Item	Specifications
Model	CJ1W-NC271/471/F71 (-MA)
Internal current consumption	360 mA max. at 5 V DC
Dimensions	31 × 90 × 65 mm (W × H × D)
Weight	95 g max.
Ambient operating temperature	0 to 55°C
Approved standards	CE, cULus, and C-tick

Specifications not listed above conform to general CJ Series specifications.

Functions and Specifications

Item		Specifications
Unit classification		CPU Bus Unit
Applicable PLCs		CJ Series
Possible unit number settings		0 to F
I/O allocations	Common Operating Memory Area	Words allocated in CPU Bus Unit Area: 25 words (15 output words, 10 input words)
I/O allocations	Axis Operating Memory Area	Allocated in one of the following areas (user-specified): CIO, Work, Auxiliary, Holding, DM, or EM Area. Number of words allocated: 50 words (25 output words, 25 input words) × Highest axis No. used
Compatible devices		OMRON G5-series Servo Drives (Built-in MECHATROLINK-II communications) OMRON G-series Servo Drives (Built-in MECHATROLINK-II communications)
Control method		Control commands executed using MECHATROLINK-II synchronous communications.
Maximum number of controlled axes		CJ1W-NC271: 2 axes, CJ1W-NC471: 4 axes, CJ1W-NCF71: 16 axes
Control units	Position command unit	Command unit:Depends on the Electronic Gear Setting in the Servo Parameters. Default setting: Pulses
	Speed command unit for position control	Command units/s
	Acceleration/ deceleration speeds for position control	10,000 command units/s2
	Speed command unit for speed control	0.001% of the motor’s momentary maximum rotation speed
	Torque command unit for torque control	0.001% of the motor’s momentary maximum torque
Control command range	Position command range	2,147,483,648 to 2,147,483,647 (command units)
	Speed command range for position control	0 to 2,147,483,647 (command units/s)
	Acceleration/ deceleration speeds for position control	1 to 65,535 (10,000 command units/s2)
	Speed command range for speed control	-199.999% to 199.999% The upper limit of the speed command range depends on the specifications of the Servo Drive.
	Torque command range for torque control	-199.999% to 199.999% The upper limit of the torque command range depends on the specifications of the Servo Drive.
Control functions	Servo lock/unlock	Creates (Servo lock) or releases (Servo unlock) the position loop on the PCU.
	Position control	Positions to an absolute position or relative position according to the target position and target speed specified from the ladder program.
	Origin determination	Origin search: Establishes the origin using the specified search method. Present position preset: Changes the present position to a specified position to establish the origin. Origin return: Returns the axis from any position to the established origin. Absolute encoder origin: Establishes the origin using a Servomotor that has an absolute encoder, without having to use an origin search.
	Jogging	Outputs pulses at a fixed speed in the forward rotation or reverse rotation direction.
	Interrupt feeding	Performs positioning by moving the axis a fixed amount when an external interrupt input is received while the axis is moving.
	Speed control	Performs speed control by sending a command to the Servo Drive speed loop.
	Torque control	Performs torque control by sending a command to the Servo Drive current loop.
	Stop functions	Deceleration stop: Decelerates the moving axis to a stop. Emergency stop: Positions the moving axis for the number of pulses remaining in the deviation counter and then stops the axis.
Auxiliary functions	Acceleration/ deceleration curves	Sets one of the following: a trapezoidal (linear) curve, an exponential curve, or an S-curve (moving average).
	Torque limit	Restricts the output torque during axis operation.
	Override	Multiplies the axis command speed by a specified ratio. Override: 0.01% to 327.67%
	Servo parameter transfer	Reads and writes the Servo Drive parameters from the ladder program in the CPU Unit.
	Monitoring function	Monitors the control status of the Servo Drive, such as the command coordinate positions, feedback position, current speed, and torque.
	Software limits	Limits software operation within the positioning range during position control.
	Backlash compensation	Compensates for the amount of play in the mechanical system according to a set value.
	Deviation counter reset	The position deviation in the Servo Drive’s deviation counter can be reset to 0 (unit version 1.3 or later).
External I/O	Position Control Unit	One MECHATROLINK-II interface port
External I/O	Servo Drive I/O	Forward/reverse rotation limit inputs, origin proximity inputs, external interrupt inputs 1 to 3 (can be used as external origin inputs)
Self-diagnostic functions		Watchdog, flash memory check, memory corruption check
Error detection functions		Overtravel, Servo Drive alarm detection, CPU error, MECHATROLINK communications error, Unit setting error

MECHATROLINK Specifications

Item	Specifications
Communications protocol	MECHATROLINK-II
Baud rate	10 Mbps
Maximum transmission distance	50 m *1
Minimum distance between stations	0.5 m
Transmission media	Shielded, twisted-pair cables
Maximum No. of stations	30 slave stations max. *2
Topology	Bus
Transfer cycle	250 μs to 8 ms
Communications method	Master-slave, totally synchronous
Encoding	Manchester encoding
Data length	17 bytes/32 bytes selectable *3

*1. This distance is the total length of the cable connected between devices. However, the maximum length depends on
the number of devices connected and whether Repeaters are used.
*2. Up to 16 devices can be connected to the CJ1W-NCF71(-MA), up to 2 devices can be connected to the CJ1W-NC271,
and up to 4 devices can be connected to the CJ1W-NC471.
*3. The PCU data length is fixed at 32 bytes.