Analog input module RESI-C4-A-8RTD-2GB

digitalEthernetRS-485

USE THE POWER OF THE Raspberry Pi® Compute Module 4 IN YOUR SOLUTIONS
RESI has used Raspberry Pi® products since Compute Module 3 and has deployed thousands of controllers in customer projects. The result is an industrial-grade IoT controller based on the Raspberry Pi® Compute Module 4.

WHAT IS DIFFERENT?
The Compute Module 4 board is mounted inside an industrial enclosure suitable for DIN-rail and wall installation. Available enclosure sizes: 4MU, 8MU and 12MU. C4 controllers fit standard control cabinets with a 45 mm front cutout. An onboard wide-range power supply (12–48 VDC) is included. An ARM® coprocessor has been added to handle serial RS485 and time-critical tasks. Coprocessor features: unique 96-bit serial number, 2 kB ferromagnetic RAM for persistent values, RTC with backup capacitor, status LEDs and DIP switches for software use. Standard Compute Module 4 features: 1×Micro HDMI, 1×Ethernet, 2×USB 2.0, RAM options 2/4/8 GB, 32 GB SD card with Linux OS.

BUILT-IN I/O!
Various versions with integrated I/Os are available. The ARM® coprocessor manages these I/Os internally so the software needs only one serial interface to control them. Example communication interfaces:

• /dev/ttyACM0 – ASCII text protocol
• /dev/ttyACM1 – MODBUS/RTU master protocol

Relay output versions are also available. Special IO options in the portfolio include LED strip output, temperature sensor inputs and blind/shade control.

UNIVERSAL ANALOG I/O (AIOX)
Available with 4, 8 or 16 channels. Each channel is individually configurable. Possible configurations:

• Analog input: 0/2–10 V or 0/4–20 mA
• Analog output: 0/2–10 V or 0/4–20 mA
• Resistance measurement: 0 to 1 MΩ
• RTD input: PT100, PT1000, NI100-DIN43760
• Digital input: 24 V DC or dry contact

HOW IS THE SERIAL INTERFACE USED?
The ARM® coprocessor maps the RS485 interface over USB to a serial device. Example:

• /dev/ttyACM2 – native serial (RS485 via USB), RS485 direction switching handled by the coprocessor

WHICH SOFTWARE?
Supplied with a standard Raspberry Pi Linux distribution. Supported and recommended open-source tools (examples):

• Node-RED, NodeJs
• Python, Java, JavaScript, C#, C++
• HTML, Scratch
• Databases: MariaDB, MongoDB, InfluxDB, PostgreSQL
• Visualization: Grafana, Apache
• Home Automation: OpenHAB, FHEM, Home Assistant, ioBroker
• Cloud/Communication: MQTT, HTTPS, Azure IoT, AWS web services
• VPN / Router: OpenWrt, OpenRouter, OpenVPN, WireGuard
• Multimedia: KODI
• PLC/Runtime: CODESYS

THIS VERSION?
Read actual temperature from up to 8 RTD sensors with the Compute Module 4 based IoT controller. Optional variants: second Ethernet interface or integrated LTE modem for remote communication. Sensor wiring: 2-, 3- or 4-wire. Supported sensor types: PT100, PT1000, NI100-DIN43760.

Technical specifications

• Product series: C4 (RPI Compute Module 4 based controllers)
• Article no. (reference): RESI-C4-A-8RTD-2GB
• Selected standard configuration on the page: 8x RTD inputs (2/3/4-wire)
• RAM option (selected on page): 2 GB (other options: 4 GB, 8 GB)
• Wide-range power supply: 12–48 V DC
• Enclosure: industrial enclosure for DIN-rail and wall mounting (4MU / 8MU / 12MU)
• ARM® coprocessor: RS485 management, 96-bit serial number, 2 kB ferromagnetic RAM, RTC with backup capacitor, status LEDs, DIP switches
• Standard Compute Module 4 ports: 1×Micro HDMI, 1×Ethernet, 2×USB 2.0
• Storage: 32 GB SD card with Linux OS (standard delivery)
• IO options: digital I/O, relay outputs, LED strip output, blind/shade control, temperature sensor inputs
• AIOX: 4 / 8 / 16 channels, configurable (analog I/O, mA/V, resistance, RTD, digital)
• Serial mapping: dev/ttyACM0 (ASCII), dev/ttyACM1 (MODBUS/RTU Master), dev/ttyACM2 (RS485 via USB)
• Max RTD channels in presented version: 8 RTD sensors
• Sensor wiring: 2-, 3- or 4-wire
• Supported sensor types: PT100, PT1000, NI100-DIN43760
• Price (excl. VAT) for configured variant: 524.30 EUR
• Note: Not all combinations are technically possible; check article and order numbers for the chosen configuration