6
Overload Protection
To protect the user, motor and drill bit, the DB 1700 N is equipped with a mechanical, electrical and thermal
overload protection.
Mechanical:
In case of sudden jamming of the drill bit, the drilling spindle is unclutched from the motor by
means of a slip clutch.
Electrical:
To warn the user against overstressing the tool by applying to high an advance force, the handle
includes a LED. It does not light during idle run or at normal load. At overload, it lights red. In that
case the tool most be stress-relieved. In case of longer non-observation of the rad indication, the
electronics will independently switch the tool off. After relieving is switching the tool off and on, the
work can be continued as normal.
Thermal:
In case of permanent overload, a thermocouple protects the motor against destruction. In that case,
the tool switches off and can only be restarted after a certain cooling-down period (approx. 2
minutes). The cooling-down time depends on the temperature of the motor winding and ambient
temperature.
Safety Clutch
The slip clutch served for compensation of shocks and overload.
To keep its functionability, it should not slip for more than 2 seconds. In case of excessive wearing, it can be
replaced by an authorized service centre.
Drill Bits
Use only appropriate drill bits for the material to be drilled in. You can protect your tool by using only well balanced
drill bits without deformation.
Make sure that the diamond segments have sufficient cutting clearance towards the bit body.
Changing Drill Bits
Attention!
When you use or sharpen the machine, it might heat up enormously. You could burn your hands or get cut
or ripped by the segments. Therefore, always use protective gloves when changing the drill bit.
The drilling spindle has a right-hand thread.
To ease screwing on and off, always use a SW 32 open-end wrench at the drilling spindle.
Never use a hammer, because this may damage both the drill bit and the tool.
Some water-resistant grease on the drilling spindle threat or a copper ring between spindle and drill bit will
simplify removal of the drill bit.
Attention!
The bits may have got hot due to use or sharpening. There is a danger of burning ones hands or injuring oneself at
the segments’ edges.
When changing the drill bits, you should always wear protective gloves.
