YASKAWA CR700, Technical Manual, Page: 748 / 886

11.9 L: Protection Function
748 YASKAWA SIEPC71061723A YASKAWA AC Drive CR700 Technical Manual
Load Tolerance Cooling Capability Overload Characteristics (at 100% motor load)
This motor is designed to operate with commercial line
power. Operate at a 50 Hz base frequency to maximize
the motor cooling ability.
If the motor operates at frequencies less than commercial
line power, the drive will detect
oL1
. The drive triggers a
fault relay output and the motor coasts to stop.
■
L1-02: Motor Overload Protection Time
No.
(Hex.)
Name Description
Default
(Range)
L1-02
(0481)
Motor Overload Protection
Time
Sets the operation time for the electronic thermal protector of the drive to prevent damage to the
motor. Usually it is not necessary to change this setting.
1.0 min
(0.1 - 5.0 min)
Set the overload tolerance time to the length of time that the motor can operate at 150% load from continuous
operation at 100% load.
When the motor operates at 150% load continuously for 1 minute after continuous operation at 100% load (hot
start), the default setting triggers the electronic thermal protector.
Figure 11.88 shows an example of the electronic thermal protector operation time. Motor overload protection
operates in the range between a cold start and a hot start.
This example shows a general-purpose motor operating at the base frequency with
L1-02
set to 1.0 min.
• Cold start
Shows the motor protection operation time characteristics when the overload occurs immediately after starting
operation from a complete stop.
• Hot start
Shows the motor protection operation time characteristics when overload occurs from continuous operation
below the motor rated current.
Figure 11.88 Protection Operation Time for a General-purpose Motor at Rated Output Frequency
■
L1-03: Motor Thermistor oH Alarm Select
No.
(Hex.)
Name Description
Default
(Range)
L1-03
(0482)
Motor Thermistor oH
Alarm Select
Sets the drive operation when the PTC input signal to the drive is at the oH3 [Motor Overheat
(PTC Input)] detection level.
3
(0 - 3)
0 : Ramp to Stop
The drive ramps the motor to stop according to the deceleration time. Fault relay output terminal MA-MC will
turn ON, and MB-MC will turn OFF.
V/f CL-V/f OLV CLV AOLV
V/f CL-V/f OLV CLV AOLV