Rockwell Automation 20D PowerFlex 700S Drive Ph I Control, Frames 1...11 - Manual (Page 214)

C-4 Application Notes
Figure C.1 Motor Overload Curve With Parameter 338 [Mtr I2T Spd Min] Is Less Than
1.0
Figure C.2 Motor Overload Curve With Parameter 338 [Mtr I2T Spd Min] Is Equal To
1.0
Overspeed Limit The absolute overspeed limit parameter, parameter 335 [Abs OverSpd Lim],
is an adjustable setting. This sets a limit tolerance below parameter 30 [Rev
Speed Lim] and above parameter 31 [Fwd Speed Lim], that is allowable.
This can be used as a safe working speed limit.
Example 1 Speed reference is set to equal parameter 31 [Fwd Speed Lim].
Based on tuning of the drive, the speed could overshoot the
commanded speed. If parameter 335 [Abs OverSpd Lim] is set
equal to the forward speed limit and an overshoot is speed
occurs, the drive will fault on an absolute overspeed.
Example 2 Drive is configured as a torque follower. If the mechanical
connection to the load is severed, the torque command to the
drive will probably be greater than the motor unloaded will
require to maintain the system speed. This will cause the motor
speed to increase until the torque command is met. Setting
parameter 335 [Abs OverSpd Lim] to the safe motor speed will
cause the fault to occur when the motor speed increase beyond
this limit.
P336 [Service Factor]
Current
P337 [Mtr I2T Curr Min]
Speed
P338 [Mtr I2T Spd Min] Base Speed (1.0)
When motor current exceeds the value of the curve, Mtr
OL Output integrates. A motor overload exception event
occurs when the value in Mtr OL Output reaches 1.0.
The value of Mtr OL Output is visible in parameter 330
[Fault TP Data] when the value of parameter 329 [Fault
TP Sel] equals 13.
P336 [Service Factor]
Current
Speed
When the value of parameter 338 [Mtr I2T Spd Min] equals
1.0, the curve is flat - at the value of rated motor current
times the value of parameter 336 [Service Factor]. If motor
current exceeds the value of the curve, the value of Mtr OL
Output integrates. The value of Mtr OL Output is visible in
parameter 330 [Fault TP Data] when the value of
parameter 329 [Fault TP Sel] equals 13.