Fagor 8035-M, Installation Manual

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Installation manual
CNC 8035
CONC
EPTS
Spi
ndl
e
5.
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OFT
M: V15.3
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T: V16.3
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This gain is only to be used when operating with acceleration/deceleration control.
For example, if s.m.p. FFGAIN (P25) has been set to "80", the spindle velocity command will be:
• 80% of it will depend on the programmed feedrate (feed-forward gain)
• 20% of it will depend on the spindle following error (proportional gain)
Setting the Feed-Forward gain involves a critical adjustment of s.m.p. MAXVOLT (P37).
1. Set the spindle at maximum speed and at 10%.
2. Measure the actual analog command at the drive.
3. Set parameter MAXVOLT (P37) to a value 10 times the measured value.
For example, If the measured command voltage was 0.945 V, then set this parameter to 9.45
V, in other words: P37=9450.
Next, set s.m.p. FFGAIN (P25) to the desired value.
Derivative (AC-forward) gain setting
With the derivative gain, it is possible to reduce the following error during the acc./dec. stages.
Its value is given by s.m.p. DERGAIN (P24).
When this additional velocity command is due to fluctuations of following error, "ACFGAIN" (P46)
= NO, it is called "derivative gain".
When it is due to variations of the programmed feedrate, "ACFGAIN" (P42) = YES, it is called AC-
forward gain" since it is due to acc./dec.
Best results are usually obtained when using it as AC-forward Gain, "ACFGAIN" (P42) = YES
together with feed-forward gain.
This gain is only to be used when operating with acceleration/deceleration control.
A practical value between 2 to 3 times the Proportional Gain, "PROGAIN" (P23), may be used.