Scale Measurement Function - Mitsubishi Electric MELSERVO-J4 series Instruction Manual

17. APPLICATION OF FUNCTIONS

17.3 Scale measurement function

The scale measurement function transmits position information of a scale measurement encoder to the
controller by connecting the scale measurement encoder in semi closed loop control.
17.3.1 Functions and configuration
(1) Function block diagram
The following shows a block diagram of the scale measurement function. The control will be performed
per servo motor encoder unit for the scale measurement function.
Controller
(Servo motor)
Droop pulses
(Servo motor)
Cumulative
feedback pulses
Cumulative
load-side
feedback pulses
POINT
The scale measurement function is available for the servo amplifiers of software
version A8 or later.
When a linear encoder is used as a scale measurement encoder for this servo
amplifier, "Linear Encoder Instruction Manual" is necessary.
When the scale measurement function is used for MR-J4-_B_ servo amplifiers,
the following restrictions apply. However, these restrictions will not be applied for
MR-J4-_B_-RJ servo amplifiers.
A/B/Z-phase differential output type encoder cannot be used.
The scale measurement encoder and servo motor encoder are compatible
with only the two-wire type. The four-wire type scale measurement encoder
and servo motor encoder cannot be used.
When you use the HG-KR and HG-MR series for driving and scale
measurement encoder, the optional four-wire type encoder cables (MR-
EKCBL30M-L, MR-EKCBL30M-H, MR-EKCBL40M-H, and MR-EKCBL50M-H)
cannot be used. When an encoder cable of 30 m to 50 m is needed, fabricate
a two-wire type encoder cable according to appendix 9.
The scale measurement function compatible servo amplifier can be used with
any of the following controllers.
Motion controller Q17nDSCPU
Simple motion module QD77MS_
For settings of controllers compatible with the scale measurement function, refer
to user's manuals for each controller.
+
-
+
Servo motor feedback pulses
(Servo motor resolution unit)
-
Control
Monitor
+
-
S
Load-side feedback pulses
(Scale resolution unit)
17 - 15
Servo motor
Scale measurement encoder
Encoder pulse setting
([Pr.PA15], [Pr.PA16]
and [Pr. PC03])