Reference: 38741
Issue date: 2018-JUL-24
Revision: L
Page 33 of 37
12. Safety Features
1. Automatic slack rope safety device
The automatic slack rope safety device locks mechanically onto the safety rope if the
suspension rope loses tension or breaks.
2. Overload detection device
The overload detection device of each hoist is factory
set to stop the ’up’ direction of travel if
the Working Load Limit (WLL) of the hoist is exceeded by 25%.
The RED warning light on the Central Control Box (CBB) will come ON in case of overload.
The overload detection devices of both hoists are connected in series. If one overload
detection device is triggered, then the up movement of both hoists is halted.
To release the overload detection device, remove the excessive load.
Tip: In addition to removing the excessive load, it may be required to remove part of the normal
load in order to reset the overload detection device. Once the overload detection device is
reset, the platform can once again be loaded with the full normal load
.
3.
‘No-Power’ descent
In the event of a power failure the platform can be lowered at a controlled speed
(Approx.
6 m/min.), by pulling the ‘No-Power’ descent lever on the electro-magnetic service
brake.
Warning: Never use the emergency manual descent when normal powered movement is
possible.
4. Top limit switch
The Top limit switch cuts the up movement when it is activated by the striker plate, which is
clamped onto the safety rope at the top of travel.
When the Top limit switch is triggered, the platform can be driven down but not up.
The Top limit switches of both hoists are connected in series. If one Top limit switch is
activated, then the ‘up’ movement of both hoists is halted.
5. Phase Protector (for three phase hoist ONLY)
All three phase Central Control Boxes are fitted with a phase protector, which cuts power
supply if phases are reversed. When the phases are
correctly connected, the GREEN ‘OK’
indicator light on the outside of the CBB, AND the GREEN indicator light on the phase
protector (only visible when CBB is opened) are ON and the hoists will operate.
If indicator lights are OFF, use a screwdriver to reverse the phases in the phase reversal power
plug of the CCB.
WARNING:
DO NOT
change any connections in the central control
box.
