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ETH-IIRO-16 Family

Isolated Digital Input &Relay Output Ethernet Module


  • Ethernet 10/100 RJ45 connector for interfacing to CPU or network
  • 16 optically isolated inputs (3V to 31V)
  • 16 Form C electro-mechanical relays switch 1A
  • DHCP or static IP assignment
  • Internal, removable terminal board for easy wiring
  • PC/104 module size and mounting compatibility
  • Small (4" x 4"x 1.7") rugged industrial enclosure
  • DC Jack and screw terminals for external power
  • Designed, made, supported, and manufactured in the USA


  • Eight- and four- input/output versions
  • Input-only and relay-only versions
  • Economy “E” version without the screw terminal board
  • OEM (board only) version with PC/104 mounting holes and PCB footprint for added flexibility in embedded applications
  • Extended operating temperature (-40°C to +80°C)
  • Wide input (7VDC to 30VDC) external power
  • RoHS available
  • DIN rail mounting provision

The ETH-IIRO-16 Series (4, 8 and 16 channels) is an ideal solution for adding portable, easy-to-install, isolated input and relay output digital I/O capabilities to any Ethernet network. It is excellent for controlling external relays, driving indicator lights, fuel pumps, high voltage control and more. Typical industries are Automotive, Industrial, and Factory and Home automation.

This unit features 16 Form C (SPDT) electromechanical relays and 16 optically isolated digital inputs. The isolated, non-polarized inputs may be driven by either DC sources of 3-31 V (or higher by special order) or AC sources at frequencies of 40 Hz to 10KHZ. Optically isolating the digital inputs from each other and from the computer, assures smooth, error-free data transmission in noisy, real-world environments.

The input channels are accessed via a 34-pin IDC type vertical header. The fully protected outputs are de-energized at power-up to prevent an unintended control output signal. Data to the Form C relays are latched and are available via a 50-pin IDC type vertical header. To simplify field wiring connections, the ETH-IIRO-16 family includes an internal, removable termination board (ETH-STB-84), that mounts directly to the headers.

The ETH-IIRO-16 is designed to be used in rugged industrial environments but is small enough to fit nicely onto any desk or testing station. Its board is PC/104 sized (3.550 by 3.775 inches) and ships inside a steel powder-coated enclosure with an anti-skid bottom.

The ETH-IIRO-16 has a DC Jack and screw terminals to connect the required external power. This power can be provided by our PWR-ACDC-5V, your +5Vdc regulated power supply, or by ordering the –WI option where you provide from 7 VDC to 30 VDC.


The OEM (board only) version is perfect for a variety of embedded applications. What makes the OEM option unique is that its PCB size and mounting holes match the PC/104 form factor (without the bus connections). The board can be added to any PC/104 type stack by connecting it to an available 10/100 base T port typically available on embedded CPU form factors such as EPIC, and PC/104. It can also be installed using standoffs inside other enclosures or systems.


  • Industrial Automation
  • Embedded OEM
  • Portable DAQ
  • Laboratory
  • Home Automation
  • Kiosks


Because of Ethernet’s ubiquitous nature these boards are supported for use in all operating systems -- including Windows, Linux, Unix, iOS, Android, -- even Raspberry PI, etc. The software package includes free Linux and Windows software with sample programs and source code in C# and Delphi for Windows. Also provided is a graphical setup program in Windows and extensive Ethernet-packet level API documentation. Third party application support includes a Windows standard DLL API usable from most popular application programs. Embedded OS support includes Windows Embedded Standard, and all applications, operating systems, and PLCs and all other devices capable of TCP/IP communication.

Special Order

Please contact ACCES with your precise requirement. Examples of special orders are conformal coating, custom software or product labeling, and more. We will work with you to provide exactly what is required.


The ETH-IIRO-16 is available with optional cable assemblies, screw terminal boards, and a DIN rail mounting provision.

Available Reference Manuals

Available Software Downloads

Available Datasheets

Drivers and Downloads

Full list of available Downloads: Software Packages, Drivers, Manuals, and other documents

Custom Software

ACCES also offers Custom Software Services for our products. Our prices are unbelievably low, often as inexpensive as free! If you need something tweaked to support your needs, or an entire enterprise application developed from scratch, it is definitely worth your time to inquire with us, first.

Further information about available ACCES Software:

Redistributing Windows Drivers
A list of ACCES drivers and the files that compose them under different versions of Windows, so you can easily redistribute ACCES cards and drivers.


Isolated Inputs

  • Channels: 4, 8, or 16
  • Voltage: 3 to 31VDC or AC RMS (40 to 1000Hz)
  • Isolation: 500V channel-to-ground and channel-to-channel (see manual)
  • Response Times:
    • Filtered: 4.7ms rise and fall
    • Non-Filtered: 10µs rise; 30µs fall

Relay Outputs

  • Channels: 4, 8, or 16
  • Type: SPDT Form C
  • Contact Type: Single crossbar; Ag with Au clad
  • AC Load: 0.5A at 125VAC (62.5 VA max)
  • DC Load: 1A at 244VCDC (30W max)
  • Switching Voltage:125 VAC, 60VDC max
  • Switching Current: 1A max
  • Contact Resistance: 100mω max
  • Contact Life: 5 million operations min
  • Operating Time: 5msec max
  • Release Time: 5msex max

Bus Type

  • Ethernet 10/100 Base T, Auto-detecting, 1.5kV Isolation


  • Operating Temperature Range: 0°C to 70°C (Optional -40°C to +80°C)
  • Storage Temperature Range: -40°C to +85°C
  • Humidity: 5%-90%, non-condensing


  • Board Dimension: 3.550 x 3.775 inches
  • Box Dimension: 4.00 x 4.00 x 1.7 inches
  • Connectors:
    • Isolated Inputs: Dual row 0.1” 34-pin
    • Relay Outputs: Dual row 0.1" 50-pin
    • DC power jack: 2.0mm + center post
    • Screw terminals: Available via enclosure cutout


  • External AC/DC 5V regulated power is required
  • 5V @ 300mA plus 30mA per energized relay; 5V @ 780mA with all relays on, typical
Ordering Guide
ModelIsolated InputsForm C Relay Outputs

PWR-ACDC-5VExternal Regulated 5VDC Power Supply
MP104-DINDIN-rail mounting provision $19
Model Options (call for pricing)
-OEMBoard only version, (no enclosure or terminal board)
-TExtended operating temperature (-40°C to +80°C)
-WIWide Input External Power (7 to 30 VDC)
-RoHSRoHS compliant version
Acquisition, Control, Communication: Engineering and Systems