Scale Measurement Function; Functions And Configuration - Mitsubishi Electric MELSERVO-J3 Series Manual

Part 5: Common Reference Material

6.3 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.

6.3.1 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 the scale measurement function is used for MR-J4-_B_or MR-J4W2-_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 "MR-J4-_B_ Servo Amplifier
Instruction Manual" or "MR-J4W2-_B Servo Amplifier Instruction Manual".
The scale measurement function compatible servo amplifier can be used with
any of the following controllers.
Motion controller R_MTCPU/Q17_DSCPU
Simple motion module RD77MS/QD77MS_/LD77MS_
(The MR-J4W2-_B servo amplifiers are not available with simple Motion
module.)
For settings and restrictions 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)
5 - 170
Servo motor
Scale measurement encoder
Encoder pulse setting
([Pr.PA15], [Pr.PA16]
and [Pr. PC03])