Mitsubishi Electric MELSEC-L LD75D, User Manual

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770
2-PHASE EXCITATION SYSTEM
This is one system for exciting each stepping motor coil in a determined order. In this system, a current
constantly flows to 2 phases to carry out step feed.
2-SPEED TRAPEZOIDAL CONTROL
In this positioning control method, the positioning pattern, positioning addresses (P1, P2), and positioning
speeds (V1, V2) are set in the program. Positioning is carried out to positioning address P1 by issuing the 1st
positioning start command. When P1 is reached, the positioning then automatically changes to positioning at the
V2 speed.
AFTER mode
This is the mode that outputs the M code after positioning is complete (after stopping). Clamping can be
commanded, drilling dimensions can be selected, etc., with this mode.
BUSY The device is doing some other work. It is in a positioning operation or in dwell time.
CCW (Counterclockwise)
Rotation in the counterclockwise direction. In the motor, this is determined looking from the shaft end side. Also
refer to the term "CW".
CHANGE signal
The CHANGE signal is an external signal used to switch the speed-position control from the speed control being
executed to position control.
CP CONTROL (Continuous Path Control)
Continuous path is a control method in which a path is followed without interrupting such as in uniform speed
control.
CW (Clockwise) Rotation in the clockwise direction. Rotation in the clockwise direction looking from the motor shaft end side.
D/A CONVERTER (Digital-to-Analog
converter)
A device having a function to convert the digital value expressing the No. of pulses to an analog value expressing
the voltage (or current).
DOG SIGNAL The near-point dog of the OPR.
F
In the LD75, F is a status where the module itself has a fault.
[HOLD]
FLS SIGNAL (forward limit signal)
This is the input signal that notifies the user that the limit switch (b contact configuration, normally ON) installed at
the upper limit of the positioning control enabled range has been activated.
The positioning operation stops when the FLS signal turns OFF (non-continuity).
GD
2
The inertia moment. The sum total of the mass (dm) of each small area configuring an object multiplied by the
square of the distance (r) of each of those areas from a given straight line. The relation with I = ∫ r
2
dm GD
2
is
given by 4gI, with "g" being gravitational acceleration.
Term Description
Pulse input
B phase
A phase
A phase
B phase
S
peed
Positioning speed V1
Positioning speed V2
Time
Positioning address P2
Positioning address P1
OFF ON
No.11 No.10
Positioning
M code (8)
Clamp command
No. of pulses
0 to 80,000
pulses/second
D/A Voltage 0 to
±
10V.