Mitsubishi FR-A800

(G) Control parameters
PARAMETERS
625
5
GROUP
G
Overcurrent prevention function (Pr.662)
• The overcurrent prevention function is valid under V/F control and Advanced magnetic flux vector control.
• Increased magnetic excitation rate is lowered automatically when the output current exceeds Pr.662 at the time of
increased magnetic excitation deceleration.
• When the inverter protective function (E.OC[], E.THT) operates due to increased magnetic excitation deceleration, adjust
with Pr.662.
• Overcurrent preventive function will be disabled when Pr.662= "0".
NOTE
• When set to Pr.662 > Pr.22 Stall prevention operation level, overcurrent preventive function will operate at the setting
value of Pr.22. (Operates at Pr.622 when Pr.22 = "0")
Parameters referred to
Pr.22 Stall prevention operation level page 348
Pr.30 Regenerative function selection page 614
Pr.60 Energy saving control selection page 602
Pr.162 Automatic restart after instantaneous power failure selection page 528, page 534
Pr.270 Stop-on contact/load torque high-speed frequency control selection page 478
Pr.261 Power failure stop selection page 540
Pr.350 Stop position command selection page 488
5.16.13 Slip compensation
• Slip compensation will become enabled by calculating the rated motor slip, and setting to Pr.245
Slip compensation is not performed when Pr.245 = "0, 9999".
NOTE
• When the slip compensation is performed, the output frequency may become larger than the set frequency. Set Pr.1
Maximum frequency higher than the set frequency.
• Slip compensation will be disabled in following cases.
At the times of stall preventive (oL, OL) operation, regeneration avoidance operation, auto tuning, encoder feedback control
operation
Parameters referred to
Pr.1 Maximum frequency page 345
Pr.3 Base frequency page 598
Slip of the motor is estimated from the inverter output current at the time of V/F control, and maintain the rotation of the
motor constant.
Pr. Name
Initial
value
Setting
range
Description
245
G203
Rated slip
9999
0.01 to 50% Set the rated motor slip.
0, 9999 Without slip compensation
246
G204
Slip compensation time
constant
0.5s 0.01 to 10s
Set the response time of the slip compensation. Response
will become faster when the value is lowered, but the
regenerative overvoltage (E.OV[]) error will occur more
frequently when the load inertia is larger.
247
G205
Constant-power range
slip compensation
selection
9999
0
Do not perform slip compensation at constant output range
(frequency range higher than the frequency set in Pr.3).
9999 Perform the slip compensation of the constant output range.
Rated slip =
Synchronized speed at the time of base frequency - rated rotation speed
 100[%]
Synchronized speed at the time of base frequency
V/FV/FV/F