EtherNet/IP standard I/O connection timeout

A Logix controller drops a standard EtherNet/IP I/O connection after RPI times a multiplier of at least 4, and never in less than 100 ms, while an OMRON NJ/NX controller defaults to 4 times the RPI with a floor of only 10 ms.

Values

Parameter	Value	Condition
Connection timeout	Multiplier x RPI¹	Implicit (I/O) messages. The controller firmware selects the multiplier.
Minimum timeout multiplier	4¹	Logix controllers
Minimum connection timeout	100 ms¹	Logix controllers. The firmware picks a multiplier large enough that the timeout is at least 100 ms.
Timeout at RPI 2 ms	128 ms¹	Rockwell Automation example; controller multiplier 64
Timeout at RPI 10 ms	160 ms¹	Rockwell Automation example; controller multiplier 16
Connection timeout, OMRON NJ/NX controllers	4, 8, 16, 32, 64, 128, 256 or 512 x RPI²	Tag data links on the NJ/NX built-in EtherNet/IP port. The default is 4 x RPI.
Minimum connection timeout, OMRON NJ/NX controllers	10 ms²	Connection settings in Sysmac Studio. At a 10 ms RPI and the default multiplier of 4, the connection times out after 40 ms, where the Logix example above waits 160 ms.
RPI range for I/O devices	Device dependent³	Valid ranges and defaults depend on the device; Logix Designer shows the valid range under the RPI field.
Where RPI limits are defined	Device EDS file⁴	ODVA recommends that device makers define minimum, maximum, and default RPI with a ParamN entry in the EDS, so tools do not pick a value beyond the device capacity.
RPI range, standard produced and consumed tags	0.196 to 536870.911 ms⁵	ControlLogix controllers
RPI range, standard produced and consumed tags	1 to 536870.911 ms⁵	CompactLogix controllers
Meaning of RPI	Producer send interval⁴	Producers send data packets at the RPI, and consumers listen for a packet at the same interval.
Transport for cyclic I/O	UDP⁶	EtherNet/IP runs CIP over standard Ethernet and TCP/IP and uses UDP for real time cyclic data.

Sources

EtherNet/IP Network Devices User Manual (ENET-UM006C-EN-P). Read Oct 5, 2026.
NJ/NX-series CPU Unit Built-in EtherNet/IP Port User's Manual (W506-E1-37). Read Oct 5, 2026.
Connection view parameters (Rockwell Automation add-on profile help). Read Oct 5, 2026.
EtherNet/IP Quick Start for Vendors Handbook (PUB00213R0). Read Oct 5, 2026.
Logix 5000 Controllers Produced and Consumed Tags (1756-PM011N-EN-P). Read Oct 5, 2026.
EtherNet/IP (ODVA). Read Oct 5, 2026.

About this page

Built from 6 sources: 2 protocol owners and alliances and 4 vendor documents. Researched and drafted with AI assistance, then reviewed and approved by Ben Rutter on Oct 5, 2026. How pages are made

First published: Oct 5, 2026
Last updated: Oct 5, 2026

Change history (1)

Oct 5, 2026 First published

Cite this page

Plain

Ben Rutter. "EtherNet/IP standard I/O connection timeout." OT Wireless, published October 5, 2026. https://otwireless.com/requirements/ethernet-ip-io/

APA 7

Rutter, B. (2026, October 5). EtherNet/IP standard I/O connection timeout. OT Wireless. https://otwireless.com/requirements/ethernet-ip-io/

BibTeX

@misc{rutter2026ethernetipio,
  author = {Rutter, Ben},
  title = {{EtherNet/IP standard I/O connection timeout}},
  year = {2026},
  howpublished = {\url{https://otwireless.com/requirements/ethernet-ip-io/}},
  organization = {OT Wireless},
}