Mitsubishi Electronics Mitsubishi Digital Electronics Automobile Accessories Frequency Inverter Benutzerhandbuch
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MITSUBISHI ELECTRIC
FR-F 740 EC/E1
Extended PID control
The FR-F 740 series supports extended PID
control. This feature makes it possible to
connect the process status signal to the fre-
quency inverter as a voltage signal
(0–10 V DC) or a current signal
(0/4–20 mA DC) and then use the analog
input calibration function of the inverter to
compensate minor controller-related fluc-
tuations.
control. This feature makes it possible to
connect the process status signal to the fre-
quency inverter as a voltage signal
(0–10 V DC) or a current signal
(0/4–20 mA DC) and then use the analog
input calibration function of the inverter to
compensate minor controller-related fluc-
tuations.
In addition to this the frequency inverter
can also control up to four motors succes-
sively. This function is programmable; for
example, you can program it so that only
one motor is frequency-controlled and the
others are switched on and off under direct
mains power as required, or you can alter-
nate between direct mains power and
frequency control for all four motors.
can also control up to four motors succes-
sively. This function is programmable; for
example, you can program it so that only
one motor is frequency-controlled and the
others are switched on and off under direct
mains power as required, or you can alter-
nate between direct mains power and
frequency control for all four motors.
The graph on the right illustrates this multi-
motor switching function with a typical ex-
ample.
motor switching function with a typical ex-
ample.
When implementing an application like
this you must plan the necessary number
of magnetic power contactors and the re-
quired number of output signal terminals
on the inverter. Care must also be taken to
ensure that the mains power is never swit-
ched to the inverter output.
this you must plan the necessary number
of magnetic power contactors and the re-
quired number of output signal terminals
on the inverter. Care must also be taken to
ensure that the mains power is never swit-
ched to the inverter output.
Motor 1 (M1)
Motor 2 (M2)
Motor 3 (M3)
Motor 4 (M4)
Motor 1 (M1)
Motor 2 (M2)
Motor 3 (M3)
Motor 4 (M4)
Motor 1 (M1)
Motor 2 (M2)
Motor 3 (M3)
Motor 4 (M4)
Motor 1 (M1)
Motor 2 (M2)
Motor 3 (M3)
Motor 4 (M4)
*2
*1
*2
*1
Q max
Q 3
Q 2
Q 1
Inverter controlled operation
Conventional operation
Stop
Time
*
*
Flow rate
* After switching the magnetic contactor the motor start
sequence switches from M1->M2->M3 to M2->M3->M1
Intelligent Motor Control Functions
Flexible 5-point V/f curve
The integrated flexible 5-point V/f curve
enables you to match the torque curve
perfectly to the characteristics of your
machine.
enables you to match the torque curve
perfectly to the characteristics of your
machine.
Together, the optimum excitation control
feature and the 5-point V/f curve achieve
significantly increased power savings.
feature and the 5-point V/f curve achieve
significantly increased power savings.
Automatic restart after instantane-
ous power failures
ous power failures
In pump and fan applications normal ope-
ration can be continued automatically af-
ter brief power failures. The system simply
reactivates the coasting motor and auto-
matically accelerates it back up to its
setpoint speed.
ration can be continued automatically af-
ter brief power failures. The system simply
reactivates the coasting motor and auto-
matically accelerates it back up to its
setpoint speed.
The graphic on the right shows how the
frequency inverter can respond to a brief
power outage. Instead of coasting down
completely and stopping, the motor is au-
tomatically “caught” by the frequency in-
verter and re-accelerated back up to its
previous speed.
frequency inverter can respond to a brief
power outage. Instead of coasting down
completely and stopping, the motor is au-
tomatically “caught” by the frequency in-
verter and re-accelerated back up to its
previous speed.
0
V/F5
V/F4
V/F3
V/F2
V/F1
Base frequency
V/f pattern
Torque
characteristic
characteristic
Volt
age
V/f characteristic
IPF
Restart
acceleration
acceleration
Deceleration
Power supply
Output frequency
SYSTEM DESCRIPTION