom lowers, possibly causing an overload which could
tip the crane, so proceed with caution.
・ Never try to drag a load sideway or toward the crane by derricking the boom.
・
Rapid, careless derricking and lowering of the
boom causes the hook to swing and strike the
underside of the boom, making dents and
deformation which harm the boom. Be
particularly careful when the boom angle is
large and when the hook is close to the boom
top.
(4210-0040-0E)