EtherStax® Series for High Channel-count Applications

EtherStax high-density I/O blocks are designed for high-reliability operation and process up to 96 I/O channels on a single, vertically-stackable unit. Each I/O block has redundant Modbus TCP/IP network and power ports to ensure dependable operation. Rugged, aluminum enclosures protect against shock and vibration. For OEM systems, or those that require specialized housings, a lower-cost open circuit board version without the enclosure is also available. Etherstax are ideal for a broad range of measurement and control applications.

Rugged, Industrial-Grade Design

Etherstax are designed for high-reliability operation. Units feature an extended operating temperature range, 3-way isolation and surge protection. The I/O circuitry has over-temperature, over-voltage, and over-current protection. Redundant communication paths and DC power help prevent downtime on critital applications. If network communication is lost, outputs fail safely and a relay provides local alarming or shutdown functions.

i2o® Peer-to-Peer Communication

Input channels on one unit can write directly to output channels on another unit without a host controller in between.

Stackable, High-Density I/O

A variety of models offer a mix of analog and discrete I/O interfaces with up to 96 channels on a single unit. Monitor sensors, control devices, or add local alarms. The units interlock for secure stacking that consumes little space when mounted on a surface or DIN rail.

EtherStax® Series for High Channel-count Applications
Made in The USA

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Key Features & Benefits

  • High-density industrial Ethernet I/O: Put hundreds of I/O channels in less panel space.
  • Stackable aluminum or open-board packaging: Choose industrial-strength or low-cost mounting.
  • Rugged, shock and vibration-resistant design: Mounts on machinery, DIN rail, wall, or flat surface.
  • Modbus TCP/UDP/IP or i2o peer-to-peer network: Reliable communication to host or between nodes.
  • Easy web configuration with copy function: Quickly set up units with any web browser.
  • Dual-port Ethernet hub or switch w/MDI/MDI-X: Get diagnostics, redundancy, and easy expansion.
  • Ready for STP, RSTP, other redundancy schemes: Supports dual-path communication via copper and fiber.
  • Local failsafe SPST 5A fault relay: Provides alarm/shutdown if network or power fails.
  • Surge suppression and 1500Vrms isolation: Protects power, relay, I/O, and each Ethernet Port.
  • Redundant DC power w/internal diode coupling: For “bump-less” transfer to back-up power.
  • Extended operating temperature of -40 to 70°C
  • Designed UL/cUL Class1 Div 2 ABCD
EtherStax Key Features & Benefits

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Network and I/O Configuration Screens

EtherStax Network and I/O Configuration Screen One

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EtherStax Network and I/O Configuration Screen Two

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Ideal for Remote I/O or Control Rooms

With a variety of I/O configurations and flexible signal ranges, EtherStax serves many industries.

End-user Industries:

  • Power generation & distribution
  • Water & wastewater
  • Oil & gas refining
  • Food, dairy, beverage
  • Chemical/petrochem
  • Metals processing
  • Pharmaceutical
  • Military & Aerospace

OEM Machinery

  • Engine & turbine controls
  • Packaging equipment
  • Semiconductor fabrication
  • Switch gear equipment
  • Boilers & furnaces
  • Material handling

System Integrators:

  • SCADA applications
  • Factory automation
  • Building & energy management
  • Specialty machinery

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Distributed I/O for Batch Processing

EtherStax I/O interfaces sensors, actuators, displays and other instruments to a PLC, DCS, or PC over your Ethernet network. Analog inputs monitor temperature, level, flow, pressure, voltage, current, and myriad process variables. Analog outputs control drives, pumps, valves, motors, and heaters, or write to displays and recorders. Discrete inputs detect open/close and change-of-state while discrete outputs perform on/off control.

SCADA and Remote I/O

In addition to all the functions already mentioned, EtherStax are ideal for supervisory control and data acquisition at remote sites. Units tolerate -40 to 75°C allowing outdoor mounting. Flexible, redundant power supports battery operation. Multi-media capability enables use of copper, fiber-optic, or wireless Ethernet networks to eliminate the high cost of leased lines.

Discrete Manufacturing

EtherStax models with high-density discrete I/O provide a cost-efficient solution for automated operations such as machining, assembly, and packaging. These compact units can mount on machinery without worry of electrical noise, high voltage surges, or vibration affecting performance. EtherStax have a high level of immunity and resistance to transient signals from solenoids, motors, and magnetic fields.

Ethernet-Enable your OEM Machinery

Make your machines Internet-ready with EtherStax and monitor operation from any PC with an Ethernet link. The rugged aluminum housing can bolt directly to your equipment. Alternatively, the openboard version can mount in a NEMA enclosure or inside your machine. Resistant to shock and vibration, EtherStax units provide dependable operation even on moving machinery.

EtherStax - Discrete I/O Modules

EtherStax – Discrete I/O Modules
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EtherStax - Analog I/O Modules

EtherStax – Analog I/O Modules
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EtherStax - Open Board OEM Versions

EtherStax – Open Board OEM Versions
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General Specifications

For information about specific units, please refer to the model data sheets or manuals.

Inputs and Outputs

See individual model data sheets for details.

Enclosure and Physical

Dimensions: 8.226 inches wide x 2.444 inches tall x 7.25 inches deep. Units stack together on 2.175 inch centers.

I/O Connectors: Plug-in terminal blocks rated for 15A/300V; AWG #12-24 stranded or solid copper wire.

Network Connectors: See Ethernet Interface

Enclosure Material: Extruded aluminum, 6063 T6 alloy, silver anodized finish.

Printed Circuit Boards: Military grade fire-retardent epoxy glass per IPC-4101/98.

Safety Approvals: UL/cUL Listed

Hazardous Locations: Class 1; Division 2; Groups A, B, C, and D


Operating Temperature: -40 to 70°C (-40 to 158°F)

Storage Temperature: -40 to +85°C (-40 to +185°F)

Relative Humidity: 5 to 95%, non-condensing.

Power Requirements (Unit Main): 18-36V DC. Redundant, diode-coupled terminals. See individual model data sheets for power specifications.

Isolation: I/O, power, relay, and Ethernet port-to-port. Peak: 1500V AC, ANSI/ISA-82.01-1988. Continuous: 250V AC, 354V DC

Installation Category: Designed for Pollution Degree 2 environment with an Installation Category II rating (over-voltage category).

Electromagnetic Interference Immunity (EMI): I/O have resistance to inadvertent state changes with interference from switching solenoids, commutator motors, and drill motors.

Electromagnetic Compatibility (EMC): Meets EN50082-1

Electrostatic Discharge (ESD) Immunity: Meets EN61000-4-2

Radiated Field Immunity (RFI): Meets EN61000-4-3 and ENV50204.

Electrical Fast Transient Immunity (EFT): Meets EN61000-4-4.

Conducted RF Immunity (CRFI): Meets EN61000-4-6.

Surge Immunity: Meets EN61000-4-5.

Emissions: Meets EN61000-6-4:2007.

Radiated Frequency Emissions: Meets CISPR16 Class A

Shock and Vibration Immunity: Rating for single surface-mount unit in enclosure. Mechanical Shock: 50g, 3ms, with 3 half-sine shock pulses in each direction along 3 axes (18 shocks), and 30g, 11ms, with 3 half-sine shock pulses in each direction along 3 axes (18 shocks), per IEC60068-2-27. Random Vibration: 5g sinusoidal & 5 grms random vibration 10-500Hz, in 3 axes at
2 hrs/axis per IEC60068-2-64 & IEC60068-2-6.

Ethernet Interface

Network Connector (Copper): 8-pin RJ-45 sockets for 10Base-T/100Base-TX connections. Wired MDI-X by default but includes automatic MDI/MDI-X crossing.

Network Connector (Fiber): Duplex SC-type, multi-mode transceiver for IEEE 802.3u 100Base-FX cable connections.

Protocol: Modbus TCP/IP or UDP/IP with integrated web-browser reconfiguration.

i2o Peer-to-Peer Communication: Supported on select models only. See individual model data sheets for details.

IP Address: Default mode static IP address is

Port: Up to 10 Modbus TCP/IP sockets supported. Uses port 502 (reserved for Modbus).

Transient Protection: Transient voltage suppressors are applied on all ports (power, I/O, Ethernet ports).

Data Rate: Switch mode: auto-sense 10Mbps or 100Mbps on copper connections, 100Mbps on fiber-optic connection. Hub/repeater mode: fixed at 100Mbps and auto-negotiation does not apply.

Duplex: Switch mode: auto-negotiated, full or half duplex. Hub/repeater mode: only half-duplex and auto-negotiation does not apply.

Compliance: IEEE 802.3, 802.3u, 802.3x.

Network Distance: Distance between two devices on an Ethernet network is generally limited to 100 meters using copper cable, and 2km using multi-mode fiber optic cable. Distance may be extended using hubs and switches.

Address: IP address can be preset by the user (static) and loaded from internal non-volatile memory, or it can be automatically acquired at startup via a network server using a BOOTP (Bootstrap Protocol) or DHCP (Dynamic Host Configuration Protocol). Includes default mode toggle switch to revert unit to a “known” fixed static IP address of, useful for trouble-shooting purposes.

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Using i2o technology, many BusWorks XTBusWorks 900EN, and EtherStax I/O modules have the ability to operate like a long-distance transmitter. Either reproduce your sensor inputs at Point A as 4-20mA control signals at Point B, or monitor a discrete device at one site by reproducing the level with a relay at another location.

Learn More: Acromag i2o® Peer-to-Peer Communication Technology

Diagram showing EtherStax with i2o Technology

Because We Know I/O

Because We Know I/O

Doing business with Acromag means you can count on receiving dependable value when using our products. We guarantee to meet or exceed published product performance specifications and offer you exceptional personal service with a real person within one business day.

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