Teltonika RUT200 — Digital I/O for Machine Status

The Goal

You have machines on the factory floor. You want to know if they are running or stopped. That data needs to reach your Unified Namespace via MQTT, where it drives dashboards, KPIs, and alerts.

The Teltonika RUT200 is an industrial cellular router with built-in digital inputs. It can detect a signal from the machine and publish it directly to your MQTT broker over 4G — no separate PLC, no Ethernet cable to the machine, no middleware. One device does both jobs.

What Counts as "Running"?

There is no universal definition. "Running" depends on your machine and your process. Common approaches:

Prerequisites

Hardware

• ☐ Teltonika RUT200 industrial cellular router (any RUT200xxxxx variant)
• ☐ Active SIM card with data plan (standard SIM size — or micro/nano with adapter)
• ☐ LTE antenna (included with RUT200, or external for better signal in metal enclosures)
• ☐ 9–30 VDC power supply (DIN rail PSU or bench supply — the RUT200 accepts a wide input range)
• ☐ Signal source — stack light tap, door sensor, relay contact, or dry contact output from the machine
• ☐ Wire — 0.5–1.5 mm² stranded, rated for the signal voltage (typically brown/blue or per your site standard)
• ☐ Optional: DIN rail mounting bracket (Teltonika PR5MEC23 or equivalent)

Tools

• ☐ Small flat-blade screwdriver (for the RUT200 I/O terminal block)
• ☐ Wire strippers
• ☐ Multimeter (for verifying signal voltage and continuity)
• ☐ Laptop with Ethernet port (for initial WebUI configuration)
• ☐ Ethernet cable (for initial setup only — not needed in production)

Software & Network

• ☐ MQTT broker accessible from the internet (or via VPN) — e.g. HiveMQ Cloud, EMQX Cloud, or self-hosted Mosquitto with TLS and port forwarding
• ☐ MQTT client for testing — VS Code MQTT extension, MQTT Explorer, or mosquitto_sub from the command line

RUT200 Hardware Overview

Terminal Layout

The RUT200 has two connectors relevant to this guide: a 2-pin power connector and a 4-pin I/O connector. Both use screw terminals accessible with a small flat-blade screwdriver.

# RUT200 Power Connector (2-pin)
Pin 1 — V+  (9–30 VDC positive)
Pin 2 — GND (power ground)

# RUT200 I/O Terminal Block (4-pin)
Pin 1 — DIN1  (Digital Input 1)
Pin 2 — DIN2  (Digital Input 2)
Pin 3 — DOUT1 (Digital Output 1 — open collector)
Pin 4 — GND   (ground reference for all I/O)

• DIN1 Primary digital input — this is what we will wire for machine running/stopped detection
• DIN2 Second digital input — available for a second signal (e.g. fault status, door sensor)
• DOUT1 Digital output (open collector) — can drive an indicator LED or relay remotely via MQTT; not used in this guide
• GND Shared ground reference for all I/O — must be connected to the signal source ground

Digital Input Specifications

How the Digital Inputs Work

The RUT200 digital inputs support two modes. Which one you use depends on what kind of signal your machine provides:

LED Indicators

Network Setup

Before wiring any I/O, get the RUT200 online and verify it can reach your MQTT broker. This section walks through the complete cellular setup from unboxing to verified internet connectivity.

Insert the SIM Card

Power off the RUT200 (or do this before first power-on). The SIM slot is on the bottom of the device, behind a small cover secured with a Phillips screw.

1. Remove the SIM slot cover screw and slide the cover off
2. Insert the SIM card with the gold contacts facing down and the notched corner oriented as shown on the slot label
3. Push the SIM card until it clicks into place
4. Replace the cover and screw

Power On and Access the WebUI

1. Connect 9–30 VDC to the power terminals (Pin 1 = V+, Pin 2 = GND)
2. Connect an Ethernet cable from your laptop to the RUT200 LAN port
3. Wait approximately 30 seconds for the device to boot
4. Open a browser and navigate to http://192.168.1.1
5. Log in with the default credentials — username: admin, password: printed on the device label (commonly admin01 on older units)

Configure the Cellular Connection

Navigate to Network → Mobile → General in the WebUI. Configure the following:

Click Save & Apply.

Verify Internet Connectivity

Navigate to System → Administration → Troubleshoot → Diagnostics. Run a ping test:

# Ping a public DNS server
Host: 8.8.8.8
Protocol: ICMP

# Then ping your MQTT broker
Host: your-broker.example.com
Protocol: ICMP

Firewall Configuration for MQTT

The RUT200 needs to initiate outbound connections to your MQTT broker. By default, outbound traffic is allowed on most cellular configurations. However, some corporate SIMs or carrier policies restrict outbound ports.

Navigate to Network → Firewall → Traffic Rules and verify that outbound traffic on your MQTT port is not blocked.

Remote Access (Optional)

Most cellular connections receive a dynamic IP behind carrier-grade NAT. This is fine for MQTT — the RUT200 initiates the outbound connection to your broker, so no inbound ports or static IP are needed.

If you need to remotely access the RUT200 WebUI for configuration changes:

• Teltonika RMS (Remote Management System) — the recommended approach. Teltonika's cloud platform provides secure remote WebUI access, firmware updates, and fleet management with no port forwarding required.
• VPN — configure WireGuard or OpenVPN on the RUT200 to connect to your corporate VPN. This gives the device a fixed internal IP.

Wiring Digital Inputs

There are two ways to wire a signal into the RUT200's digital inputs, depending on what kind of signal your machine provides. Read both methods, then follow the one that matches your signal source.

Method A: 24 V Active Signal Wiring

When the signal source provides voltage (typically 24 VDC), wire it directly to the digital input with a common ground:

  ┌─────────────────┐          ┌──────────────────┐
  │  SIGNAL SOURCE   │          │    RUT200 I/O     │
  │  (stack light,   │          │                   │
  │   PLC output,    │          │  Pin 1  DIN1  ◄───── signal wire (24V when active)
  │   contactor aux) │          │  Pin 2  DIN2      │
  │                  │          │  Pin 3  DOUT1     │
  │  Signal + ───────┼──────────┤  Pin 4  GND   ◄───── ground wire (0V reference)
  │  Signal GND ─────┼──────────┤                   │
  └─────────────────┘          └──────────────────┘

  When signal is ACTIVE:   DIN1 sees ~24V → Logic HIGH (1)
  When signal is INACTIVE: DIN1 sees ~0V  → Logic LOW  (0)

1. Identify the signal wire. Use a multimeter to confirm the voltage between the signal wire and ground when the machine is running. It should read 20–28 VDC (within the RUT200's 0–30 V range).
2. Run the signal wire from the signal source to the RUT200 I/O terminal block, Pin 1 (DIN1). Strip 6–8 mm of insulation and insert into the screw terminal. Tighten firmly.
3. Connect the ground. Run a wire from the signal source's ground (0 V / common) to the RUT200 I/O terminal block, Pin 4 (GND). This is critical — the RUT200 needs a common ground reference with the signal source.
4. Verify. With the machine running, measure the voltage between DIN1 and GND on the RUT200 terminals. You should see the signal voltage. With the machine stopped, it should read near 0 V.

Method B: Dry Contact Wiring

When the signal source is a potential-free contact (relay dry contact, reed switch, limit switch, door interlock), wire it between the digital input and ground. The RUT200 uses an internal pull-up resistor to detect whether the contact is open or closed.

  ┌─────────────────┐          ┌──────────────────┐
  │  DRY CONTACT     │          │    RUT200 I/O     │
  │  (relay, reed    │          │                   │
  │   switch, limit  │          │  Pin 1  DIN1  ◄───── wire A
  │   switch)        │          │  Pin 2  DIN2      │
  │                  │          │  Pin 3  DOUT1     │
  │  Terminal A ─────┼──────────┤  Pin 4  GND   ◄───── wire B
  │  Terminal B ─────┼──────────┤                   │
  └─────────────────┘          └──────────────────┘

  Contact CLOSED: DIN1 pulled to GND → Logic LOW  (0)
  Contact OPEN:   DIN1 pulled HIGH   → Logic HIGH (1)

  Note: Logic is INVERTED compared to Method A.
  Configure accordingly in the I/O settings (see next section).

1. Identify the contact terminals. A dry contact has two terminals (or three — COM, NO, NC). For "running = contact closed", use the COM and NO (normally open) terminals.
2. Wire terminal A to the RUT200 I/O terminal block, Pin 1 (DIN1).
3. Wire terminal B to the RUT200 I/O terminal block, Pin 4 (GND).
4. Verify. With the contact closed (machine running), measure continuity between DIN1 and GND — it should be near 0 ohms. With the contact open (machine stopped), it should be open circuit.

Stack Light Wiring (Most Common)

The most common signal source is a tap from the machine's stack light — specifically the green lamp wire, which is typically energised when the machine is in automatic cycle.

  Machine Control Panel
  ┌──────────────────────────────┐
  │                              │
  │  24VDC Bus ──┬── Green Lamp  │
  │              │               │
  │              │  ┌── tap ───────────────┐
  │              │  │            │          │
  │  0V Bus ─────┼──┼── Lamp GND│          │
  │              │  │            │          │
  └──────────────┼──┼────────────┘          │
                 │  │                       │
                 │  │    ┌──────────────┐   │
                 │  └───►│ DIN1 (Pin 1) │   │
                 │       │ DIN2 (Pin 2) │   │
                 │       │ DOUT1(Pin 3) │   │
                 └──────►│ GND  (Pin 4) │   │
                         └──────────────┘   │
                            RUT200 I/O      │
                                            │
  Green lamp ON  → DIN1 sees 24V → Running  │
  Green lamp OFF → DIN1 sees 0V  → Stopped

Configuring I/O

With the signal wired, configure the RUT200 to correctly read the digital input state.

Access the I/O Configuration

In the RUT200 WebUI, navigate to Services → Input/Output. You will see the status and configuration for DIN1, DIN2, and DOUT1.

Configure the Input Parameters

Click on DIN1 to open its configuration. Set the parameters based on your wiring method:

• Enabled Activates the input for reading and event generation
• Input type Set to Digital for binary on/off state detection
• Active state Determines which logic level means "active" (running). For Method A, HIGH = active because voltage present means running. For Method B, LOW = active because contact closed pulls the input to ground

Set Debounce

Debounce filters out rapid state changes caused by mechanical contact bounce in relays and switches. Without debounce, a single relay closure can generate multiple false transitions.

# Recommended debounce settings
Machine status (stack light, contactor): 200–500 ms
Door sensor / safety interlock:          100–200 ms
Solid-state signal (PLC output):         50 ms or off

For machine running/stopped detection, 300 ms is a safe default. This means the input must be stable for 300 ms before the RUT200 registers a state change.

Test the I/O State in the WebUI

Navigate to Services → Input/Output and observe the live status of DIN1.

1. Activate the signal (start the machine or manually apply the signal)
2. Confirm DIN1 shows state 1 (active / running)
3. Deactivate the signal (stop the machine or remove the signal)
4. Confirm DIN1 shows state 0 (inactive / stopped)

MQTT Configuration

The RUT200 has a built-in Data to Server feature that can publish I/O state changes directly via MQTT. No scripting, no middleware, no edge gateway. Configure it once and the device handles the rest.

Create the MQTT Connection

Navigate to Services → Data to Server. Click Add to create a new data sender instance. Configure the connection parameters:

• Client ID Must be unique across all devices connecting to the same broker. If two devices use the same Client ID, they will disconnect each other in a loop.
• TLS For self-signed certificates: navigate to Services → Data to Server → your instance → Security, and upload the CA certificate file (.crt or .pem).

Configure the Topic

Set the MQTT topic to follow the UNS Framework topic hierarchy. This ensures the data integrates cleanly with the fn-uns pipeline and any other consumers on the namespace.

# UNS Framework topic hierarchy
uns/v1/{enterprise}/{site}/{area}/{line}/{cell}/status/running

# Example for a CNC machine:
uns/v1/acme/factory-1/machining/line-a/cnc-001/status/running

• uns/v1 UNS Framework version prefix
• acme Your enterprise / company name
• factory-1 The physical site where the machine is located
• machining The area within the site (ISA-95 area level)
• line-a The production line
• cnc-001 The specific machine
• status/running The data point — machine running status

Configure the JSON Payload

In the Data to Server instance, configure the payload format. The RUT200 supports template variables that are replaced with live values at publish time.

{
  "timestamp": "%t",
  "running": %i1,
  "source": "din1",
  "device": "rut200-cnc-001"
}

• %t Replaced with the Unix timestamp at publish time
• %i1 Replaced with the current state of DIN1 — 1 for active (running), 0 for inactive (stopped)
• source Identifies which input this reading came from (useful when you add DIN2 later)
• device Identifies the physical device — helpful for troubleshooting when you have multiple RUT200s

Configure the Trigger

The Data to Server feature can publish on three triggers. Use a combination of On Change and Periodic for best results:

# Recommended trigger configuration
On Change:  Enabled
Periodic:   Enabled — every 60 seconds
On Boot:    Enabled

Enable and Save

1. Set the Data to Server instance to Enabled
2. Click Save & Apply
3. Navigate to Services → Data to Server and check the instance status

Testing

Run through each layer of the stack to confirm data flows end-to-end: cellular connectivity, I/O reading, and MQTT delivery.

Verify Cellular Connectivity

Navigate to Status → Network → Mobile and confirm:

• ☐ Connection state shows Connected
• ☐ Signal strength shows 3+ bars
• ☐ An IP address is assigned
• ☐ Data usage counters are incrementing

Verify I/O Reads Correctly

Navigate to Services → Input/Output and check the live state of DIN1:

1. Activate the signal (start machine or apply signal) → DIN1 should show 1
2. Deactivate the signal (stop machine or remove signal) → DIN1 should show 0

Verify MQTT Messages Arrive

On your laptop or server, subscribe to the topic and watch for messages:

# Using mosquitto_sub (command line)
mosquitto_sub \
  -h your-broker.example.com \
  -p 8883 \
  --cafile ca.crt \
  -u your-username \
  -P your-password \
  -t "uns/v1/acme/factory-1/machining/line-a/cnc-001/status/#" \
  -v

You should see messages like:

uns/v1/acme/factory-1/machining/line-a/cnc-001/status/running {"timestamp":"1711612800","running":1,"source":"din1","device":"rut200-cnc-001"}
uns/v1/acme/factory-1/machining/line-a/cnc-001/status/running {"timestamp":"1711612860","running":1,"source":"din1","device":"rut200-cnc-001"}
uns/v1/acme/factory-1/machining/line-a/cnc-001/status/running {"timestamp":"1711612875","running":0,"source":"din1","device":"rut200-cnc-001"}

• Line 1 Initial state or periodic heartbeat — machine is running
• Line 2 Periodic heartbeat 60 seconds later — still running, no change
• Line 3 On Change event — machine stopped (running changed from 1 to 0)

End-to-End State Change Test

With mosquitto_sub still running, perform a full cycle:

1. Start the machine → confirm a message arrives with "running":1
2. Wait 60 seconds → confirm a periodic heartbeat message arrives (still "running":1)
3. Stop the machine → confirm a message arrives with "running":0
4. Wait 60 seconds → confirm a heartbeat arrives (still "running":0)

Safety & Best Practice

Electrical Safety

Network Security

Installation Best Practice

Troubleshooting

Cellular Connection Issues

• ☐ No signal LEDs: Verify the SIM is seated properly and the antenna is connected. Try removing and reinserting the SIM (with power off).
• ☐ Signal but no data: Verify the APN is correct for your carrier. Check that the SIM's data plan is active and has remaining data allowance.
• ☐ SIM PIN required: If the SIM has PIN lock enabled, enter it in Network → Mobile → SIM. Or disable the PIN using a phone first.
• ☐ Carrier blocks ports: Some M2M SIMs restrict outbound ports. Try port 443 (MQTT over WebSocket/TLS) if 8883 is blocked. Contact your SIM provider to confirm allowed ports.
• ☐ Weak signal: Move the antenna to a higher position or outside a metal enclosure. Consider an external high-gain antenna for difficult RF environments.

Digital Input Not Reading

• ☐ Measure voltage: Use a multimeter to measure voltage between DIN1 (Pin 1) and GND (Pin 4) directly at the RUT200 terminals. For Method A, you should see signal voltage when active, ~0 V when inactive.
• ☐ Check ground wire: The most common cause of a non-reading input is a missing or disconnected ground wire. Verify continuity between the signal source ground and RUT200 Pin 4.
• ☐ Correct input? Verify you are wired to DIN1 (Pin 1), not DIN2 (Pin 2) or DOUT1 (Pin 3). The pin ordering is printed on the device label.
• ☐ Check threshold: If using a low-voltage signal (e.g. 5 V logic), verify the input threshold is set lower than the signal voltage in the I/O configuration.
• ☐ Dry contact continuity: For Method B, verify the contact actually closes with a multimeter on continuity mode. Some relay contacts have a COM, NO, and NC terminal — make sure you are using the correct pair.

MQTT Not Publishing

• ☐ Instance enabled? Navigate to Services → Data to Server and verify the instance shows "Enabled".
• ☐ Connection status: Check the instance status. "Disconnected" or "Error" indicates a broker connection problem — verify hostname, port, TLS, and credentials.
• ☐ TLS certificate: If using a self-signed broker certificate, verify the CA cert is uploaded correctly. Certificate mismatch is a silent failure — the connection simply will not establish.
• ☐ Broker firewall: Verify your MQTT broker allows inbound connections on port 8883 from the RUT200's cellular IP range (or from any IP if the broker is publicly accessible).
• ☐ Test with a public broker: Temporarily configure the RUT200 to publish to a public test broker (e.g. test.mosquitto.org port 1883) to isolate whether the issue is with your broker or the RUT200.

Messages Arrive But Data Is Wrong

• ☐ JSON template syntax: Check for missing commas, unmatched braces, or incorrect variable names in the payload template. Use the WebUI's format help to verify available template variables.
• ☐ Inverted logic: If "running":1 appears when the machine is stopped, your active state configuration is inverted. Change the Active State setting in the I/O configuration (see Configuring I/O).
• ☐ Wrong topic: If messages arrive on an unexpected topic, check the topic string in the Data to Server configuration for typos or missing path segments.
• ☐ Debounce too aggressive: If short machine stops are not captured, reduce the debounce timer. A 5-second debounce will hide any stop shorter than 5 seconds.

Lessons Learned

Next Steps