Inertia tune – Rockwell Automation 21G PowerFlex 750-Series AC Drives Programming Manual User Manual

Page 450

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450

Rockwell Automation Publication 750-PM001J-EN-P - October 2014

Appendix B

Application Notes

1.

Enter Rotate 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 P73 [IR Voltage Drop], P74 Ixo Voltage Drop],
and P75 [Flux Current Ref ].

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].

When using an encoder, the drive and motor can hold zero speed with full
load even with an opened mechanical brake.

Drive Parameter

Setting

P70 [Autotune]

3 “Rotate Tune”

P520 [Max Fwd Speed]

Forward speed limit that is used during Autotune.
70% P27 [Motor NP Hertz] minimum.

P521 [Max Rev Speed]

Reverse speed limit that is used during Autotune.
70% P27 [Motor NP Hertz] minimum.

Encoder Module Parameter (Port X)

Setting

P10 [RO0 Sel]

Port 0, P935 [Drive Status 1], Bit 1 “Active”

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”

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