Editorial Technical Reference

Microcontroller/PLC Interface

This page explains how Microcontroller/PLC Interface is classified within Machinery and Equipment Manufacturing. Technical values and manufacturer relationships are research references; confirm the current specification and supplier evidence for each order.

Technical Definition & Core Assembly

Electronic interface component that enables communication and control between a microcontroller and a PLC within an industrial automation system.

View Full Specifications Explore Manufacturing Sources

Product Specifications

Technical details and manufacturing context for Microcontroller/PLC Interface

Definition
The Microcontroller/PLC Interface is a specialized hardware and software component designed to facilitate bidirectional data exchange, signal conversion, and protocol translation between a microcontroller unit (MCU) and a Programmable Logic Controller (PLC). As part of a Humidity Control Module, it serves as the critical communication bridge, allowing the microcontroller's sensor data processing and logic to command the PLC's actuator outputs for precise environmental regulation. The interface typically receives digital or analog signals from the microcontroller, such as processed humidity readings and setpoints, and converts them into formats compatible with the PLC's input modules, using standard industrial protocols like Modbus RTU/TCP. Conversely, it receives status and control feedback from the PLC, including valve positions and fan speeds, and relays it back to the microcontroller for system monitoring and closed-loop control logic execution. The interface supports a supply voltage of 24 V DC ±10% (per IEC 61131-2), with a current consumption of 0.2–0.5 A at 24 V DC no load. It provides 8–16 digital input channels (Type 1/3, 24 V DC) and 4–8 digital output channels (transistor, 0.5 A per channel), along with analog input resolution of 12–16 bits for 0–10 V or 0–20 mA signals. Communication is via Modbus RTU/TCP (other fieldbuses optional) with auto-detect baud rates from 9.6 to 115.2 kbps. The operating and storage temperature range is -40 to 85 °C (non-condensing), with relative humidity 5–95% (non-condensing). Ingress protection is IP20–IP65 depending on housing, and isolation voltage is 1500 V AC for 1 minute (input/output). Dimensions are 45×100×115 mm (W×H×D) for DIN rail mount, with a weight of 0.2–0.5 kg in a plastic housing. All listed values are reference ranges; verify model-specific specifications and standards with the legal manufacturer or supplier before procurement.
Working Principle
The interface operates by receiving digital or analog signals from the microcontroller, such as processed humidity readings and setpoints. It converts these signals into a format compatible with the PLC's input modules, using standard industrial protocols like Modbus RTU/TCP. Conversely, it receives status and control feedback from the PLC, such as valve positions and fan speeds, and relays it back to the microcontroller for system monitoring and closed-loop control logic execution. The interface ensures proper signal conditioning, electrical isolation, and protocol translation to maintain reliable communication between the two devices.
Common Materials
Printed Circuit Board (PCB), Integrated Circuits (ICs), Connectors
Technical Parameters
ParameterTypical rangeNotes & selection driver
Supply Voltage24 ±10% V DCWide-range input optionalIEC 61131-2
Current Consumption0.2–0.5 AAt 24 V DC, no load
Digital Inputs8–16 channelsType 1/3, 24 V DCIEC 61131-2
Digital Outputs4–8 channelsTransistor, 0.5 A per channelIEC 61131-2
Analog Input Resolution12–16 bit0–10 V, 0–20 mAIEC 61131-2
Communication ProtocolModbus RTU/TCPOther fieldbuses optionalIEC 61158
Baud Rate9.6–115.2 kbpsAuto-detect
Operating Temperature-40–85 °CExtended range optionalIEC 60068-2-1/2
Storage Temperature-40–85 °CNon-condensingIEC 60068-2-1/2
Relative Humidity5–95 %Non-condensingIEC 60068-2-78
Ingress ProtectionIP20–IP65Depends on housingIEC 60529
Isolation Voltage1500 V AC1 minute, input/outputIEC 61010-1
Dimensions (W×H×D)45×100×115 mmDIN rail mount
Weight0.2–0.5 kgPlastic housing

Ranges are indicative industry figures for RFQ preparation, not a supplier commitment. Confirm every value and standard with the legal manufacturer before ordering.

Components / BOM
  • Protocol Converter IC
    Translates communication protocols between microcontroller and PLC standards
    Material: semiconductor
  • Signal Conditioning Circuit
    Adjusts voltage levels and filters noise from input/output signals
    Material: PCB with passive components
  • Communication Port Part
    Physical connector for cabling to PLC and microcontroller
    Material: metal alloy
  • Electrical Isolation
    Breaks the galvanic path between the controller side and the PLC side so neither can damage the other.

Applied To / Applications

This component is essential for the following industrial systems and equipment:

Humidity Control Module
View system integration details

Industrial Ecosystem & Supply Chain Structure

Complementary Systems
Downstream Applications
Specialized Tooling

Application Fit & Sizing Matrix

Operational Limits
humidity: 5% to 95% non-condensing
temperature: -40°C to +85°C
voltage range: 3.3V to 24V DC
communication speed: Up to 1 Mbps
Media Compatibility
✓ Industrial control cabinets ✓ Factory automation environments ✓ Process control systems
Unsuitable: High-vibration or explosive atmospheres without additional protection
Sizing Data Required
  • Required communication protocol (e.g., Modbus, Profibus, Ethernet/IP)
  • Number of I/O points to be interfaced
  • Power supply voltage and current requirements

Reliability & Engineering Risk Analysis

Failure Mode & Root Cause
Communication Interruption
Cause: Electromagnetic interference (EMI) from nearby high-power equipment, poor grounding, or damaged communication cables disrupting data exchange between microcontroller and PLC.
I/O Module Failure
Cause: Overvoltage spikes from connected sensors/actuators, excessive current draw beyond rated capacity, or environmental contamination (dust, moisture) causing short circuits or component degradation.
Maintenance Indicators
  • Intermittent or complete loss of communication between devices indicated by error codes on PLC HMI or flashing status LEDs on interface modules.
  • Unresponsive or erratic behavior of connected field devices (e.g., sensors reading incorrectly, actuators moving unexpectedly) despite normal PLC program logic.
Engineering Tips
  • Implement proper shielding and segregation of communication cables from power lines, ensure robust grounding per IEEE/ISA standards, and use surge protectors on all I/O connections to prevent electrical damage.
  • Establish routine diagnostic checks via PLC software to monitor communication health (e.g., packet error rates, signal strength) and perform preventive cleaning of connectors/enclosures to avoid environmental contamination.

Indicative industry ranges for design and RFQ preparation. Confirm the exact figures and applicable standard with the manufacturer before specifying.

Compliance & Manufacturing Standards

Applicable Standards
IEC 61131-2:2017 (Programmable Controllers - Equipment Requirements and Tests) EN 61000-6-2:2019 (Electromagnetic Compatibility - Generic Standards - Immunity for Industrial Environments)

Quoted from the published standard.

Manufacturing Precision
  • PCB Trace Width: +/-0.05mm
  • Connector Pin Alignment: +/-0.1mm
Quality Inspection
  • Environmental Stress Screening (Temperature/Humidity Cycling)
  • Functional Safety Test (IEC 61508 SIL Verification)

Manufacturers of Microcontroller/PLC Interface

Manufacturer profiles associated with Microcontroller/PLC Interface.

Sourcing Microcontroller/PLC Interface from China?
Tell us your specification and target quantity — we will match it against manufacturer records and come back with the factories that fit.
Request manufacturers We manufacture this

Manufacturer listings support early research and capability understanding. They are not certification, ranking, or transaction guarantees.

Share this page

Compiled and source-reviewed by the CNFX editorial team. Each manufacturer above links to the page on that company's own website where the product is listed, with the date we checked it. How we source and review · Page last updated 6 September 2026

Technical documentation
Request current drawings, revision history, and a signed specification sheet.
Manufacturing capability
Verify equipment lists, process limits, capacity, and representative production evidence.
Inspection readiness
Confirm test methods, calibrated equipment, sampling plans, and traceable reports.
Supplier transparency
Check the legal entity, factory address, ownership, certifications, and direct contacts.

CNFX does not score or rank suppliers. Buyers must verify all claims and documents with the legal manufacturer before ordering.

Supply Chain Compatible Machinery & Devices

Heavy-Duty CNC Plasma Cutting Machine

The Heavy-Duty CNC Plasma Cutting Machine is a standalone industrial device designed for cutting conductive metals such as steel, stainless steel, aluminum, and copper alloys.

Explore Specs →
Automated Powder Coating System

Integrated industrial system for applying dry powder coatings to metal substrates.

Explore Specs →
Centrifugal Pump Impeller

The centrifugal pump impeller is a critical rotating component that converts mechanical energy from the motor into kinetic energy in fluid systems.

Explore Specs →
High-Precision CNC Laser Cutting Machine

Computer-controlled industrial machine using focused laser beams to cut sheet metal with micron-level accuracy.

Explore Specs →

Frequently Asked Questions

What is the primary function of this interface?

It enables bidirectional data exchange, signal conversion, and protocol translation between a microcontroller and a PLC, allowing the microcontroller to command PLC outputs and receive feedback for closed-loop control.

Which communication protocols are supported?

The interface supports Modbus RTU/TCP as standard, with other fieldbuses optional. The baud rate is auto-detected from 9.6 to 115.2 kbps.

What are the electrical specifications?

Supply voltage is 24 V DC ±10% (per IEC 61131-2), current consumption 0.2–0.5 A at 24 V DC no load. Digital inputs: 8–16 channels (Type 1/3, 24 V DC); digital outputs: 4–8 channels (transistor, 0.5 A per channel). Analog input resolution: 12–16 bits for 0–10 V or 0–20 mA.

What environmental conditions can it withstand?

Operating and storage temperature range is -40 to 85 °C (non-condensing), relative humidity 5–95% (non-condensing). Ingress protection is IP20–IP65 depending on housing. Isolation voltage is 1500 V AC for 1 minute (input/output).

Data basis: editorial classification, named public sources where available, and source-reviewed manufacturer records. See the editorial policy.

Data Basis

Editorial classification, named public sources where available, and source-reviewed manufacturer records.

Preliminary Technical Classification
This page supports structured research, RFQ preparation, and supplier evaluation. It does not replace buyer-led supplier qualification, standards review, or technical approval.
Buyer enquiry

Request manufacturing insight for Microcontroller/PLC Interface

Ask for use case, specification boundaries, supplier type, and RFQ preparation information for this product.

Where it goes
Straight to the CNFX editorial desk, and to the manufacturer if this product is linked to a claimed profile. Nothing is broadcast to a supplier list.
Your details stay here
We do not sell or rent enquiry data, and we do not add you to a mailing list. Used only to answer this request.
No commission, no middleman
CNFX is a directory. We take no cut of any order and never negotiate on a supplier's behalf.
What we don't claim
A listing is not an endorsement. Qualify every supplier and verify every figure yourself before ordering.

Your business information is used only to process this request.

Thank you! Your message has been sent. We'll respond within 1–3 business days.
Sorry, we couldn't send your message. Please try again, or email us at [email protected].

Need to Manufacture Microcontroller/PLC Interface?

Compare manufacturer profiles with relevant product and process capability.

Create Manufacturer Profile Contact Us
Previous Product
Z-axis Ram/Spindle
Last Product
Get QuotesChat