Mitsubishi Electric Melsec FX Series Beginners Manual page 30

Components of Positioning Control and their Roles
Operation switch
Fig. 3-1: Components of Postioning Control (1)
3 - 2
Postion controller
Outputs the positioning speed and the
movement quantity in command pulses to the
servo amplifier.
Transfers signals between the programmable
controller.
Controls return to the zero point.
Nearpoint DOG signal
In some types, the limit switch signal
is wired to the position controller
Main circuit
Position controller
Positioning
command
control Command
pulse
Parameter
Zero point
return
control
Servo
ready
10
Manual pulse generator
Operation equipment
Gives inputs for manual/automatic mode, start/stop, zero
point return command, manual forward rotation/reverse
rotation and manual pulse generator to the positioning
controller.
AC power
supply
Breaker
Smoothing
Converter
circuit
AC DC DC
Speed
command
Pulse
Deviation
magnification counter
Current
(Electronic gear)
control
Counter clear
Zero point signal (PGO)
Servo amplifier
Rectifies the AC power of the main circuit into the DC power in the
converter, and smooths it in the smoothing circuit. When the DC power is
converted into AC power in the inverter, the current supplied to the servo
motor is changed by the PWM (pulse width modulation) control in the
control circuit.
The deviation counter receives and counts the command pulses from the
positioning controller, subtracts the feedback pulses from them, then
drives the servo motor until the accumulated pulse number becomes 0.
Power factor
improving AG
Electromagnetic Line noise
contactor filter
Powerboard
Improves the power factor and cuts noise.
Protects the power circuit.
Servo amplifier
Regenerative
Inverter
brake
DC AC
Feedback
current
PWM (pulse width
modulation) control
Feedback pulse
MITSUBISHI ELECTRIC
Radio noise
reactor filter
Dynamic
brake
R
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