Rockwell Automation 20G PowerFlex 750-Series AC Drives - Manual (Page 220)

220 Rockwell Automation Publication 750-RM002B-EN-P - September 2013
Chapter 4 Motor Control
Parameters
Applications
This function is usually associated with applications that require extended
acceleration times. Out of the box, the drive is set to “Automatic” and attempts to
get full motor stator flux based on motor nameplate information. In some cases
the loading and ramp curve during acceleration could have an adverse affect on
the drive's thermal manager. Some applications include mining conveyors or large
centrifuges. This function gives you the ability to manually be sure the motor
stator is fully fluxed up before acceleration by manually assigning a flux up time. It
can produce a better acceleration at low frequencies without excessive current.
High Resolution Feedback The Universal Feedback option module, PowerFlex 755 drives only, interpolates
any sine/cosine signal into 1,048,576 counts per revolution.
The interpolation cannot be changed. It is 1,048,576 counts per revolution
regardless of the native cycles per revolution of the sine/cosine. Interpolation is
modified to 24 bits when P8 [FB0 Cfg] or P38 [FB1 Cfg] Bit 1 “24-bit Resol” is
set.
An acceptable sine/cosine signal is a 1 volt peak-to-peak voltage with a 2.5 volt
offset. Most feedback manufactures Sick (SSI), Stegmann (Hiperface), and
Heidenhain (En Dat, non en dat) meet this requirement.
Fil
e
Gr
oup
No. Display Name
Full Name
Description Values
Re
ad
-Write
Da
ta
T
yp
e
MOT
O
R CONTROL
Mt
r Ctr
l O
pti
on
s
43 Flux Up Enable
Flux Up Enable
“Manual” (0) – Flux is established for P44 [Flux Up Time] before initial acceleration.
“Automatic” (1) – Flux is established for a calculated time period based on motor
nameplate data before acceleration. P44 [Flux Up Time] is not used. Default:
Options: 1 = “Automatic”
0 = “Manual”
1 = “Automatic” RW 32-bit
Integer
44 Flux Up Time
Flux Up Time
The amount of time the drive will use to try to achieve full motor stator flux. When a
Start command is issued, DC current at P26 [Motor NP Amps] level is used to build stator
flux before accelerating. Units:
Default:
Min/Max: Secs
0.0000
0.0000 / 5.0000 RW Real