Bosch PSB 850-2 RE Manual Original página 24

OBJ_BUCH-875-001.book Page 24 Thursday, June 4, 2009 10:51 AM
24 | English
Mounting the Drill Chuck (see figure J)
The keyless chuck is mounted in reverse order.
Remove the steel pin from the drill hole on
the spindle neck after mounting is complet-
ed.
The drill chuck must be tightened with a
tightening torque of approx. 50–55 Nm.
Operation
Starting Operation
Observe correct mains voltage! The voltage
of the power source must agree with the
voltage specified on the nameplate of the
machine. Power tools marked with 230 V
can also be operated with 220 V.
Reversing the Rotational Direction
(see figure K)
The rotational direction switch 9 is used to re-
verse the rotational direction of the machine.
However, this is not possible with the On/Off
switch 10 actuated.
Right Rotation: For drilling and driving in
screws, push the rotational direction switch 9
left to the stop.
The indicator for right-hand rotation 6 indicates
the selected rotational direction.
Left Rotation: For loosening and unscrewing
screws and nuts, press the rotational direction
switch 9 through to the right stop.
The indicator for left-hand rotation 7 indicates
the selected rotational direction.
Setting the Operating Mode
Drilling and Screwdriving
Set the selector switch 4 to the "Drill-
ing" symbol.
Impact Drilling
Set the selector switch 4 to the "Im-
pact drilling" symbol.
The selector switch 4 engages noticeably and
can also be actuated with the machine running.
2 609 003 378 | (4.6.09)
Gear Selection, Mechanical
The gear selector 11 can be actuated on ma-
chines running at low speed. However, this
should not be done when the machine is
stopped, at full load or running at maximum
speed.
Two speed ranges can be preselected with the
gear selector 11.
Gear I:
Low speed range; for working with
large drilling diameter or for driving
in screws.
Gear II:
High speed range; for working with
small drilling diameter.
If the gear selector 11 cannot be fully engaged,
lightly rotate the drive spindle with the drill bit
by twisting the drill chuck.
Switching On and Off
To start the machine, press the On/Off switch
10 and keep it pressed.
To lock the pressed On/Off switch 10, press the
lock-on button 8.
To switch off the machine, release the On/Off
switch 10 or when it is locked with the lock-on
button 8, briefly press the On/Off switch 10 and
then release it.
Adjusting the Speed/Impact Frequency
The speed/impact rate of the switched on pow-
er tool can be variably adjusted, depending on
how far the On/Off switch 10 is pressed.
Light pressure on the On/Off switch 10 results
in low speed/impact rate. Further pressure on
the switch increases the speed/impact rate.
Preselecting the Speed/Impact Frequency
(PSB 850-2 RE/PSB 850-2 RA)
With the thumbwheel for speed preselection 16,
the required speed/impact frequency can be
preselected even during operation.
The required speed/impact frequency depends
on the material and the working conditions, and
can be determined through practical testing.
Bosch Power Tools