Mitsubishi Electric FR-E700 Instruction Manual page 232

Acceleration and deceleration
S-pattern acceleration/deceleration A (Pr. 29 = "1")
For machine tool spindle applications, etc.
Used when acceleration/deceleration must be made in a short time to a high-speed range of not low-
er than base frequency. In this acceleration/deceleration pattern, Pr. 3 "Base frequency" (fb) is the in-
flection point of the S-pattern (refer to 6-34) and you can set the acceleration/deceleration time ap-
propriate for motor torque reduction in a constant-output operation region of base frequency or
higher.
S-pattern acceleration/deceleration B (Pr. 29 = "2")
When a setting of "2" is entered frequency changes are executed with an S-pattern. For example, if a
drive is accelerated from 0 to 30 Hz and then re-accelerated to 50 Hz then each acceleration sequence
(i.e. the first sequence from 0 to 30 Hz and the second from 30 Hz to 50 Hz) will be executed with an
S-pattern. The time for the S-pattern is not longer than that for linear acceleration (refer to 6-35). This
prevents jolts in drive operation, for example for conveyor belt and positioning drive systems.
NOTE
As the acceleration/deceleration time of S-pattern acceleration/deceleration A, set the time taken
until Pr. 3 "Base frequency" is reached, not Pr. 20 "Acceleration/deceleration reference frequency".
6 - 78
S-pattern acceleration/
deceleration A
Time
S-pattern acceleration/
deceleration B
Time
Fig. 6-34:
Characteristic for parameter 29 = "1"
Fig. 6-35:
Characteristic for parameter 29 = "2"
Parameter
I000016C
I000017C