Hilti DD 250 Bedienungsanleitung Seite 45

eye protection, a hard hat, ear protection, protective gloves and safety footwear while the machine
is in use.
Careful handling and use of electric tools
▶ Make sure that the machine is correctly fastened in the drill stand.
▶ Take care to ensure that an end stop is always fitted to the drill stand. The safety-relevant end-stop
function becomes inoperative if this component is not fitted.
▶ Ensure that the accessory tools used have a mounting system that is compatible with the drilling
machine and that they are secured in the chuck correctly.
Electrical safety
▶ Avoid using extension cords with multiple power outlets and the simultaneous use of several
machines connected to one extension cord.
▶ The machine may be operated only when connected to an adequately-rated power supply equipped
with an earth (ground) conductor.
▶ Before beginning work, check the working area (e.g. using a metal detector) to ensure that no
concealed electric cables or gas and water pipes are present. External metal parts of the machine
may become live, for example, when an electric power line is damaged accidentally. This presents a
serious risk of electric shock.
▶ Make sure that the supply cord is not pinched and damaged as the carriage advances.
▶ Never operate the machine without the accompanying PRCD (machines without PRCD: Never
operate the machine without an isolating transformer). Test the PRCD each time before use.
▶ Check the machine's supply cord at regular intervals and have it replaced by a qualified specialist
if found to be damaged. If the machine's supply cord is damaged it must be replaced with
a specially-prepared and approved supply cord available from Hilti Customer Service. Check
extension cords at regular intervals and replace them if found to be damaged. Do not touch the
supply cord or extension cord if it is damaged while working. Disconnect the supply cord plug
from the power outlet. Damaged supply cords or extension cords present a risk of electric shock.
▶ Never operate the machine when it is dirty or wet. Dust (especially dust from conductive materials)
or dampness adhering to the surface of the machine may, under unfavorable conditions, lead to electric
shock. Dirty or dusty machines should thus be checked by Hilti Service at regular intervals, especially if
used frequently for working on conductive materials.
Workplace
▶ Approval must be obtained from the site engineer or architect prior to beginning drilling work.
Drilling work on buildings and other structures may influence the static equilibrium of the structure,
especially when steel reinforcing bars or load-bearing components are cut through.
▶ If the drill stand has not been fastened correctly, always move the machine mounted on the drill
stand all the way down in order to prevent the stand from falling over.
▶ Keep the supply cord, extension cord, water hose and vacuum hose away from rotating parts of
the machine.
▶ Use of the water collection system in conjunction with a wet-type industrial vacuum cleaner is a
mandatory requirement for wet drilling overhead.
▶ Use of the vacuum securing method without an additional means of fastening is prohibited for
drilling in an upward direction.
▶ An additional means of securing the drill stand must be employed when the machine is secured
with the vacuum securing method (accessory) for horizontal drilling.
3 Description
3.1 Parts, indicators and operating controls for diamond core drilling machine DD 250/drill stand
DD­HD 30 1
Diamond core drilling machine DD 250
Multifunction display
@
Button for hole-starting mode
;
Runtime counter button
=
Rating plate
%
On/Off switch
&
Supply cord cover
(
Gear selector
)
Printed: 22.08.2017 | Doc-Nr: PUB / 5245693 / 000 / 02 Printed: 22.08.2017 | Doc-Nr: PUB / 5245693 / 000 / 03
Supply cord with PRCD
+
Water connection
§
Carrying handle (2x)
/
Carbon brush cover (2x)
:
Water flow regulator
∙
Chuck
$
English 37