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5.2 Fitting the drill steel
Use only TE-MDR drill steels with the appropriate
TE-MCE connection end.
1. Clean away any dirt adhering to the connection end
and apply a little grease to it.
2. Screw the drill steel fully into the connection end.
3. Guide the connection end into the chuck. Rotate the
drill rod until the splines and grooves are in alignment
and then push it into the chuck as far as it will go.
4. Close the chuck locking mechanism and check that
the connection end is held securely.
5.3 Fitting the water leg
Use only the TE-MW and TE-MW T water leg intended
for use with this tool, thus ensuring correct functionali-
ty of the water supply to the machine.
1. Clean the connecting pin on the water leg, removing
any dirt adhering to it.
2. Position the guide on the underside of the front hous-
ing of the tool on the water leg and insert the con-
necting pin in the hole provided.
3. Secure the connection by inserting the retaining pin
in the hole in the connecting pin.
5.4 Water connection
The tool and drill bit are water-cooled and the water has
a flushing function during drilling.
– Water pressure: min. 3 bar, max. 5 bar
– Water temperature: approx. 10–20°C
– Cooling water flow rate: approx. 10 l/min
– Permissible degree of water pollution: <40 µm.
The cooling water is supplied to the tool through a stud
on the water leg saddle which is connected to the water
supply.
When the Hilti TE-MW or TE-MW T water leg is used,
water connection is by way of a 1
″
conus connector.
Check the flow of water. Water must spray out of the
bores in the drill bit.
5.5 Electrical connection
The tool must be powered by an alternating current sup-
ply that complies with the information given on the type
plate.
The tool must be connected to an adequately dimen-
sioned earth conductor by way of the mains plug. The
earth connection must be checked at regular intervals to
ensure correct functionality.
The electric supply must be equipped with a pulse-con-
trolled / DC-sensitive ground fault circuit breaker (type
A or B as per IEC 61008) with a sensitivity of max. 30
mA. This device must be checked at regular intervals in
accordance with the manufacturer’s instructions.
If operated in atmospheres where there is a risk of
explosion
Only approved plug/socket systems (EEx d I/IIA, IP66)
in accordance with 94/9/EC may be used, e.g. Hilti
TE-MPH with 24 V pilot contact, monitored earth/ground,
220–240 V phase, neutral conductor. Disconnection
from the power supply must be by way of an isolating
switch.
The plug
햽
features a pilot contact for the purpose of
external monitoring of the earth/ground connection (pilot
contact switching). In addition, the tool is equipped with
a diode (6 A) between the pilot contact and the earth/ground
conductor.
The monitoring circuit must be self-testing (intrinsical-
ly safe) in accordance with EN/IEC 60079-11.
5.6 Use of extension cords
Use only extension cords of a type approved for the applic-
able application (TE-MEC) and with conductors of ade-
quate cross-section to avoid a drop in the tool’s perfor-
mance and overheating of the supply cord.
The recommended conductor cross-section is 2.5 mm
2
over a length of max. 60 m.
Check that the extension cord and plug are adequately
protected by a suitably-rated fuse in the electric supply.
To avoid overheating, always unroll the full length of the
extension cord from the drum even when only a short
length is required.
Connect the tool to the electric supply only once it has
been set up ready for use.
5.7 Use of a generator or transformer
When the tool is powered by a generator or transformer,
the following conditions must be fulfilled:
●
AC voltage, output power at least 7000 VA.
●
The operating voltage must be 5% and –10%
of the rated voltage at all times.
●
Frequency range 50–60 Hz.
●
Automatic voltage regulation with starting boost.
●
The unit must be correctly earthed.
●
A ground fault circuit breaker as described at section
5.5 must be used.
Never operate other machines or appliances from the
generator or transformer at the same time. Switching
other machines or appliances on and off may cause
undervoltage and / or overvoltage peaks, resulting in
damage to the tool.
-CAUTION-
■
The drill bit may become hot during use.
■
There is a risk of burning the hands.
■
Wear protective gloves when changing
drill bits.
Printed: 20.04.2017 | Doc-Nr: PUB / 5136192 / 000 / 00
Printed: 20.04.2017 | Doc-Nr: PUB / 5136192 / 000 / 01