Operation; Working Advice - Bosch Professional GWS 900-125 S Original Instructions Manual

12 | English

Operation

Start-Up
Pay attention to the mains voltage! The voltage of the
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power source must match the voltage specified on the
rating plate of the power tool. Power tools marked
with 230 V can also be operated with 220 V.
When operating the power tool using a mobile generator that
does not have sufficient reserve capacity or an adequate
voltage control system with inrush current boost converter,
loss of performance or atypical behaviour may occur upon
switch-on.
Please check the suitability of the power generator you are
using, particularly with regard to the mains voltage and fre-
quency.
Switching on/off
To start the power tool, push the On/Off switch (2) for-
wards.
To lock the On/Off switch (2), press the On/Off switch (2)
down at the front until it latches.
To switch off the power tool, release the On/Off switch (2)
or, if it is locked, briefly push down the back of the On/Off
switch (2) and then release it.
Speed preselection
(GWS 900-125 S)
You can select the required speed using the speed preselec-
tion thumbwheel (3), even during operation. The informa-
tion in the table below describes the recommended values.
Material Application
Metal Removing paint
Metal Brushing, removing rust
Metal, stone Grinding
Metal Rough grinding
Metal Cutting
The values specified for speed levels are guide values.
The rated speed of the accessory must be at least
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equal to the maximum speed marked on the power
tool. Accessories running faster than their rated speed
can break and fly apart.

Working Advice

Pull the plug out of the socket before carrying out any
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work on the power tool.
Exercise caution when cutting slots in structural walls;
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see the "Information on structural design" section.
Clamp the workpiece if it is not secure under its own
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weight.
Do not load the power tool so heavily that it comes to a
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stop.
1 609 92A 8YF | (01.08.2023)
Always check abrasive tools before using them. The
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abrasive tool must be fitted properly and be able to
move freely. Carry out a test run for at least one
minute with no load. Do not use abrasive tools that are
damaged, run untrue or vibrate during use. Damaged
abrasive tools can burst apart and cause injuries.
Restart protection
(GWS 900-125 S)
The restart protection feature prevents the power tool from
uncontrolled starting after the power supply to it has been
interrupted.
To restart the tool, set the on/off switch (2) to the "off" posi-
tion and then switch the power tool on again.
Soft start
(GWS 900-125 S)
The electronic soft start limits the torque when the power
tool is switched on and enables a smooth start-up.
Note: If the power tool runs at full speed immediately after
being switched on, this means that the soft start and restart
protection mechanisms have failed. The power tool must be
sent to the after-sales service immediately (see the "After-
Sales Service and Application Service" section for ad-
dresses).
Application tool
Abrasive disc
Cup brush, abrasive disc
Grinding disc
Grinding disc
Cutting disc
If the power tool has been subjected to a heavy load,
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continue to run it at no-load for several minutes to
cool down the accessory.
Do not use the power tool with a cut-off stand.
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Do not touch grinding and cutting discs until they have
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cooled down. The discs can become very hot while work-
ing.
Rough grinding
Never use cutting discs for rough grinding.
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The best rough grinding results are achieved with a set angle
of 30° to 40°. Move the power tool back and forth with mod-
erate pressure. This will ensure that the workpiece does not
become too hot or discolour and that grooves are not
formed.
Thumbwheel position
2–3
3
4–6
6
6
Bosch Power Tools