MITSUBISHI ELECTRIC MOTION CONTROLLERS Q172DCPU - Manual (Page 101)

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4 AUXILIARY AND APPLIED FUNCTIONS
4.2.1 Current value control
The current value when using the ABS encoder is controlled by following functions.
(1) The validity of an encoder data during operation is checked.
(a) Checks that the amount of change of the encoder in a 3.5[ms] is within 180
degrees at the motor axis. (An error is displayed at the abnormal.)
(b) Checks that adjustment of the encoder data and feed-back positions
controlled with the servo amplifier. (An error is displayed at the abnormal.)
(2) The following values can be monitored by the current value history monitor of
MT Developer.
Monitor conditions Monitor value
Multiple CPU system power ON/OFF
Home position return completion
Encoder current value,
Servo command value,
Monitor current value
(a) Current value history monitor
Month/day/hour/minute
The time such as at the completion of home position return and servo
amplifier power supply ON/OFF is indicated.
In order to indicate the time correctly, turn on SM801 (clock data read
request) in the Motion SFC program after setting the clock data of
special register.
(b) Encoder current value
When using the MR-J3- B, the multiple revolution data and within-one-
revolution data read from the encoder is indicated.
(Note) : For the encoder current value in the home position data area, the
encoder current value when the motor is within the in-position range
at the completion of home position return is displayed (not encoder
value of home position).
(c) Servo command value
The command value issued to the servo amplifier is indicated.
(d) Monitor current value
The current value controlled in the Motion CPU is indicated.
(Note) : A value near the feed current value is indicated. However, because
the monitor current value and feed current value are different data, it
is not abnormal even if a different value is indicated.
(e) Alarms
When an error for current value restoration occurs at the servo amplifier
power on, an error code is indicated.
(3) By setting of the "Allowable travel during power off", if the encoder data changes
exceeding the setting range during power-off, it checks at servo amplifier power-
on. (An error is displayed at the abnormal.)
"Allowable travel during power off" cannot be set for the Linear servo amplifier.