Berner 367866, Safety And Users Manual, Page: 28 / 88

English 10
07-2020
▪ this drilling technique is safer and more effective
than the hand-held drilling technique;
▪ this technique is suitable when you want to make
holes with diameter below the maximum drilling
diameter reported on your product, into any kind of
material. In particular you must use a drill stand if
you are drilling outside the limits defined before for
hand-held drilling, in terms of material and
diameter.
when you use your core drill mounted to a
stand, follow the directions given by the stand
manufacturer;
Power supply
Earth (Ground)
▪ the metallic parts of your core drill are connected to
the earth.
▪ make sure that the socket and possible extension
cords and multiple sockets have the earth
connection and that your electrical system is
properly connected to the earth.
Warning: for your safety, it is important that
the whole system (electrical system, extension
cords, sockets etc.) is connected to the earth.
If you are not sure, ask a qualified electrician
for a check.
Extension cords
▪ when you have to operate with your core drill far
from an electrical socket, you can use an extension
cord. If you use it make sure that the section of the
cord is suitable and that the cord is provided with
ground conductor;
▪
the extension cord (made up of cable, plug and
socket) must be suitable for outdoor use. It is better
if the cord is made of rubber and it is H07RN-F;
▪ follow the chart shown in figure 11 on this manual
for the choice of the right section of the conductors;
▪ if you use more than one extension cord make sure
that every cable in each extension cord has a
section not lower than the value shown on the chart
in figure 11, considering the total length of the
extension cords;
▪
remember that the more an extension cord is long
the more the voltage drop is high and the worse is
the operation of your cor
e drill. Don’t use extension
cords if you have to operate too far from the
electrical socket.
PRCD: portable residual current device
(GFI)
▪ your core drill is equipped with a safety portable
residual current device (PRCD) assembled on the
cord. This device is shown in figure 8;
▪
never use core drill without PRCD;
▪ before starting to drill make sure the PRCD works
properly. In order to do so, plug the core drill in and
press the button Reset (O): the indicator appears
(P) showing that electricity is available to the core
drill. Then press the button Test (N) that tests if the
device works properly. When you press it the circuit
breaker inside the PRCD should cut the power off
leading the switch automatically to go to the off
position and the indicator disappears;
▪
if, when drilling, the PRCD cuts the power: stop
working, set the main switch of you core drill on the
OFF position and bring your core drill to an
authorized service centre in order to remove the
causes of the electrical dissipation.
Preliminary operations
In order to prepare your core drill to operate, follow these
steps. Before proceeding with the preparation make sure
that the plug is disconnected from the outlet.
a) If you use your core drill manually, fix the auxiliary
handle (B) to the core drill, as shown in figures 1 and
2.
Warning:
If you don’t use the auxiliary
handle you can lose control of the core drill
and this can lead to serious personal
injuries.
If you use your core drill with a stand, fix the machine
into the collar of the stand as shown in figure 16.
Follow instructions given by the stand
manufacturer to fix the stand to the
material you want to drill.
b) Follow these instructions:
▪ if you want to operate in wet mode, connect the
hosepipe to the core drill as explained in the
following Water insertion paragraph. Make sure that
the water valve is shut.
▪ if your core drill is equipped with a gear change
(figure 2 A), see the data plate on your core drill as
shown in figure 12. Identify the right rotating speed
according to the diameter of the core bit you are
using and the material you are drilling. The symbol
refers to abrasive materials (like tiles, gasbeton,
poroton…), the
symbol refers to hard materials
(like reinforced concrete…).
Select the required
gear change position just when the motor is at
standstill;
▪ refer to the following paragraph Diamond core bit
mounting and replacement in order to mount the
core bit to your core drill.
ON/OFF switch
Warning : for your safety, you must get
familiar with the functioning of the switch in
order to prevent unintentional switch-on and
to switch-off the machine quickly, if necessary.
▪
The ON/OFF switch is shown in figure 4 (E);
▪
see figure 9 in order to understand how to use the
switch;
▪ the switch is equipped with a feature ( lock-off ) that
prevent unintentional switch-on of the core drill.
▪
the switch is equipped with a feature ( lock-on ) that
locks the switch in the on position;
Warning : the lock-on feature must be used
ONLY when the machine is fixed on a drill
stand. You must not use the lock-on
feature when you are using your core drill
hand-held.
Connection to a water supply
Wet drilling needs the insertion of water into the core drill.
This can be done in two ways: by using the water insertion
system shown in figure 2 or by using the combined system
shown in figure 3. During wet drilling follow these
instructions:
▪ use just the water insertion systems provided with
your machine, depicted in figure 1, 2 or 3. The
water systems include a valve (C) and a quick hose
connector (D);
▪ the maximum pressure allowed of the incoming
water is 4 bar;