5
-58
L: Protection Function Constants
The following settings are made with the protection function constants (L constants): Motor selection func-
tion, power loss ridethrough function, stall prevention function, frequency detection, torque limits, and hard-
ware protection.
Motor Overload: L1
User constants for motor overloads are shown in the following table.
Con-
stant
Number
Name
Description
Setting
Range
Factory
Setting
Change
during
Opera-
tion
Control Methods
MEMO-
BUS
Regis-
ter
Page
Display
V/f
V/f
with
PG
Open
Loop
Vec-
tor
1
Flux
Vec-
tor
Open
Loop
Vec-
tor
2
L1-01
Motor pro-
tection
selection
Sets whether the motor over-
load function is enabled or dis-
abled at electric thermal
overload relay.
0: Disabled
1: General-purpose motor
protection
2: Inverter motor protection
3: Vector motor protection
In some applications when the
Inverter power supply is
turned off, the thermal value is
reset, so even if this constant is
set to 1, protection may not be
effective.
When several motors are con-
nected to one Inverter, set to 0
and ensure that each motor is
installed with a protection
device.
0 to 3
1
No
Q
Q
Q
Q
Q
480H
4-5
6-57
MOL Fault
Select
L1-02
Motor pro-
tection time
constant
Sets the electric thermal detec-
tion time in seconds units.
Usually setting is not necessary.
The factory setting is 150%
overload for one minute.
When the motor's overload
resistance is known, also set the
overload resistance protection
time for when the motor is hot
started.
0.1 to
5.0
1.0 min
No
A
A
A
A
A
481H
6-57
MOL Time
Const
L1-03
Alarm oper-
ation selec-
tion during
motor over-
heating
Set H3-09 to E and select the
operation when the input motor
temperature (thermistor) input
exceeds the alarm detection
level (1.17 V).
0: Decelerate to stop using the
deceleration time in C1-02.
1: Coast to stop
2: Emergency stop using the
deceleration time in C1-09.
3: Continue operation (H3 on
the Operator flashes).
0 to 3
3
No
A
A
A
A
A
482H
6-60
MOL Thm
Input
