Hitachi SJ700D-004L, Instruction Manual

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Chapter 4 Explanation of Functions
4-10
4.2.8 Acceleration/deceleration time setting
- Specify a longer time for slower acceleration or deceleration;
specify a shorter time for quicker acceleration or deceleration.
- The time set with this function is the time to accelerate (or
decelerate) the motor from 0 Hz to the maximum frequency (or vice
versa).
- If you assign the acceleration/deceleration cancellation (LAC)
function to an intelligent input terminal and turns on the terminal,
the set acceleration/deceleration time will be ignored, and the
output frequency will immediately follow the frequency-setting command.
- To switch the acceleration and deceleration time among the 1st, 2nd, and 3rd settings, assign function "08" (SET) and
"17" (SET3) to intelligent input terminals (see Section 4.2.38). Use the SET and SET3 signals for switching.
- As the Accel/decel time input selection by P031, select one of the (1) input from the digital operation, (2) input from
option board 1, (3) input from option board 2, and (4) input from the easy sequence program.
Item Function code Range of data Description
Acceleration (1) time
setting F002/F202/
F302
0.01 to 3600.(s)
Set the length of time to accelerate the motor from 0 Hz
to the maximum frequency.
Deceleration (1) time
setting F003/F203/
F303
0.01 to 3600.(s)
Set the length of time to decelerate the motor from the
maximum frequency to 0 Hz.
Accel/decel time input
selection
P031
00 Input from the digital operator (OPE)
01 Input from option board 1 (OP1)
02 Input from option board 1 (OP2)
03 Input from the easy sequence program (PRG)
Terminal function C001 to C008 46 LAD cancellation
The actual time to accelerate/decelerate the motor will be no less than the minimum acceleration/deceleration time
that depends on the inertial effect (J) due to the mechanical system and motor torque. If you set a time shorter than
the minimum acceleration/deceleration time, the inverter may trip because of overcurrent or overvoltage.
J
L
: Inertia effect (J) of the load converted to that of the motor shaft (kg-m
2
)
J
M
: Inertia effect (J) of the motor (kg-m
2
)
N
M
: Motor speed (rpm)
Ts: Maximum acceleration torque driven by the inverter (N-m)
T
B
: Maximum deceleration torque driven by the inverter (N-m)
T
L
: Required running torque (N-m)
F002/F202/F302: Acceleration (1) time setting,
1st/2nd/3rd motors
F003/F203/F303: Deceleration (1) time setting,
1st/2nd/3rd motors
A004/A204/A304: Maximum frequency setting,
1st/2nd/3rd motors
P031: Accel/decel time input selection
C001 to C008: Terminal [1] to [8] functions
Related code
Maximum frequency
A004/A204/A304
F002/F202/F302 F003/F203/F303
Output frequency
Set output frequency
Actual
acceleration
time
Actual
deceleration
time
Acceleration time (ts)
Deceleration time (t
B
)
t
s
=
(J
L
+ J
M
) × N
M
9.55 x (T
s
- T
L
)
t
B
=
(J
L
+ J
M
) x N
M
9.55 x (T
B
+ T
L
)