Rockwell Automation 21G PowerFlex 750-Series AC Drives Programming Manual - Manual (Page 459)

Rockwell Automation Publication 750-PM001J-EN-P - October 2014 459
Application Notes Appendix B
Inertia Tune
The Inertia Tune routine measures the time to accelerate the system (with load)
using P71 [Autotune Torque] to the nominal speed. The test speed can be
limited by reducing P520 [Max Fwd Speed] and P521 [Max Rev Speed]. The
fastest test is achieved with P71 [Autotune Torque] set to a high value and P520
[Max Fwd Speed] and P521 [Max Rev Speed] set to a low value.
Because loading varies in crane applications, the result of an Inertia Tune is more
or less irrelevant as it is for one condition only.
Step 8 outlines manually setting tuning values.
1. Enter Inertia Tune parameter settings.
2. Press the Start button on the Control Bar.
When the Rotate Tune routine is complete, P70 [Autotune] changes to 0
“Ready.”
Check tuning results in P76 [Total Inertia].
3. Set minimum speed.
4. Set maximum speed limits.
5. Set digital input functions.
Speed Select Inputs
Clear Fault Input
IMPORTANT Ensure that the Inertia Tune routine can be stopped if an end travel condition is
likely to occur.
Drive Parameter Setting
P70 [Autotune] 4 “Inertia Tune”
Drive Parameter Setting
P522 [Min Fwd Speed] 2 x Slip Frequency of Motor. (From motor nameplate.)
P523 [Min Rev Speed] 2 x Slip Frequency of Motor. (From motor nameplate.)
Drive Parameter Setting
P520 [Max Fwd Speed] Forward speed limit that is used during normal operation.
Not more than the motor nominal frequency.
P521 [Max Rev Speed] Reverse speed limit that is used during normal operation.
Not more than the motor nominal frequency.
Drive Parameter Setting
P173…175 [DI Speed Sel n] I/O Port Number, P1 [Dig In Sts], Bit n
Drive Parameter Setting
P156 [DI Clear Fault] I/O Port Number, P1 [Dig In Sts], Bit n