Appendix - 49
MELSEC-
A
APPENDICES
Appendix 12 Positioning control troubleshooting
Trouble type Questions/Trouble Remedy No.
Parameter
Display reads "FFFF
H" when a
parameter is read with a AD75
software package.
The PLC CPU power was turned OFF or the PLC CPU
was reset, etc., during flash ROM writing, which deleted
the data in the flash ROM.
Initialize the parameters, and reset the required
parameters.
(Refer to section "13.2 Parameter initialization function"
for details.)
1
How can the parameters be
returned to their initial values ?
Set the
Cd.10
Parameter initialization request to "1".
(Refer to section "13.2 Parameter initialization function"
for details.)
2
A parameter error occurred
although the parameter was set
correctly in the AD75 software
package.
The parameter may have been overwritten in the
sequence program.
Review the sequence program.
3
Hardware stroke limit
The machine overruns if operating
at high speeds when the hardware
stroke limit range is exceeded.
In the D75P2, deceleration stops are executed after the
machine exceeds hardware stroke limit range. Because of
this, more time is required for the deceleration stop as the
speed increases, and the overrun becomes larger.
(The deceleration time becomes shorter at lower speeds,
so the overrun becomes smaller.)
4
When the machine exceeded the
hardware stroke limit range,
positioning toward inside the range
was started, but the machine did
not start.
Use a "JOG operation" or "Manual pulse generator
operation" to return the machine to inside the hardware
stroke limit range.
(When the hardware stroke limit range is exceeded,
positioning will not start toward inside the range even
when so commanded. Once the range is exceeded, a
return to inside the range can only be executed using a
"JOG operation" or "Manual pulse generator operation".)
5
Degree
Exactly one rotation is required,
but the setting range for a "degree"
unit setting is "0 to 359.999...".
Won't the rotation deviate by
"0.00...1"?
Designate "360.000" in the INC control.
The motor will make exactly one rotation.
6
Movement amount
per pulse
If the "movement amount per
pulse" is calculated as written in
the manual, settings smaller than
the basic parameter setting range
cannot be carried out.
Set "movement amount per pulse" in the D75P2 using the
three parameter values of
Pr.2 to Pr.4 .
Try setting the values following the explanations for each
parameter.
7
Override
Will an override setting value
written before starting be valid?
It will be valid. 8
During tracking control, will the
override still be valid after the point
is passed?
It will still be valid. 9
How can the override be
canceled?
Set the "Positioning operation speed override (RWwm+1,
RWwm+9)" to "100".
10