Mitsubishi Electric FR-A700 Technical Manual page 48

1.4.5 Run and stop (STF, STR, STOP)
To start and stop the motor, first switch ON the input power
of the inverter (turn ON the MC at the operation-ready
when there is an MC on the input side). Then start the
motor with the forward or reverse rotation start signal.
(1) Two-wire type (STF, STR)
A two-wire type connection is shown below.
1) Forward/reverse rotation signal is used as both
the start and stop signals. Turn ON either of the
forward and reverse rotation signals to start the
motor in the corresponding direction. Switching
ON or OFF both the start signals during operation
will decelerate the inverter to a stop.
2) The speed setting signals may either be given by
entering 0 to 5VDC across the frequency setting
input terminal 2-5, by setting three speed [Pr. 4 to
Pr. 6] (high, middle, low speeds), etc.
(For multi-speed operation, refer to page 48.)
3) After the start signal has been input, the inverter
starts operating when the frequency setting signal
reaches or exceeds the [Pr. 13 Starting frequency].
If the motor load torque is large or the [Pr. 0 Torque
boost] setting is small, operation may not be
started due to insufficient torque until the inverter
output frequency reaches about 3 to 6Hz.
If the [Pr. 2 Minimum frequency] is set to 6Hz, for
example, merely entering the start signal causes
the running frequency to reach the minimum
frequency of 6Hz according to the [Pr. 7
Acceleration time].
4) To stop the motor, operate the DC injection brake
for the period of time set in [Pr. 11 DC injection
brake operation time] at not more than the DC
injection brake operation frequency or at not more
than 0.5Hz.
To disable the DC injection brake function, set 0 in
either of [Pr. 11 DC injection brake operation time] or
[Pr. 12 DC injection brake voltage].
In this case, the motor is coasted to a stop at not
more than the frequency set in [Pr. 10 DC injection
brake operation frequency] or at not more than
0.5Hz (when the DC injection brake is not
operated).
5) If the reverse rotation signal is input during
forward rotation or the forward rotation signal is
Forward
STF
rotation start
STR Inverter
Reverse
rotation start
SD
10
2
5
Time
ON
STF
ON
STR
Two wire-type connection
([Pr. 250 = 9999])
common
(common
common
Start signal STF
STR Inverter
Forward/
reverse
SD
signal
10
2
5
Time
ON
STF
ON
STR
Two wire-type connection
([Pr. 250 = 8888])
41
)
input during
characteristics change without going through the
stop mode.
(2) Three-wire type connection (STF, STR,
STOP)
common
A three-wire type connection is shown below.
1) Turn ON the STOP signal to enable the start self-
holding function. In this case, the forward/reverse
rotation signal functions only as a start signal.
2) If the start signals STF (STR) are turned ON once,
then OFF, the start signals are kept ON and starts
the inverter. When changing the direction of
rotation, turn STR (STF) signal ON once and then
OFF.
3) The inverter is decelerated to a stop by turning
OFF the STOP signal once. For the frequency
setting signal and the operation of DC injection
brake at a stop time, refer to paragraphs 2) to 4) in
(1) Two-wire type connection.
4) When the signal JOG is turned ON, terminal
STOP signal is invalid and JOG operation has
precedence.
5) If MRS signal is turned ON, the self-holding
function is not deactivated.
(3) Start signal selection
[Pr. 250] Setting Inverter State
STF STR
0 to 100s, 9999
OFF OFF
OFF ON Reverse rotation
ON OFF Forward rotation
ON ON
Forward
Stop
rotation start
STF
Inverter
Reverse
rotation start
STR
STOP
SD
Time
ON
STF
ON
STR
STOP
ON ON
OFF
OFF
Three wire-type connection
Example
[Pr. 250 = 9999]
SPECIFICATIONS
reverse rotation, output
1000 to 1100s,
8888
Stop
Stop
Forward rotation
Stop Reverse rotation
Stop
Start
STF
Inverter
STOP
STR
Forward rotation
/reverse rotation
SD
Time
ON ON
STF
STR ON
STOP ON
OFF OFF
Three wire-type connection
Example
([Pr. 250 = 8888])
1