a2b Obree, Руководство пользователя

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37
Whenever a motor is operated beyond
the optimum operating point, its efficiency
decreases. This results in the energy not
being optimally converted any longer, but
a part of the supplied energy is converted
into heat. In this way, the range decreases
and the heat must be discharged. In the
neodrives motors this heat is discharged
through a large contact surface inside the
motor (stator carrier) to the dropout or
chainstays of the bicycle frame. Cooling
ribs inside and outside the drive casing
additionally ensure the greatest possible
heat exchange with the surroundings. Heat
which cannot be discharged results in the
drive motor being heated up.
The neodrives wheel hub motors monitor
both the supplied energy and the
temperatures in the motor. In this way,
any damage for overheating by reason of
overload can be avoided. This, however,
results in the motor performance available
to the rider being reduced to avoid
overheating.
If the temperature of 80°C is exceeded in
the motor electronics, the motor control
reduces the supplied power and thus the
assistance. This is indicated in the sMMI by
the thermometer symbol shown opposite
(see section 3.2.11). As the temperature
increases, the power is continually reduced.
This means: the higher the
temperature increase in the
motor, the less drive power can
be obtained and the less assistance is
available. When the motor cools down, the
supplied energy is increased again and the
drive power increases.
This control of drive power depending on
the motor temperature is infinitely variable
so that there is always asistance available,
but the motor cannot be damaged by
overheating.
In practice
The above aspects, in practice, lead to a
dependence on the outside temperature,
the total weight, incline, terrain, cadence,
air pressure and speed. These factors may
lead to a temperature which causes the
power or assistance to be reduced. This,
however, does not mean a fault or failure
of the drive, you may proceed with less
assistance. In extreme cases, a short-term
complete shut off may occur.