Mitsubishi Electric FR-A700 Technical Manual page 283

2.11.6 Setting of positioning adjustment parameter [Pr. 426, 427]
[Pr. ] Name
426
In-position width
427
Excessive level error
* When the operation panel (FR-DU07) is used, the maximum setting is 9999. When a parameter unit is used, up to the maximum
value within the setting range can be set.
(1) In-position width [Pr. 426]
The Y36 signal acts as an in-position signal. When
the number of droop pulses has fallen below the
setting value, the in-position signal (Y36) turns ON.
For the Y36 signal, assign the function by setting 36
(positive logic) or 136 (negative logic) in any of [Pr.
190 to 196 Output terminal function selection] .
2.11.7 Gain adjustment [Pr. 422, 423, 425]
Easy gain tuning is available as an easy tuning method.
Refer to page 286 for easy gain tuning.
If easy gain tuning does not produce any effect, make fine
adjustment by using the following parameters.
[Pr. ] Name
422
Position loop gain
Position feed forward
423
gain
Position feed forward
425
command filter
(1) Position loop gain [Pr. 422]
Make adjustment when any of unusual vibration,
noise and overcurrent of the motor/machine occurs.
Increasing the setting improves response for the
position command and also improves servo rigidity at
a stop, but oppositely makes an overshoot and
vibration more liable to occur.
Normally set this parameter within the range about 5
to 50.
Phenomenon/
Adjustment Method
Condition
Increase the [Pr. 422] setting by 3s
before an overshoot or instable behavior
Slow response
such as stop-time vibration occurs, and set
about 0.8 to 0.9 of that value.
Overshoot, stop-
Decrease the [Pr. 422] setting by 3s
time vibration or
before an overshoot or instable behavior
other instable
such as stop-time vibration does not occur,
behavior occurs.
and set about 0.8 to 0.9 of that value.
Initial Value Setting Range
100 pulses 0 to 32767 pulses
0 to 400
40
9999
(2) Excessive level error [Pr. 427]
A700
(A700)
Set [Pr. 819 Easy gain tuning = 0] before setting the
parameters below.
Setting
Initial Value
Range
-1 -1
25s 0 to 150s
0% 0 to 100%
0s 0 to 5s
(2) Position feed forward gain [Pr. 423]
-1
until just
-1
until just
317
A700
(A700)
Description
When the number of droop pulses has fallen below the
*
setting value, the in-position signal (Y36) turns ON.
A position error excessive (E.OD) occurs when the
number of droop pulses exceeds the setting.
Function invalid
When droop pulses exceed the value set in [Pr. 427],
position error becomes large, and a fault (E.OD) is
displayed to stop the inverter. When you decrease
the position loop gain [Pr. 422 Position loop gain]
setting, increase the error excessive level setting.
Also decrease the setting when you want to detect an
error slightly earlier under large load.
When [Pr. 427 = 9999], position error large (E.OD)
does not occur regardless of droop pulses.
Description
Set the gain of the position loop.
Function to cancel a delay caused by the droop pulses
of the deviation counter.
Enters the primary delay filter in response to the feed
forward command.
This function is designed to cancel a delay caused by
the droop pulses of the deviation counter.
When a tracking delay for command pulses poses a
problem, increase the setting gradually and use this
parameter within the range where an overshoot or
vibration will not occur.
This function has no effects on servo rigidity at a
stop.
Normally set this parameter to 0.
PARAMETER
2