Hilti DD 120 Operating Instructions Manual page 36

7.1.1 Unlocking the machine
1. Connect the supply cord to the electric supply and
press the "I" or "Reset" button on the ground fault
circuit interrupter. The yellow theft protection indic-
ator LED blinks. The machine is now ready to receive
the signal from the TPS key.
2. Hold the TPS key or the TPS watch strap buckle
against the lock symbol. The machine is unlocked
en
as soon as the yellow theft protection indicator LED
no longer lights.
NOTE If, for example, the electric supply is briefly
interrupted due to a power failure or disconnected
when moving to a different workplace, the machine
remains ready for operation for approx. 20 minutes.
In the event of a longer interruption, the TPS key
must be used again to unlock the machine.
7.1.2 Activation of the theft protection system for
the machine
NOTE
Further detailed information on activation and use of the
theft protection system can be found in the operating
instructions for the theft protection system.
7.2 Switching on and checking the ground fault
circuit interrupter (PRCD)
208188 B/2.2004
(Note: An isolating transformer is used with the GB ver-
sion.)
1. Plug the machine's supply cord into an earthed
power outlet.
2. Press the "I" or "Reset" button on the ground fault
circuit interrupter (PRCD).
The drilling performance indicator lights orange.
3. Press the "0" or "Test" button on the ground fault
circuit interrupter (PRCD).
The indicator must go out.
32
WARNING If the indicator continues to light, fur-
4.
ther operation of the machine is not permissible.
Have the machine repaired by a qualified specialist
using genuine Hilti spare parts.
Press the "I" or "Reset" button on the ground fault
circuit interrupter (PRCD).
The indicator must light.
7.3 Drilling without use of the water collection
system and industrial vacuum cleaner
WARNING
Water must not be allowed to run over the motor and
cover.
WARNING
Water drainage is uncontrolled. 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.