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Chapter 4. Functions
z
Control method
The setting is valid if a MOTOR block is inserted (using four slots) into the I/O slot.
The control method of the motor drive output can be set.
Item (bank)
Display
Description
Initial value
Control method selection
PP (position proportional) bank
MENU > PP
Selection of control
method
0: MFB c estimated position control
1: MFB c close upon line break
2: Estimated position control
3: Estimated position c position
adjustment at power-on
0
z
z
Setting 0 (MFB c estimated position control)
When the MFB (motor feedback) input is normal, motor drive output is controlled
at the actual-measured MFB opening. If the MFB input is abnormal, motor drive
output is controlled at the estimated MFB opening. The latter status is called
"Estimating MFB."
•
If the motor rotates to a position where the feedback potentiometer has
deteriorated, the MFB input changes suddenly. This sudden change is detected as
an abnormality, and the status changes to Estimating MFB. Estimating MFB also
occurs when an MFB input wiring disconnection is detected.
•
While the MFB is being estimated, standard bit code 1888 ("Estimating MFB")
changes to 1. It is 0 at all other times.
z
z
Setting 1 (MFB c close upon line break)
Motor drive output is controlled at the actually measured MFB opening. When an
MFB input wiring disconnection is detected, the CLOSE-side relay remains always
ON.
•
The status does not change to Estimating MFB. Standard bit code 1888
("Estimating MFB") is 0.
z
z
Setting 2 (Estimated position control)
The motor drive output is controlled at the estimated MFB opening regardless of
the wiring connection for MFB input.
•
The status is always Estimating MFB. Standard bit code 1888 ("Estimating MFB")
is 1.
•
The status does not change to MFB input wiring disconnection.
•
The error between the actual MFB opening and estimated MFB opening is
corrected by turning on the CLOSE-side relay when output (MV) ≤ 0.0 % and
turning on the OPEN-side relay when output (MV) ≥ 100.0 %.
z
z
Setting 3 (Estimated position c position adjustment at power-on)
The error between the actual MFB opening and estimated MFB opening is
corrected by turning on the CLOSE-side relay for the duration of the "Full opening
time" only when the power is turned on. Subsequent operation is identical to the
case for Setting 2.