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7.3 Switching on / off
In the event of motor overload due to application of
excessive pressure to the disc, performance will drop
noticeably or the power tool may stop running (avoid
stalling the power tool in this way). Permissible tool
overload cannot be given as a specific value as it depends
on the temperature of the motor. If the power tool has
been overloaded, release the pressure applied and then
allow it to run under no load for approx. 30 seconds.
7.3.1 Switching on (AG 450‑7S)
1. Plug the supply cord into the power outlet.
2. Press the rear section of the on / off switch.
3. Slide the on / off switch forward.
4. Lock the on / off switch.
7.3.2 Switching off (AG 450‑7S)
Press the rear section of the on / off switch. The on / off
switch jumps back to the off-position.
7.3.3 Switching on (AG 450‑7D)
8
The hold-to-run switch with built-in safety interlock en-
ables the user to check the switch function and prevents
inadvertent starting of the power tool.
1. Plug the supply cord into the power outlet.
2. Press the safety interlock to unlock the hold-to-run
switch.
3. Press the hold-to-run switch fully.
7.3.4 Switching off (AG 450‑7D)
When the hold-to-run switch is released, the safety inter-
lock returns automatically to the locked position.
8 Care and maintenance
CAUTION
Disconnect the mains plug from the power outlet.
8.1 Care of the power tool
DANGER
When working on metal under extreme conditions, con-
ductive dust may accumulate inside the power tool. This
may negatively affect the power tool’s protective in-
sulation.
Under such conditions, the tool should be
plugged into a ground fault circuit interrupter (GFCI)
and use of a stationary dust removal system and
frequent cleaning of the tool’s cooling air slots is
recommended.
The outer casing of the power tool is made from impact-
resistant plastic. Sections of the grip are made from a
synthetic rubber material.
Never operate the power tool when the air vents are
blocked. Regularly clean the power tool’s air vents care-
fully with a dry brush. Do not permit foreign objects to
enter the interior of the tool. The motor’s fan will draw
dust into the casing and an excessive accumulation of
conductive dust (e.g. metal, carbon fiber) may cause
electrical hazards. Clean the outside of the power tool at
regular intervals with a slightly damp cloth. Do not use
a spray, steam pressure cleaning equipment or running
water for cleaning. This may negatively affect the elec-
trical safety of the tool. Always keep the grip surfaces
of the tool free from oil and grease. Do not use cleaning
agents which contain silicone.
NOTE
Frequent work on conductive materials (e.g. metal, car-
bon fiber) may make shorter maintenance intervals nec-
essary. Take your individual work place risk assessment
into account.
8.2 Maintenance
WARNING
Do not operate the tool if parts are damaged or when
the controls do not function faultlessly. If necessary,
the power tool should be repaired by Hilti Service.
WARNING
Repairs to the electrical section of the power tool may
be carried out only by trained electrical specialists.
Check all external parts of the power tool for damage
at regular intervals and check that all controls operate
faultlessly.
8.3 Checking the power tool after care and
maintenance
After carrying out care and maintenance work on the
power tool, check that all protective and safety devices
are fitted and that they function faultlessly.
9 Troubleshooting
Fault
Possible cause
Remedy
The power tool doesn’t start.
Interruption in the electric supply.
Plug in another electric appliance and
check whether it works.
The supply cord or plug is defective.
Have the parts checked by a trained
electrical specialist and replaced if
necessary.
en
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Printed: 02.04.2014 | Doc-Nr: PUB / 5169271 / 000 / 01