Advantech ADAM-250PN Remote I/O

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Stop wiring everything into the cabinet.

In a classic setup, every sensor wire starts on the machine and ends up in the control cabinet. One sensor, one cable, all the way back. Multiply that by 50 or 200 sensors, and you get hours of wiring, kilos of copper, and one very unhappy person doing the troubleshooting. The Advantech ADAM-250PN flips that around. It’s a rugged IP-rated remote I/O module that you mount directly on the machine, and you run one network cable back instead. This article is your companion guide to the full video. Here you’ll find the hardware, wiring, diagnostics, the live-demo architecture, and every step to rebuild this on your own bench.

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The Full Video

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Why Classic Modular PLC I/O Holds You Back

Let’s be fair: modular PLC I/O has served us well for decades. But it comes with four limitations that don’t fit how modern factories want to work.

1. Locked inside the enclosure. The cards need a cabinet, a DIN rail and protection from the environment. They can’t live on the machine.
2. Separate cards for inputs and outputs. Need two more outputs? Buy another card. More part numbers, more spares on the shelf.
3. Talks only to your PLC. Your IT team, your dashboard, your cloud are locked out.
4. The expensive one. Want the data out anyway? Now you’re buying a gateway, an OPC UA license, extra hardware and somebody’s time to set it up.

None of this is broken. It just takes more time and money than it needs to.

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The New Approach: I/O on the Machine

Instead of every sensor wire running back to the cabinet, you mount a remote I/O unit directly on the machine, for example, one module per conveyor section. Power (24 VDC) and PROFINET are daisy-chained from module to module, and only one cable goes back to the PLC. Adding another conveyor? Bolt on another module and plug it into the chain.

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The Hardware

Here’s what matters on the module:

• 2 network ports (E1/E2) on top for PROFINET or Modbus TCP, so you can daisy-chain modules.
• 8 M12 ports (X1–X8), each carrying two channels: 16 channels in total.
• Every channel can be a digital input OR a digital output. You decide per channel in software. No separate input and output cards: one part number covers 16 DI, 8 DI + 8 DO, 10 DI + 6 DO, whatever your machine needs.
• Built-in 24 V sensor supply on every port: sensors are powered straight from the M12 cable, no extra PSU in the field.
• Two power groups: ports X1–X4 run on sensor power (Us, 1L core), ports X5–X8 on actuator power (Ua, 2L core) for higher loads.
• 2 power ports at the bottom.

Port	Channels	Power group
X1	DIO 0 / DIO 8	Us
X2	DIO 1 / DIO 9	Us
X3	DIO 2 / DIO 10	Us
X4	DIO 3 / DIO 11	Us
X5	DIO 4 / DIO 12	Ua
X6	DIO 5 / DIO 13	Ua
X7	DIO 6 / DIO 14	Ua
X8	DIO 7 / DIO 15	Ua

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Wiring the I/Os

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Wiring an input (Sink / NPN)

• M12 connection: most sensors today ship with an M12 connector, so you plug them straight in.
• IEC 61131-2 Type 3, sink (NPN) type inputs:
  • Logic 0: 0–5 V
  • Logic 1: 11–30 V
• On X1: pin 1 = Us (+24 V), pin 4 = CH0 (DIO 0), pin 2 = CH8 (DIO 8). One M12 cable can bring in two signals.
• Examples: switches, photoelectric sensors.

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Wiring an output (Source type)

• Source-type digital outputs: the module provides the 24 V to the load.
  • Us group: 0.5 A per channel
  • Ua group: 2 A per channel (solenoid valves, relays)
• On X2: pin 4 = DIO 1, pin 2 = DIO 9, pin 3 = Us GND (common to both outputs).
• Per-channel short-circuit and diagnostic protection: a shorted load costs you one channel, not the whole module.
• Examples: indicator lamps, tower lights, valves, relays.

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Built-in Diagnostics

The module tells you which channel failed and how, via LEDs and the network, so your PLC or dashboard can react.

• Digital inputs: wire-break detection
• Digital outputs: over-current, short to ground / short to power
• Power: over-voltage, under-voltage, over-current

You can also monitor and configure everything in the free Advantech I/O Module Utility: scan the network, find the module by IP, set each channel to DI or DO, watch live I/O states and read the diagnostics (for example Ch2: Wire-Break Fault).

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The Live Demo Architecture

The core idea of the demo: the PLC controls, the edge reads.

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Demo 1: PROFINET Setup in TIA Portal

1. Download the GSDML file for the ADAM-250PN from the Advantech product page (Technical downloads). The latest firmware is there too.
2. In TIA Portal: Options → Manage general station description files (GSD) → install the GSDML.
3. In the hardware catalog, search for ADAM, then drag the ADAM-250PN into the network view.
4. Assign it to the PLC: click Not assigned → PLC_1.PROFINET interface_1.
5. Set the IP address in the device properties, and check the PROFINET device name. It must match the name on the device; otherwise, the PLC can’t connect.
6. Open the device view → 16DIO module → General parameters and set the operating mode of each channel (DI or DO). Here you can also enable diagnostics and input delays.
7. Write your PLC tags and a small program, download, and go online.

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I/O addressing explained

The module occupies 2 input bytes and 2 output bytes (address 0–1). Channels 0–7 map to byte 0, channels 8–15 to byte 1: Demo tags as an example:

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Demo 2: Modbus TCP + Node-RED Dashboard

While the PLC is running, read the same module over Modbus TCP without stopping the PLC.

1. In the Advantech I/O Module Utility, check the Modbus tab. PROFINET and Modbus are both enabled by default. You can disable either if you like.
2. Read the coils in a Modbus simulator, or from your edge device with Node-RED.
3. In Node-RED, use a Modbus Read node: module IP, port 502, coil status, address 0, quantity 32.
4. Split the result with a small function node: coils 0–15 are inputs, 16–31 are outputs, and drive the dashboard LEDs.

The result: flip a switch on the bench and in TIA Portal, the utility and the Node-RED dashboard all update at the same moment. One module, two masters, no gateway.

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Demo 3: Node-RED → MQTT (Cloud)

The module doesn’t publish MQTT itself, so the edge device does it:

1. Node-RED polls the module (Modbus Read, see above).
2. A filter node (report by exception) only passes values that changed, so you don’t spam the broker.
3. A function node formats the payload and sets one topic per signal, e.g. lab/adam250pn/DI/0.
4. An MQTT out node publishes to HiveMQ Cloud (broker URL, username, password).
5. Open the HiveMQ web client or MQTT Explorer and watch true / false arrive live as you trigger a sensor.

From a sensor on the machine, through a PLC, to the cloud, all without touching the PLC code.

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Source Code & Resources

Quick-reference details from the demo:

• Modbus TCP port: 502
• Coils 0–15 = DI 0–15, coils 16–31 = DO 0–15 (Node-RED uses 0-based addresses)
• PLC: Siemens S7-1500, CPU 1516-3 PN/DP, TIA Portal
• Edge device: reComputer 2100 running Node-RED
• Broker: HiveMQ Cloud

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Where Does This Make Sense?

Anywhere the machine is big, rough, or spread out:

• Harbor tower cranes: the cabinet is 50 meters away from the sensors.
• Mining infrastructure: conveyors covered in dust and vibration.
• Oil & gas: pipelines spread across huge sites.
• Railway wayside equipment: out in the weather, far from any control room.

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The Verdict

The ADAM-250PN does three things really well: it gets the I/O out of the cabinet and onto the machine, it gives you 16 channels that can be input or output, and it supports PROFINET for the PLC and Modbus TCP for the edge at the same time. Add diagnostics that tell you exactly what broke, and it’s a strong option for any distributed machine or IIoT retrofit.

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Where to Buy

The ADAM-250PN is available online at IoTMart, Advantech’s official marketplace:

• Advantech IoT Mart
• Learn more: advantech.com/en-eu

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Key notes:

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Work With Me

I regularly test industrial automation and IIoT devices. If you’d like me to review your product or showcase it in my courses and YouTube channel: Email: rajvir@codeandcompile.com or drop me a message on LinkedIn