YASKAWA HV600, Technical Reference

Page: 318 / 794

5.8 L: Protection Functions
318 YASKAWA SIEPYAIH6B01A HV600 AC Drive Bypass Technical Reference
Figure 5.69 Protection Circuit Configuration to Connect More than One Motor to One Drive
NOTICE: When you connect more than one motor to one drive or when the motor amp rating is higher than the drive amp rating, set
L1-01 =0 [Motor Overload (oL1) Protection = Disabled] and install thermal overload relays for each motor. The electronic thermal
protection of the drive will not function and it can cause damage to the motor.
1 : Variable Torque
Use this setting for general-purpose motors with a 60 Hz base frequency.
The overload tolerance decreases as motor speed decreases because the cooling fan speed decreases and the ability of
the motor to cool decreases in the low speed range.
The overload tolerance characteristics of the motor change the trigger point for the electronic thermal protector. This
provides motor overheat protection from low speed to high speed across the full speed range.
Load Tolerance Cooling Capability
Overload Characteristics
(at 100% motor load)
This motor is designed to operate with commercial line
power. Operate at a 60 Hz base frequency to maximize the
motor cooling ability. If the motor operates at frequencies less than 60 Hz, 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 5.70 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