Festool C12 EC-TEC Review Manual page 2

load without causing damage.
The C12 monitors the electrical power to the motor
to ensure that the motor operates within safe
parameters. However, make no mistake; the C12
was designed properly in the first place, so it
won't overheat under normal use. The drills
mentioned above were under-engineered so the
manufacturer could claim higher performance
than the drill is realistically capable of
providing.
1
Power Control
Virtually all drills on the
market (including AC and
DC motors) use a similar
design for controlling the
power to the motor. The
trigger switch contains a ll of
the electronic controls.
A small electronic circuit
creates a pulsating signal
for controlling the speed
of the motor, and a
mechanical switch
controls the motor's
direction (refer to How
Variable Speed Controllers
Work on page 5). All of the
power to the motor passes
through this small circuit,
and what's more, passes
through the me chanical
contacts of the
forward/reverse switch.
The C12 uses six high power amplifiers to control
the power to the three phases of the motor. These
are located on the main control board where the
is ample room for a heatsink. The only con
circuit inside the power trigger is a small,
solidstate resistor that is part of the frequency
generator circuit.
Even the forward/reverse control of the C12 is
solidstate. There are no moving parts or contacts
This is not a new concept. U.S. tool manufacturers frequently
1
overstate their claims for marketing purposes. Festool does
not play these marketing games.
to fail. It is a sensor that detects the position of
rare earth magnet located on the push button.
More importantly, the electrical power of the
motor is not flowing through a set of s
contacts like it does with other drills.
Battery Sizes
Whether you're an occasional picture hanger, or a
professional contractor, the C12 is flexible enou
A common misconception with tool batteries is
that they should be fully discharged before
recharging. While there is some truth to this,
re
draining a battery to the point of stalling the moto
trol
can actually cause permanent damage to the
battery. The cells inside the battery pack can
actually change polarity, called cell reversal, under
deep cycling. The C12 monitors the battery to
determine if it is capable of providing the power
required. If the battery cannot supply the powe
With daily use, the batteries can be left in the charger until
2
needed. However, the charger should not be used for long-
term storage of infrequently used batteries.
2
witch
to meet everyone's
needs. The C12 is
available with three
sizes of batteries to
choose from: 1.
NiCd, 2.4 Ah NiCd,
a nd 3.0 Ah NiMH.
The higher the amp-hour (Ah
rating, the longer the battery
will last.
Battery Protection
There are two common w
that battery life gets
shortened; over-charging, and
over-discharging. The C
includes an inte lligent
battery charger to prevent
over charging. The
microprocessor controll
charger rapidly charges
battery, and when full
charge is detected, th
charger switches over to
maintenance mode.
2
a
gh
3 Ah
)
ays
12
ed
the
e
fully
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