DEMAG DC-Com 1 Operating Instructions Manual page 40

Before starting work, the electrical supply must be switched off. The mains connection or isolator switch must be
secured against unauthorized or accidental reconnection by means of a padlock.
Mechanical safety
All bolted connections must be correctly tightened.
Self-locking nuts must not be replaced by other types of nuts. Self-locking nuts must be replaced when they have
been tightened and untightened five times. The clamping torque of a self-locking nut must not be lower than the
screw-off torque specified by EN ISO 2320.
Only by tightening to the specific tightening torque can a sufficiently secure connection be guaranteed.
Bolted connections must not be lubricated as otherwise the specified tightening torque values will be too high.
Check that pin connections are properly secured.
All assembly work must be completed in accordance with the operating instructions and the hoist chain must be
greased. Operation with defective or damaged chains results in a high risk of accident for persons and the chain
hoist and is therefore prohibited.
Any change or modification which prejudices safety must immediately be reported to the nearest person responsible.
Repairs may only be carried out by experienced technicians.
Ensure that all suspension fittings are freely accessible for checks and inspections or that free access can be pro‐
vided.
The control device (e.g. control pendant) must be marked in such a way that the direction of movement is clear and
distinct. The arrow symbol on the control elements must correspond to the direction of movement.
Electrical safety
The chain hoist operating instructions must be referred to when Demag chain hoists are used.
These operating instrutions only contain standard circuit diagrams. Depending on the type of chain hoist an order-
specific circuit diagram may apply.
Protective earth conductor
The protective earth conductor in insulated leads and cables must be coloured green and yellow along its entire
length.
The protective earth conductor must not be connected to mounting bolts or screws.
Earth junctions and connections must be protected against self-loosening (e.g. by using serrated lock washers to
DIN 6798). It must be possible to disconnect each individual connection.
Protective earth conductors must not carry any current in operation
The same number of protective earth connection points must be provided as electrical power infeed and outfeed
points.
Continuity of the PE conductor connection must be checked.
Mains connection switch
A mains connection switch must always be provided for the main power supply line of the machine. This switch must
be arranged to disconnect all poles of the DC-Com chain hoist from the mains supply.
Ensure that the switch is installed in an easily accessible position near your machine and clearly marked.
Isolator switch
If two or more hoists are fed from a common main supply line, each one should be provided with an isolator switch.
This makes it possible to carry out maintenance work on individual hoists, without affecting operation of the rest of
the system.
Power supply system
The power supply line / cable to be used depends on the motor size, see section "Hoist motor data".
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