Revolution Pi Connect 4

The RevPi Connect 4 is an industrial DIN-rail computer built on the Raspberry Pi Compute Module 4. It combines the openness of Raspberry Pi and Debian Linux with robust industrial hardware – including an on-board digital input and relay output – and can act as edge gateway, soft PLC, IIoT controller and HMI at the same time.

With the open-source edge agent thin-edge.io, the RevPi Connect 4 connects to Cumulocity in a few minutes: collect machine and sensor data, monitor device health, and manage software, configuration and logs remotely across your entire fleet.

Machine data collection and retrofit

Read data from PLCs, drives, sensors and energy meters via Modbus RTU (RS485), Modbus TCP or OPC UA and send it to Cumulocity – without touching the existing machine control.

Energy and utility monitoring:

Connect several meters on one RS485 bus and visualize consumption, peaks and alarms in Cumulocity.

Power-fail aware operation

Wire the power-good signal of a UPS to the on-board digital input: the device can shut down safely and raise an alarm in Cumulocity before data is lost.

Sensors, signals and control in one device

Switch a signal lamp or contactor via the on-board relay output, add RevPi digital, analog and relay modules to capture machine states, counters, 4–20 mA sensors or Pt100 temperatures, and run your control logic locally (e.g. as a soft PLC) while thin-edge.io forwards the relevant data to the cloud.

Edge analytics and local HMI

The quad-core Cortex-A72 CPU and 4K Micro-HDMI output leave room for local preprocessing, containers, dashboards or a machine-side HMI.

Remote service

Reduce on-site visits with remote access, remote log retrieval and software updates from Cumulocity.

Technical Data

• Broadcom BCM2711, quad-core Arm Cortex-A72 @ 1.5 GHz (Raspberry Pi CM4), passively cooled
• 2 GB RAM with 8 GB eMMC, or 4 GB / 8 GB RAM with 32 GB eMMC (LPDDR4)
• Hardware Interfaces
  • 2 × Gigabit Ethernet (RJ45)
  • 1 × RS485 (screw-type terminal)
  • 1 × digital input, 24 V DC per IEC 61131-2 (e.g. power-good signal of a UPS)
  • 1 × digital output, opto-decoupled solid-state relay, normally open, max. 30 V / 300 mA DC
  • (optional) WLAN 2.4/5 GHz, Bluetooth 5.0 (BLE) RP-SMA socket for external antenna
  • 2 × USB-A 3.2 Gen 1
  • 1 × Micro-HDMI 2.0a (4K)
  • 1 × Micro-USB (for flashing the eMMC image only)
  • 6 status LEDs, 5 of them freely programmable (RGB)
  •  RevPi I/O modules (digital, analog, relay) via PiBridge on the left and right side
• Security TPM 2.0 (Infineon OPTIGA™ SLB 9670), hardware watchdog
• Power supply 10.8 – 28.8 V DC (typ. 24 V), max. 20 W incl. USB load – typically well below 4 W without HDMI
• Standards EMC per IEC 61000-6-2 / IEC 61000-6-4, CE, UKCA, UL (File No. E494534)

 

How the Connection to Cumulocity Works

thin-edge.io is a free, open-source software agent. It runs directly on the RevPi and needs only few resources. Every program on the device can hand over data to it. For example, this can be a Python script, a Node-RED flow or a soft PLC.

• Data: send measurements, events and alarms
• Device management: check device health, restart the device and run shell commands
• Software: install, update and remove packages remotely
• Configuration and logs: fetch and change files from Cumulocity
• Child devices: show connected machines or meters as separate devices
• Remote access: open secure SSH or VNC sessions via Cumulocity Cloud Remote Access

Add Inputs, Outputs

The Connect 4 has inputs or outputs of its own but can even be equipped with expansion modules right next to it. They plug into the system bus on both sides. All values then appear in one shared process image.

• RevPi DI, RevPi DO and RevPi DIO: digital inputs and outputs for machine states, counters, lamps and valves
• RevPi AIO and RevPi MIO: analog inputs and outputs for sensors such as pressure, level or temperature
• RevPi RO: relay outputs for switching higher loads

Details

Module	Channels	Typical use
RevPi DI	16 digital inputs (24 V, EN 61131-2), counter/encoder up to 2 kHz	Machine states, counters, pulse meters
RevPi DO	16 digital outputs, up to 500 mA, PWM	Signal lamps, valves, contactors
RevPi DIO	14 digital inputs + 14 digital outputs	Mixed machine signals
RevPi AIO	Up to 4 voltage/current inputs (±10 V, 0/4–20 mA), 2 RTD inputs (Pt100/Pt1000), 2 analog outputs	Pressure, flow and level sensors, temperatures
RevPi MIO	8 analog inputs, 8 analog outputs (0–10 V), 4 digital I/Os incl. PWM, pulse and encoder	Mixed analog/digital applications
RevPi RO	4 relay contacts, max. 250 V AC / 30 V DC, 5 A	Switching higher loads and AC circuit

Fieldbus connectivity: The RevPi Connect 4 is not compatible with RevPi Gateway modules (PROFINET, EtherCAT, EtherNet/IP, PROFIBUS). If you need to connect to these networks, choose the RevPi Connect S with the same base hardware, or the RevPi Connect 5.

Note: Expansion modules have their own temperature ranges (e.g. most I/O modules up to +55 °C). The most restrictive module defines the range of the overall system.

 

Available Variants

Item no.	RAM	eMMC	WLAN/BT
100376	2 GB	8 GB	–
100377	2 GB	8 GB	✔
100378	4 GB	32 GB	–
100379	4 GB	32 GB	✔
100395	8 GB	32 GB	–
100380	8 GB	32 GB	✔

Is the RevPi Connect 4 the Right Device for You?

A great fit if you…

• install hardware in a control cabinet with a 24 V supply,
• need a digital input and a relay output on board – e.g. for a UPS signal or an alarm lamp – without extra modules,
• collect data via Modbus RTU/TCP, OPC UA or MQTT and from digital/analog signals,
• want full freedom of a standard Linux (Debian-based RevPi OS) for your own applications,
• plan to scale from a pilot to a fleet managed centrally in Cumulocity.

RevPi Connect 4 or RevPi Connect 5?

Choose the RevPi Connect 4 if you want on-board digital I/O with relay output, a lean entry variant (2 GB RAM / 8 GB eMMC) and very low typical power consumption.

Choose the RevPi Connect 5 if you need more computing power (Cortex-A76 @ 2.4 GHz), CAN / CAN FD interfaces, fieldbus gateways (PROFINET, EtherCAT, EtherNet/IP, PROFIBUS) or operation up to +60 °C.

Getting Started in 5 Steps

1. Choose your variant based on RAM, storage and wireless requirements (see table above), plus any I/O modules you need.
2. Install and power up: Mount the device on a DIN rail, connect 24 V DC and Ethernet. Configure attached RevPi modules with the PiCtory web tool.
3. Install thin-edge.io on the device:
   curl -fsSL https://thin-edge.io/install.sh | sh -s
4. Connect to your Cumulocity tenant:
   sudo tedge cert create --device-id <your-device-id>
sudo tedge config set c8y.url <your-tenant>.cumulocity.com
sudo tedge cert upload c8y --user <your-user>
sudo tedge connect c8y
   Onboarding options evolve – always check the current thin-edge.io documentation.
5. Send your first data:
   tedge mqtt pub te/device/main///m/environment '{"temperature": 21.3}'
   The device and its measurement now appear in Cumulocity Device Management.

Step-by-step guide: Revolution Pi tutorial: Cumulocity with thin-edge.io

Resources

• RevPi Connect 4 in the Revolution Pi shop
• Datasheet (PDF)
• Tutorial: Installing thin-edge.io and connecting to Cumulocity

Partner: Revolution Pi (by KUNBUS GmbH, Germany)

Device on Partner Website