Rockwell Automation 20B PowerFlex 70, PowerFlex 700 Reference Manual - Manual (Page 11)

Rockwell Automation Publication PFLEX-RM001H-EN-P - June 2013 11
Chapter
2
Detailed Drive Operation
This chapter explains PowerFlex drive functions in detail. Explanations are
organized alphabetically by topic. Refer to the Table of Contents for a listing of
topics.
Accel Time
[Accel Time 1, 2]
The Accel Time parameters set the rate at which the drive ramps up its output
frequency after a Start command or during an increase in command frequency
(speed change). The rate established is the result of the programmed Accel Time
and the Minimum and Maximum Frequency, as follows:
Two accel times exist to allow the user to change acceleration rates “on the fly” via
PLC command or digital input. The selection is made by programming [Accel
Time 1] & [Accel Time 2] and then using one of the digital inputs ([Digital Inx
Sel]) programmed as “Accel 2” (see
Table 9 for further information). However, if
a PLC is used, manipulate the bits of the command word as shown below.
The effectiveness of these bits or digital inputs can be affected by [Accel Mask].
See
Masks on page 113 for more information.
Times are adjustable in 0.1 second increments from 0.0 seconds to 3600.0
seconds.
In its factory default condition, when no accel select inputs are closed and no
accel time bits are “1,” the default acceleration time is Accel Time 1 and the rate is
determined as above.
Maximum Speed
Accel Time
= Accel Rate (Hz./sec.)
0 1 1 0 0 0 0 1 0 1 1 1
1
0
0
0 Accel 1
Accel 2
Decel 1
Decel 2 0
1
0
0 0
0
1
0 0
0
0
1
0 0 0 0
10 0 1 2 3 4 5 6 7 8 9 11 12 13 14 15
1 = Condition True
0 = Condition False
x = Reserved
Bit #
Stop Star
t
Jo
g
Clear F
ault
Forwar
d
Re
ver
se
Local Contrl Mop Inc Accel 1 Accel 2 Decel 1 Decel 2 Spd Ref ID 0
(1)
Spd Ref ID 1
(1)
Spd Ref ID 2
(1)
MOP Dec