YASKAWA A1000 Technical Manual page 269

Setting 5: Constant torque PM motors (constant torque range of 1:1500)
Sets protection characteristics needed when driving a PM with constant torque. These motors allow for a speed control
from 0.07% to 100% when operating with 100% load. Running the motor below 0.07% speed with 100% load will
trigger an overload fault.
Overload Tolerance
Instantaneous rating (60 s)
150
125
115
100
83
77
67
0 0.07
Percent of base speed (%)
Setting 6: General-purpose motor (50 Hz)
Because the motor (50 Hz) is self-cooled, the overload tolerance drops when the motor speed is lowered. The drive
appropriately adjusts the electrothermal trigger point according to the motor overload characteristics, protecting the
motor from overheat throughout the entire speed range.
Overload Tolerance
150
Rated Speed = 100% Speed
60 s
A: Max. speed for 200LJ and above
B: Max. speed for 160MJ to 180 LJ
C: Max. speed for 132MJ and below
100
90
Continuous
50
A
B
05 33 100 120 167 200
Speed (%)

L1-02: Motor Overload Protection Time
This setting rarely requires adjustment. Sets the time it takes the drive to detect motor overheat due to overload. If the
motor overload tolerance protection time when an overload of 150% is imposed after continuous operation at 100% is
clear, set that time as the value.
No.
L1-02
Defaulted to operate with an allowance of 150% overload operation for one minute in a hot start; after continuous
operation at 100%.
• Figure 5.90 shows an example of the electrothermal protection operation time using a general-purpose motor
operating at 50 Hz with L1-02 set to one minute.
Motor overload protection operates in the area between a cold start and a hot start.
• Cold start: Characteristics of motor protection operation time in response to an overload situation that was suddenly
reached when starting a stationary motor.
• Hot start: Characteristics of motor protection operation time in response to an overload situation that occurred while
the motor was operating continuously at or below its rated current.
YASKAWA ELECTRIC SIEP C710616 27G YASKAWA AC Drive A1000 Technical Manual
100 120 130 150
C
Name
Motor Overload Protection Time
Cooling Ability
Motor is designed to effectively cool itself at
ultra-low speeds (about 0.07% of base speed).
Cooling Ability
Motor designed to operate from line power.
Motor cooling is most effective when running at
rated base frequency (check the motor nameplate or
specifications).
5.8 L: Protection Functions
Overload Characteristics
Continuous operation with 100% load from 0.07% to
100% of base speed.
Overload Characteristics
Continuous operation at less than line power
frequency with 100% load can trigger motor
overload protection (oL1). A fault is output and the
motor will coast to stop.
Setting Range
0.1 to 5.0 minutes 1.0 minutes
Default
5
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