Mitsubishi Electric FR-A700 Instruction Manual page 457

Parameter
Please observe the following points when an encoder is used for orientation under V/f control or
advanced magnetic flux vector control.
● The encoder should be coupled with the motor shaft or main spindle oriented with a speed
ratio of 1 to 1 without any mechanical looseness.
● DC injection brake operates when orientation stop is made. Release the DC injection brake
in a time as short as possible (within several seconds) since continuous operation of the DC
injection brake will cause the motor to overheat, leading to burnout.
● Since no servo lock function is available after orientation stop, provide a holding mechanism
such as mechanical brake or knock pin when secure holding of a main spindle is required.
● To ensure correct positioning, the encoder must be set in the proper rotation direction and
the A and B phases connected correctly.
● When the pulse signal from the encoder stops due to the encoder signal loss, etc. during
orientation, the orientation fault signal (ORM) may be output.
● When the DC injection brake is set to disabled using parameter for DC injection brake
adjustment (voltage, frequency, speed, time) when performing orientation control, orienta-
tion operation can not be completed. Always set the DC injection brake enabled.
● To terminate orientation, the start signal (STF or STR) must be first switched off and the
orientation signal (X22) must be switched off. As soon as this orientation signal is switched
off, orientation control ends.(Depending on the Pr. 358 "Servo torque selection" setting,
orientation status continues if the orientation signal remains on even if DC injection brake
is released at turning off of the start signal. Therefore, the orientation status of the monitor
function is not 0.)
● When retry function of Pr. 358 "Servo torque selection" is selected, this retry function is
performed three times including the first orientation.
● When performing orientation control, make proper setting of Pr. 350 "Stop position command
selection" and Pr. 360 "16 bit data selection (external position command selection)". If the
values set are incorrect, proper orientation control will not be performed.
● When Pr. 11 "DC injection brake operation time" = "8888" (DC injection brake external
selection), DC injection brake does not operate if the X13 signal is not turned on. Note that
the DC injection brake is applied under orientation control regardless of the X13 signal
status.
● When orientation control is exercised, PID control is invalid.
FR-A700 EC
Motor brake and stop operation
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