Current Limitation Functions - Omron 3G3RX Quick Start Manual

PROGRAMMING RX
In standard operation, inverter uses a reference source selected by A001 for the output frequency which may be a fixed or vari-
able value. To enable PID operation is necessary to set A071 to "01" and this will cause the inverter to calculate the target fre-
quency or set point. This presents some advantages like potential energy saving and direct control over the process variable
instead of the motor speed.
Parameter
A071
A072
A073
A074
A075
A076
A077
A078
A079 PID feed forward selection
C044 PID deviation excessive level
C052
C053

3.21 Current limitation functions

Overload Restriction reduce the output frequency while motoring or increase
it during regeneration to restrict the overload when the output current exceeds
a certain limit. You can adjust the inverter to apply overload restriction only
during constant speed allowing higher currents for acceleration.
Additionally two separate sets of parameters are available and is possible to
choose between them by intelligent input terminal "39: OLR"
Over-current Trip Suppression function monitors the motor current
and actively changes the output frequency profile to keep the motor cur-
rent below 150% of the motor rated current. Basically the acceleration
ramp is stopped above this current and only restarts when the current
goes below the set value. It avoids the trip but the total acceleration time
could be longer when this function is enable.
Please consider that this function doesn't operate keeping a constant
motor current so is still possible to have an over-current trip during
extreme acceleration.
RX Quick Start Guide
Parameter name
PID selection
PID P gain
PID I gain
PID D gain
PID scale
PID feedback selection
Reverse PID function
PID output limit function
PID FB upper limit
PID FB lower limit
Description
00: OFF (Disabled)
01: ON (+) (Enabled)
02: ON (+/-) (Reverse output enabled)
0.2 to 5.0
0.0 to 3600.0 s
0.00 to 100.00 s
0.01 to 99.99
00: OI
01: O
02: Modbus (RS485 communication)
03: Pulse (Pulse train frequency)
10: Math (Operation function output)
00: OFF (Deviation = Target value - Feedback value)
01: ON (Deviation = Feedback value - Target value)
0.0 to 100.0%
00: Disabled
01: O
02: OI
03: O2
0.0 to 100.0%
0.0 to 100.0%
0.0 to 100.0%
Motor
current
B022
0
Output
frequency
Powering
0
B027 01
OC LAD STOP = Enabled
=
Motor
Approx. 150% of the inverter
current
rated current
0
Output
frequency
0
Set acc time
Restriction area
t
Regenerating
B023
t
B023
t
Stops accel
Resumes accel
t
Actual acc time
33