Mitsubishi Electric FR-F740 EC Instruction Manual page 228

Acceleration and deceleration
frequency
Pr. 147
RT signal
Fig. 6-31:
S-shaped acceleration/deceleration pattern
If a S-shaped acceleration/deceleration pattern A is selected in pr. 29, the set time is the period
required to reach the base frequency set in Pr. 3 "Base frequency".
Acceleration/deceleration time formula when the set frequency is the base frequency or higher.
4
×
t = -- -
9
T: Acceleration/deceleration time setting value (s)
f: Set frequency (Hz)
Guideline for acceleration/deceleration time when Pr. 3 Base frequency = 50Hz (0Hz to set fre-
quency).
Acceleration/deceleration
time [s]
Tab. 6-8:
NOTES The RT signal is assigned to the RT terminal in the default setting. By setting "3" to any of
Pr. 178 to Pr. 189 "Input terminal function selection", you can assign the RT signal to the
other terminal.
The RT signal can be assigned to the input terminal using any of Pr. 178 to Pr. 189 "Input
terminal function selection". When terminal assignment is changed, the other functions may
be affected. Please make setting after confirming the function of each terminal.
If the Pr. 20 setting is changed, the Pr. 125 and Pr. 126 (frequency setting signal gain fre-
quency) settings do not change. Set Pr. 125 and Pr. 126 to adjust the gains.
When the Pr. 7, Pr. 8, Pr. 44 and Pr. 45 settings are 0.03s or less, the acceleration/deceler-
ation time is 0.04s. At that time, set Pr. 20 to "120Hz" or less.
If the acceleration/deceleration time is set, the actual motor acceleration/deceleration time
cannot be made shorter than the shortest acceleration/deceleration time determined by the
mechanical system J (inertia moment) and motor torque.
6 - 78
Output frequency [Hz]
Set
Pr. 7 Pr. 44
ON
Automatic switching of the acceleration/deceleration time
T
5
2
×
------------------- - f + -- - T
2
9
( )
Pr. 3
Frequency Setting [Hz]
5
15
Acceleration/deceleration time at a base frequency of 50Hz
Pr. 44 Pr. 8 Pr. 7
(Pr. 45)
50 120
5 16
15 47
Pr. 44 Pr. 44 Pr. 8
(Pr. 45)
200
38
115
Parameter
Time
I001929E
400
145
435