Mitsubishi Electronics MR-J2S- A Outline 15.1.1 Features, Restrictions, Cpu, Lso, 1XO

15.ABSOLUTE POSITION DETECTION SYSTEM

15.ABSOLUTE POSITION DETECTION SYSTEM

15.1Outline 15.1.1 Features

For normal operation, as shown below, the encoder consists of a detector designed to detect a position within one revolution and a cumulative revolution counter designed to detect the number of revolutions. The absolute position detection system always detects the absolute position of the machine and keeps it battery-backed, independently of whether the general-purpose programming controller power is on or off. Therefore, once the home position is defined at the time of machine installation, home position return is not needed when power is switched on thereafter.

If a power failure or a fault occurs, restoration is easy.

Also, the absolute position data, which is battery-backed by the super capacitor in the encoder, can be retained within the specified period (cumulative revolution counter value retaining time) if the cable is unplugged or broken.

General purpose programmable	Servo amplifier
controller

CPU

Changing the current position data

Positioning module	Pulse train
	(command) Home position data

Current		EEPROM memory			Current		Position control
position								Speed control
		LSO			position
data
		1XO			data
I/O module		Backed up in the
	Input	case of power failure		LS		1X
				Detecting the		Detecting the
				number of		position within
				revolutions		one revolution
	Output	Battery	MR-BAT
Servo motor
	1 pulse/rev Accumulative					High speed serial
	revolution counter
		Super capacitor				communication
	Within-one-revolution counter
	A, B, Z phase signals

(Position detector)

15.1.2 Restrictions

The absolute position detection system cannot be configured under the following conditions. Test operation cannot be performed in the absolute position detection system, either. To perform test operation, choose incremental in parameter No.1.

(1)Speed control mode, torque control mode.

(2)Control switch-over mode (position/speed, speed/torque, torque/speed).

(3)Stroke-less coordinate system, e.g. rotary shaft, infinitely long positioning.

(4)Changing of electronic gear after home position setting.

(5)Use of alarm code output.

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