
B-65232EN/03 FANUC AC SERVO MOTOR β series 2.SPECIFICATIONS AND CHARACTERISTICS
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2.2 CHARACTERISTIC CURVE AND DATA SHEET
See Section 4.2 of Part I of this manual for details of each item.
(1) Speed - torque characteristics
Typical characteristics of speed and output torque are indicated.
The data curve shown in this specification is for the rated input
voltage (200V). Note, however, that the intermittent operating
zone varies with the input voltage of the driving unit.
(2) Overload duty characteristic
The overload duty characteristic curves are determined based on
the temperature restriction for the single motor unit (such as
protection based on a thermal protector). The curves are
determined by assuming that the temperature increases gradually
under certain overload conditions. Therefore, the curves do not
apply to the rapid temperature rise which occurs, for example,
when an overcurrent flows in the motor windings until the
thermal trip operates.
A thermal software function is provided to prevent an abrupt
temperature rise in the motor by monitoring for abnormal current
in the motor. This function may put a thermal limit to the
operation of the motor when it is frequently accelerated and
decelerated.
Driving units (such as amplifiers) contain their own overheating
protection devices. Therefore, note that the operation of motor
may be limited according to thermal limit of driver.
(3) Data sheet
The parameters given in the data sheet are representative values
for an ambient temperature of 20°C. They are subject to an error
of ±10%.
The indicated logical values are threshold values for the single
motor unit (when the motor is not restricted by the control
system).
The maximum torque that can be produced during acceleration
or deceleration is temporarily calculated as the approximate
product of the motor torque constant and the current limit value
of the amplifier.
Example : βM0.5/4000
Motor torque constant = 0.22(Nm/Arms)
Amplifier limit value = 20Apeak
Maximum torque value = 20 × 0.707 × 0.22 = 3.1(Nm)
↑ (Converted to an effective value)
However, this value is a theoretical value. So, the actual
maximum torque depends on the motor, amplifier, servo
software, and power supply used. Particularly when a maximum
current flows through the motor, the actual maximum torque can
be far less than a calculated value due to an influence such as
magnetic saturation.
The data curve of speed-torque characteristics indicates typical
data obtained by combining a motor with an amplifier actually. It
is requested to make a study based on the data curve.