Kickback And Other Reactive Forces; Reactive Forces - Stihl HTA 50.0 Instruction Manual

7 Kickback and Other Reactive Forces

￭
2
1
￭ To reduce the risk of severe or fatal personal injury from
loss of control when cutting wood under tension:
– Always start with a relieving cut (1) at the
compression side (A) of the branch, and then make
a cross-cut (2) at the tension side (B).
– If a pinch occurs that traps the bar/chain, switch off
the motor, remove the battery and remove the pole
pruner from the branch, exercising caution that the
limb does not suddenly snap or release.
DANGER
￭ Electricity can jump from one point to another by means of
arcing. Higher voltage increases the distance electricity
can arc. Electricity can also move through branches,
especially if they are wet. To reduce the risk of
electrocution:
– Never operate this pole pruner in the
vicinity of any wires or cables that may
be carrying electric current. Look
carefully for concealed wires before
starting work.
– Never cut near power lines.
– Hold the power tool only at the
designated gripping surfaces, but do not
rely on them for protection against
electric shock. This pruner is not
insulated.
0458-813-8221-A
B
A
– Maintain a clearance of at least
– Before working with less
7 Kickback and Other Reactive Forces
7.1

Reactive Forces

WARNING
￭ Reactive forces may occur any time the chain is rotating.
Reactive forces can cause serious or fatal personal injury.
￭ The powerful forces used to cut wood can be reversed and
work against the operator. If the rotating saw chain is
suddenly and significantly slowed or stopped by contact
with any solid object such as a branch, or is pinched, the
reactive forces may occur instantly.
￭ These reactive forces may result in loss of control, which,
in turn, may cause serious or fatal injury.
– An understanding of the causes of these reactive
forces may help you avoid the element of surprise
and loss of control. Surprise contributes to
accidents.
￭ Because of the design of the pole pruner, the reactive
forces experienced when working with it are generally not
as severe as those encountered with a chain saw.
– Nevertheless, always maintain a proper grip and
good footing to control the pole pruner when you
experience such forces.
The most common reactive forces are:
– Kickback
English
50 ft. (15 m) between the pole
pruner (including any branches
it is contacting) and any
electrical line carrying live
current.
clearance, contact your electric
utility and make sure the current
is turned off.
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