Hilti DD 120 Operating Instructions Manual page 37

7.4 Drilling with use of the water collection system
(accessory)
WARNING
Water must not be allowed to run over the motor and
cover.
CAUTION
The water is drained through a hose. Overhead drilling
is not permissible.
1. Slowly open the water flow regulator until the desired
volume of water is flowing.
2. Press the on/off switch on the machine (position "I").
The drilling performance indicator lights orange.
3. Release the carriage brake.
4. Turn the handwheel until the diamond core bit is in
contact with the base material.
5. Apply only light pressure until the diamond core bit
has centered itself and then increase the pressure.
6. Regulate the contact pressure while observing the
drilling performance indicator.
NOTE The drilling performance indicator lights or-
ange after switching on. Optimum drilling perform-
ance is achieved when the drilling performance in-
dicator shows a green light. If the drilling perform-
ance indicator shows a red light, reduce the pressure
applied to the core bit.
7.5 Drilling with use of the water collection system
and wet-type industrial vacuum cleaner
(accessories) 8
WARNING
Water must not be allowed to run over the motor and
cover.
WARNING
The diamond core bit fills with water during overhead
drilling. Drilling upwards at an angle is not permissible
(the water collector cannot function correctly).
NOTE
The vacuum cleaner must be switched on manually be-
fore drilling is started and switched off manually once
drilling is completed.
1. Switch the vacuum cleaner on. Do not use the
vacuum cleaner in automatic mode.
2. Connect the water supply.
3. Open the water flow regulator.
4. Press the on/off switch on the machine (position "I").
The drilling performance indicator lights orange.
5. Release the carriage brake.
6. Turn the handwheel until the diamond core bit is in
contact with the base material.
en
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