Bosch VLE 21 Series, Repair Instructions

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1 689 975 224 2013-11-06
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Robert Bosch GmbH
48 | VLE 21xx | Faults and remedial action en
11. Faults and remedial action
!
In the event of problems, the lifting platform is to be
immediately de-energised, shut down and secured
against unauthorised use and Bosch customer
service must be informed.
!
Repair work on Bosch lifting platforms is only to
be performed by authorised customer service
personnel. Exclusive use is to be made of genuine
Bosch spare parts. The use of parts from other
manufacturers renders the type approval invalid.
Noise during lifting and lowering
Cause: Lack of lubrication, worn spindle mount, slack
V-belts, slack chain.
Remedy: Lubricate the spindles. Replace the spindle
mounts if defective. Re-tension (replace) the chain.
Re-tension (replace) V-belts.
Electrical switch-on of lifting platform no longer
possible
Remedy: Check operation of the load current switching
elements and the motor. Check the master switch, the
control circuit, the miniature fuse and the chain break
switch as well as checking the thermoswitch in the
motor winding for continuity.
Lifting platform does not lift the load or "humming"
of motor
Remedy: Check whether the permissible lifting platform
loadbearing capacity has been exceeded.
Check lubrication between loadbearing nut and spindle.
Check whether voltage is being applied at all three
phases of the wiring to the electric motor, check the
contactor contacts, check V-belts.
Lifting carriage/lifting platform is only raised by
approx. 100 mm
Remedy: Check the safety system. The loadbearing
nut is probably worn and the lifting platform is being
switched off mechanically by the raising bracket,
i.e. the mechanical anti-raise safety device is in
operation.
Shut down the lifting platform immediately, secure
against unauthorised use and call in Bosch customer
service.
Swivel arm locking mechanism not functioning
Remedy: Check the locking elements, check the
pressure springs between the locking element and
lifting carriage side wall, check the locking rods for
proper attachment and damage.
Lower and upper cut-out points not reached
Remedy: Refer to Commissioning "Setting cut-out
points".
Control system failure
Remedy:
1.
Set the master switch to "0".
2. Remove the cover from the switch box and perform
emergency lowering.
Call in Bosch customer service in the event of faults not
covered by the above.
Excessive lifting carriage overtravel after switch-off
(VLE 2130 EL and VLE 2140 EL)
Remedy:
1.
Check the mechanical flyweight reduction for friction
element wear.
2. There is a hole in the friction element guide. A new
friction element is to be fitted if the bottom edge of
the friction element is visible.
3.
Pre-tighten the hexagon bolts to a torque of 1.2 Nm
and then secure with a lock nut.