Rockwell Automation 20G PowerFlex 750-Series AC Drives - Manual (Page 168)

168 Rockwell Automation Publication 750-RM002B-EN-P - September 2013
Chapter 3 Diagnostics and Protection
P463 [InPhase Loss Lvl]
Sets the threshold at which the DC bus voltage ripple triggers an F17 “Input
Phase Loss” fault. Input phase loss is assumed when the DC bus voltage ripple
exceeds the tolerance set by this parameter for a certain time period of time.
Setting a larger value permits a higher bus voltage ripple without causing the drive
to fault but also results in more heating in the bus capacitors shortening their life
or possibly resulting in failure. The default value of 325 is equal to the expected
ripple level for a full rated motor running at half load with single phase input.
This is just a different way of saying that if you know you are going to run single
phase, derate the drive by 50%.
Loading conditions on the motor could also have an effect on this parameter.
Particularly shock loads.
Motor Overload The motor overload protection feature uses an IT (inverse time) algorithm to
model the temperature of the motor and follows the same curve as a physical class
10 overload device.
P26 [Motor NP Amps] is used by the overload feature to establish the 100% level
(y axis) shown in the graph above.
Setting P410 [Motor OL Actn] to zero disables the motor thermal overload. For
multiple motor applications (more than one motor connected to one drive),
separate external overloads for each motor are required, and the drive’s motor
overload can be disabled.
Motor Overload Curve
Full Load Amps (%)
Cold
Hot
Tr
ip
T
im
e
(S
ec
on
ds
)