AB Quality ALLEN-BRADLEY 1391-DES, User Manual

Page: 54 / 149

Chapter 6
Programming
6-17
Parameter 156 – Positive Current Limit (Pos. Cur Limit)
Parameter 156 specifies the maximum allowable positive motor current
that can be commanded. If greater than parameter 48, parameter 48 will
then set the limits.
Parameter Type: View/modify in Modify level and Maintenance level
Minimum Value: 10% rated motor current
Maximum Value: 300% rated motor current or 2 times drive rating (whichever is less)
Default Value: Set by “Setup drive with motor data” routine
Parameter 157 – Negative Current Limit (Neg. Cur Limit)
The maximum allowable negative motor current that can be commanded is
specified through this parameter. If greater than parameter 48, parameter 48
will then set the limits.
Parameter Type: View/modify in Modify level and Maintenance level
Minimum Value: 10% rated motor current
Maximum Value: 300% rated motor current or 2 times drive rating (whichever is less)
Default Value: Set by “Setup drive with motor data” routine
Parameter 158 – Current Rate Limit (Cur Rate Limit) *
The largest change in the current reference per velocity loop sample that
will be allowed is specified through this parameter. Value shown on the
display is in amperes/second. Description is based on percentage of motor
rating to allow interpretation of value.
Parameter Type: View/modify in Maintenance level
Minimum Value: 130% rated motor current per second
Maximum Value: 80% rated motor current per millisecond
Default Value: 36% of motor rated current/ms, but will change according to motor selection
Parameter 159 – Current Preload (Cur Preload)
This parameter specifies the amount of preload added to the velocity loop
Pl output.
Parameter Type: View/modify in Modify level and Maintenance level
Minimum Value: –200% rated motor current
Maximum Value: +200% rated motor current
Default Value: 0
Parameter 168 – KP Velocity Loop (Prop Gain kp)
This parameter controls the proportional error gain of the velocity
regulator. For example, if KP = 8, then velocity (1000 rpm) error will
produce a (rated motor) current torque reference.
Parameter Type: View/modify in Modify level and Maintenance level
Minimum Value: 0
Maximum Value: 560
Default Value: 100