Filter
Top Products
PROTECTIVE FUNCTIONS
133
(3) Warnings
FR-PU04 Indication
OL
Name
Stall prevention (overcurrent)
During
acceleration
If a current of more than 150%
(
Note 4
)
of the
rated inverter current flows in the motor, this
function stops the increase in frequenc
y
until the
overload current reduces to prevent the inverter
from resultin
g
in overcurrent shut-off. When the
overload current has reduced below 150%, this
function increases the frequency again.
During
constant-speed
operation
If a current of more than 150%
(
Note 4
)
of the
rated inverter current flows in the motor, this
function lowers the frequenc
y
until the overload
current reduces to prevent overcurrent shut-off.
When the overload current has reduced below
150%, this function increases the frequenc
y
up to
the set value.
Description
During
deceleration
If a current of more than 150%
(
Note 4
)
of the
rated inverter current flows in the motor, this
function stops the decrease in frequenc
y
until the
overload current reduces to prevent the inverter
from resultin
g
in overcurrent shut-off. When the
overload current has reduced below 150%, this
function decreases the frequency again.
Check point
Check the motor for use under overload.
Corrective action
The acceleration/deceleration time may change.
Increase the stall prevention operation level with Pr. 22 "stall
prevention operation level", or disable stall prevention with Pr. 156
"stall prevention operation selection".
Note:4 The stall prevention operation current can be set as desired. It is factory-set to
150%.
FR-PU04 Indication
oL
Name
Stall prevention (overvoltage)
Description
During
deceleration
If the re
g
enerative ener
gy
of the motor increases
too much to exceed the brake capabilit
y
, this
function stops the decrease in frequenc
y
to
prevent overvolta
g
e shut-off. As soon as the
re
g
enerative ener
gy
has reduced, deceleration
resumes.
Check point
Check for sudden speed reduction.
Corrective action
The deceleration time ma
y
chan
g
e. Increase the deceleration time
using Pr. 8 "deceleration time".
FR-PU04 Indication
PS
Name
PU stop
Description
A stop made by pressing the
STOP
RESET
key of the PU has been set in
Pr. 75 "PU stop selection".
Check point
Check for a stop made by pressing the
STOP
RESET
key of the PU during
DeviceNet operation.
Corrective action
Refer to page 88.