YASKAWA CIMR-JA Series Installation & Start-Up Manual page 106

4.5 Basic Operation
n Electronic Thermal Motor Protection
The drive has built-in electronic thermal overload protection to detect overload conditions.
This protection meets standards set by UL and cUL for motor thermal overload protection.
The protective feature is activated when the output current rises above the motor rated current
for a specified time. This speed sensitive protective feature interrupts the motor current to
protect the motor wiring and windings in the event of overload, eliminating the need for an
external overload device. When multiple motors are used with a single drive, separate overload
devices are required to properly protect the individual motor branches.
Related Parameters
Parameter
No.
Name
Sets the motor nameplate full load current in
E2-01 Motor Rated amperes (A). This set value becomes the
Current reference value for motor protection, torque
limit, and torque control.
Enables or disables motor thermal overload
Motor
protection (oL1)
Overload
L1-01 0: Disabled
Protection
1: Protection for general purpose motor
Selection
2: Protection for inverter motor
Sets the electronic thermal overload protection
Motor detection time in the motor overload protection
Overload (oL1) function.
L1-02
Protection This setting rarely needs to be changed and
Time should be set in accordance with the overload
tolerance of the motor.
Note: Executing C6-01 (Duty Cycle) changes motor parameters E2 including motor rated current to the values of
the maximum applicable motor.
Setting Procedure
1.
Set E2-01 (Motor Rated Current) to the motor rated current.
Values set for the current become the base current for electronic thermal overload
protection.
2.
Set the proper motor protection level to L1-01.
The ability of the cooling fan to keep an induction motor cool varies by the speed
control range. Protection characteristics of the electronic thermal overload protection
should be set accordingly. Refer to
NOTICE: When connecting multiple motors to one drive, disable the electronic overload
protection of the drive (L1-01 = 0) and protect each motor with its own motor thermal overload.
Failure to comply could result in improper drive operation.
NOTICE: Inadequate motor protection could result in damage to the motor. Configure a motor
thermal overload to disconnect main power to the drive when tripped. When using a thermal relay,
disable the motor protection function (L1-01 = "0").
106 YASKAWA ELECTRIC TOEP C710606 25B YASKAWA AC Drive J1000 Installation & Start-Up Manual
Description
Table 4.7
Setting Range
10 to 200% of drive rated
current
0 to 2
Use L1-13 (Continuous Electrothermal
Operation Selection) to select whether
electronic thermal value is "held" or "not held"
when the power supply is turned off.
When connecting several motors to one drive,
set "0" (disabled) and install a thermal relay on
each motor.
0.1 to 5.0
for motor types and overload tolerances.
Default Setting
Determined by
o2-04 and C6-01
1
1.0 min