Industrial Automation

CJ1W-EIP21S

CJ-series EtherNet/IP Unit

CJ1W-EIP21S

EtherNet/IP unit with tag data link capacity of 180,000 words or more

last update: April 1, 2025

EtherNet/IP Units Specifications

Item		Specifications
Model number		CJ1W-EIP21S
Type		100Base-TX *1
Applicable PLCs		NJ-series, CJ (CJ1, CJ2) series, and CP1H *2
Unit classification		CJ-series CPU Bus Unit
Mounting location		CPU Rack or Expansion Rack
Number of Units that can be mounted *2		NJ-series System: 4 max. (including Expansion Racks) CJ series System: 8 max. (including Expansion Racks) *3 CP1H System: 2 max.
CPU Unit words used	Allocated CIO Area words (CPU Bus Unit words)	25 words/Unit (one unit number’s words)
	Allocated CIO Area words (CPU Bus Unit words)	These words contain control bits and flags, the target node PLC’s operating and error information, Unit status, communications status, registered/normal target node information, and FINS/TCP connection status.
	Allocated DM Area words (CPU Bus Unit words)	100 words/Unit (one unit number’s words)
	Allocated DM Area words (CPU Bus Unit words)	These words contain the IP address display/setting area.
	User-set area	Any usable data area words
	User-set area	Target node PLC’s operating and error information, and registered/normal target node information
	CPU Bus Unit System Setup	Not used.
Non-volatile memory within EtherNet/IP Unit (See note.)		The following settings are stored in the EtherNet/IP Unit’s non-volatile memory. Note: Unlike the regular Ethernet Units, the CPU Bus Unit Setup Area in the CPU Unit is not used for these settings. 1. Unit Setup (communications settings for the EtherNet/IP Unit, such as the IP address, DNS server settings, host name, baud rate, FINS/UDP settings, and FINS/TCP settings) 2. Tag data link settings (device parameters) 3. User authentication settings 4. Operation log
Transfer specifi- cations	Media access method	CSMA/CD
	Modulation method	Baseband
	Transmission paths	Star form
	Baud rate	100 Mbit/s (100Base-TX)
	Transmission media	Shielded twisted-pair (STP) cable Categories: 100 Ω at 5, 5e
	Transmission distance	100 m (distance between hub and node)
	Number of cascade connections	There is no limitation when a switching hub is used.
Current consumption (Unit)		650 mA max. at 5 V DC
Weight		91 g max.
Dimensions		31 × 90 × 65 mm (W × H × D)
Other general specifications		Other specifications conform to the general specifications of the CJ-series.

*1. If tag data links are being used, use 100Base-TX. Otherwise, 10Base-T can be used, but this is not recommended.
*2. For the CJ1W-EIP21S, the following CPU Units are supported.
NJ[]01-[][][][], CJ2H-CPU[][], CJ2H-CPU[][]-EIP, CJ2M-CPU[][], CJ1G-CPU4[]P, CP1H-X40D[]-[], CP1H-XA40D[]-[], CP1H-Y20DT-D EtherNet/IP Unit with unit version 1.0 or later (Lot number 241001[] or later) is required to connect CJ1W-EIP21S to NJ-series CPU Unit. Use NJ-series CPU Unit with version 1.67 or later and Sysmac Studio with version 1.60 or later.
*3. Up to seven EtherNet/IP Units can be connected to a CJ2H-CPU6[]-EIP. Up to two EtherNet/IP Units can be connected to a CJ2M CPU Unit.

Communications Specifications

Item			Specifications
Item			NJ	CJ2	CJ1
CIP service	Tag data links (Cyclic communi- cations)	Number of connections	256
		Packet interval (refresh cycle)	0.5 to 10,000 ms (in 0.5-ms units) Can be set independently for each connection. (Data is refreshed over the network at the preset interval and does not depend on the number of nodes.)
		Allowed communications bandwidth per Unit	6,000 to 12,000 pps *1
		Number of tag sets	256
		Tag types	CIO Area, DM Area, EM Area, Holding Area, Work Area, and network symbols *2
		Number of tags per connection (= 1 tag set)	8 (7 tags when the tag set contains the controller status)
		Maximum link data size per node (total size of all tags)	184,832 words
		Maximum data size per connection	504 bytes (252 words) or 1444 bytes (722 words) *3 Data synchronicity is maintained within each connection.
		Number of registrable tag sets	256 (1 connection = 1 tag set)
		Maximum size of 1 tag set	722 words (The controller status uses 1 word when the tag set contains the PLC status.)
		Maximum number of tags that can be refreshed per CPU Unit cycle *5	Output/Transmission (CPU to EtherNet/IP0) : 256 Input/Reception (EtherNet/IP to CPU) : 256		Output/Transmission (CPU to EtherNet/IP): 19 Input/Reception (EtherNet/IP to CPU): 20 *5
		Data that can be refreshed per CPU Unit cycle 5 The layout of the allocated CIO Area words is the defauly. 7	Output/Transmission (CPU to EtherNet/IP): 6,432 words Input/Reception (EtherNet/IP to CPU): 6,432 words		Output/Transmission (CPU to EtherNet/IP): 7,469 words Input/Reception (EtherNet/IP to CPU): 7,469 words
		Changing tag data link parameters during operation	Supported *7
		Multicast packet filter function *9	Supported
	Explicit messaging	Class 3 (connected)	Number of connections: 128
		UCMM (unconnected)	Number of clients that can communicate at one time: 32 max. Number of servers that can communicate at one time: 32 max.
		*CIP routing 10**	Supported CJ1W-EIP21/EIP21S, CS1W-EIP21/EIP21S, NJ-501-[][][][], NJ-301-[][][][], CJ2H-CPU[][]-EIP, CJ2M-CPU3[]
*FINS service 11**		FINS/UDP	Not supported	Supported
*FINS service 11**		FINS/TCP	Not supported	16 connections max.
SNMP		Agent	SNMPv1, SNMPv2c, SNMP trap
SNMP		MIB	MIB-II
EtherNet/IP conformance test			CT17
Ethernet interface			10BASE-T or 100BASE-TX Auto Negotiation or fixed settings

*1. In this case, pps means "packets per second" and indicates the number of packets that can be processed in one second.
*2. Network symbols can be used for the following CPU Units.
NJ501-[][][][]/NJ301-[][][][]/CJ2H-CPU6[]-EIP/CJ2M-CPU3[]/CJ2H-CPU6[] withe unit version 1.6 or later/CJ2M-CPU1[] with unit version 2.2 or later *3. To use 505 to 1,444 bytes as the data size, the system must support the Large Forward Open standard (an optional CIP specification). The CS/CJ-series Units support this standard, but before connecting to nodes of other companies, confirm that those devices also support it.
*4. If the maximum data size is exceeded, the data refreshing with the CPU Unit will extend over two or more cycles.
*5. If status layout is set to user settings, the maximum number of tags is as follows.

Output/Transmission	Input/ Reception
18	18

*6. The table below shows value when the layout type is User defined.

		When connected to CJ1 CPU Unit	When connected to CJ2 CPU Unit
Data (words) that can be refleshed per CPU Unit cycle	Output/Transmission	7321	6172
Data (words) that can be refleshed per CPU Unit cycle	Input/Reception	7385	6236

*7. If parameters are changed in the EtherNet/IP Unit, however, the EtherNet/IP Unit will be restarted. When other nodes are communicating with the affected node, the communications will temporarily time out and automatically recover later.
*8. Because the EtherNet/IP Unit is equipped with an IGMP client, unnecessary multicast packets can be filtered by using a switching hub that supports IGMP snooping.
*9. EtherNet/IP Unit with unit version 1.0 or later (Lot number 241001[] or later) is required to connect CJ1W-EIP21S to NJ-series CPU Unit.
Use NJ-series CPU Unit with version 1.67 or later and Sysmac Studio with version 1.60 or later.
*10. The EtherNet/IP Unit uses the TCP/UDP port numbers shown in the following table.

Service	Protocol		Port number		Remarks
Service	CJ1/CJ2	NJ	CJ1/CJ2	NJ	CJ1/CJ2	NJ
Tag data links	UDP		2222		The port number is fixed.
Class3, UCMM	TCP/UDP		44818
DNS	UDP		53
BOOTP client	---	UDP	---	68
Secure Comm	TCP	---	443	---	The port number is fixed.
FINS/UDP service	UDP	---	9600	---	Port numbers in the Unit Setup can be changed with the CX-Programmer	Port numbers in the Unit Setup can be changed with the Sysmac Studio.
FINS/TCP service	TCP	---	9600	---
FTP	TCP		20, 21
SNTP	UDP		123
SNMP	UDP		161
SNMP trap	UDP		162

Unit Versions and Software Versions

The following versions of the Sysmac Studio, CX-Programmer and Network Configurator are required to set EtherNet/IP Units.
Yes:Supported, ---:Not supported

CJ1W-EIP21S	*Sysmac Studio 1**		*CX-Programmer 2**		Network Configurator for EtherNet/IP		EIP21S User Management Tool
CJ1W-EIP21S	Ver.1.59 or lower	Ver.1.60 or higher	Ver.9.80 or lower	Ver.9.81 or higher	Ver.3.72 or lower	Ver.3.74a or higher	Ver.1.00 or higher
Ver.1.0	---	Yes *3	---	Yes	---	Yes	Yes

*1. Available only when connecting with NJ-series CPU Units.<br>

*2. Available only when connecting with CJ1/CJ2-series CPU Units.<br>

*3. Supported by unit version 1.0 or later (Lot number 241001[] or later).

Network Configurator Requirements

The Network Configurator is a software package designed for building, setting, and controlling a multi-vendor EtherNet/IP Network using OMRON's EtherNet/IP. It is included in CX-One version 3.0. The Network Configurator provides the following functions for building, setting, and controlling EtherNet/IP.

Item		Specification
System Requirements		Refer to the CX-One Catalog (Cat. No. R134), visit your local OMRON website.
Network connection method		CS1/CJ1	CJ2	NJ
	Serial interface	CPU Unit's Peripheral or RS-232C port	CPU Unit's USB or RS-232C port	CPU Unit's USB port
	Ethernet interface	EtherNet/IP Unit's Ethernet port	CPU Unit’s Ethernet port EtherNet/IP Unit’s Ethernet port
Location on Network		A single node address is used (only when directly connected to EtherNet/IP).
Number of Units that can be connected to Network		A single Network Configurator per Network (More than one Configurator cannot be used in the same system.)
Main functions	Network control functions	• The Network configuration can be created and edited regardless of whether the Network Configurator is online or offline. • The Network configuration can be read from a file or the network.
Main functions	Configuration functions	The EDS files used by the Network Configurator can be installed and deleted.
Supported file formats		Configurator network configuration files (.ncf) Configuration files (.ncf) created using the Network Configurator for EtherNet/IP (version 2) can be imported by selecting External Data - Import from the File Menu.

last update: April 1, 2025

Product Category

Automation Systems
- Programmable Controllers
  - CJ1
    - CPU Bus Units
      - CJ1W-ECT21
      - CJ1W-NC[]81 / []82
      - CJ1W-SPU01-V2
      - CJ1W-NC[]71
      - CJ1W-SCU
      - CJ1W-CLK
      - CJ1W-FLN22
      - CJ1W-DRM21
      - CJ1W-EIP21S
      - CJ1W-PNT21
      - CJ1W-PRM21
      - CJ1W-PRT21

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