FUNCTIONING PRINCIPLES
Figure 1: INSTALLATION OF THE ROPE
The descender can either be attached to the harness concordant with either
EN 361, EN 813 or EN 12277 (fig.4
/A -
the operator slides with the descender
along the rope) or it can be fastened to an anchor (fig.
4/C
– the rope slides
through the non-moving descender). To install the descender on the rope,
first form a bight on the rope (
fig.1/B
). The handle of the descender has to be
pushed in its extreme open position and the jamming cleat has to be drawn
out of the descender to its terminal point. Now the bight can be pushed in
between both flanges at their lower end (
fig.1/A
), that is, between the
attachment point
and the jamming cleat. Care should be taken that the
working (load carrying) end of the rope exits the device
by the jamming cleat
and the free end of the rope by the carabiner. Then thread the bight around
the jamming cleat, between the upper parts of bot
h
flanges and finally catch
the jamming cleat with the bight.
Eventually move the jamming cleat back in
the descender so that it engages the rope. If the rope has not been inserted
correctly the descender will not be able to perform its function and will hence
be of no use.
F
igure 3: OPERATIONAL CHECK
Before each use carry out an operational check of the device by testloading it
with your body weight while secured by other means. Additionally it is
essential to assess the reliability and security of the entire safety system you
are relying on: adequate resistance of the anchors (EN 795 or ANSI/ASSE
Z359.1 for fall-arrest and 3100 lb for static loads) and their correct (higher)
positioning to arrest a fall and prevent pendulum effects, correct positioning
of the ropes – e.g. protecting sharp edges or points of rubbing, preventing ill
running of the descender, redundancy, etc. – and to tie a stopper knot at the
free end of the rope. Any overload or dynamic loading of the descender may
damage the rope. Avoid descending into electrical, thermal or chemical
sources or hazards.
F
igure 4: DESCENT
W
hile loading the system, the user should hold with one hand the free end of
the rope and with the other hand gradually p
ush
the handle against the
descender's body (
fig.4
/A). This unblocks the rope and allows for a
controlled descent. The maximal permitted speed of descent is 2 m/s. By
increasing pressure on the handle the user will activate the descender's
second braking position (anti panic) and when the pressure is high enough
the descent will be stopped entirely (
fig.
4/
B
). By releasing the handle
altogether the descent is stopped automatically
(fig.2/A)
. Use a second
braking carabiner to lower from a
fixed position (
fig.
4/
C).
To prevent
accidental uncontrolled descents, the descender
may be locked-off entirely
by forming a bight in
the free end
of
the rope, passing it through the
connecting
carabiner and
c
atching with
the
b
ight the entire descender
(
fig.
4/
D
).