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Product Description
The Mitsubishi FX3S-30MRES is a versatile, compact programmable controller for diverse automation applications, featuring 16 input points for signal monitoring and 14 relay outputs capable of handling 2A resistance or 80VA inductive loads (minimum 5VDC/2mA). It supports 24 VDC or 100-240 VAC input power, offers a fast 10ms input response with photocoupler insulation, mechanical output insulation, LED status indicators, and requires a 30 VDC external power supply.
Is Your Device Showing These Signs?
The Mitsubishi FX3S-30MRES PLC commonly experiences issues such as program corruption necessitating firmware reflashing, power supply failures leading to intermittent operation or complete shutdown, I/O module communication errors requiring bus termination checks and cable replacements, and overheating due to inadequate ventilation causing CPU faults. Resolving these problems involves verifying program integrity using GX Works software, replacing the power supply unit, inspecting the RS-485 communication network for proper termination and cable faults, and ensuring adequate airflow around the PLC to prevent thermal shutdowns. Addressing these issues restores optimal functionality and prevents future system failures.
Technical specifications
The Mitsubishi FX3S-30MRES is a compact programmable controller with 16 inputs, 14 relay outputs (2A/80VA), supports 24 VDC/100-240 VAC input power, features 10ms input response, photocoupler/mechanical insulation, LED indicators, and requires a 30 VDC external power supply.
Our Repair Process for the
FX3S-30MRES
Our repair process for the Mitsubishi FX3S-30MRES PLC begins with a thorough verification of program integrity using GX Works software to identify and correct any program corruption, often requiring a complete firmware reflash. Next, the power supply unit is replaced to address intermittent operation or complete shutdown issues. The RS-485 communication network is then meticulously inspected for proper termination and cable faults, with cable replacements performed as needed to resolve I/O module communication errors. Finally, we ensure adequate airflow around the PLC to prevent overheating, which can cause CPU faults and system failures; this may involve installing additional cooling solutions. These steps are crucial to restore optimal functionality and prevent future system failures.
Your Guarantee: Warranty & Lifetime Support
Your satisfaction is our top priority, and we confidently stand behind the quality of our repairs. That's why every repair service is covered by our comprehensive 24-month warranty. Furthermore, we offer lifetime phone support – if you have questions or need assistance related to our repair down the road, we're here to help. Our service commitment is straightforward: we guarantee our work, and if you're not satisfied, we will make it right. Learn More about our Repair process.
Comprehensive Repairs You Can Depend On
We take immense pride in the quality and reliability of our work. Our process goes beyond simply fixing the immediate problem. We perform a comprehensive inspection of your main board (or other equipment) and proactively replace components known to be failure-prone or showing signs of potential future failure. Before any item is returned, it undergoes rigorous functional testing to ensure it meets performance specifications and operates flawlessly. Visit our main Repair Services page to learn more.
Save Significantly
Our primary goal is to save you hundreds, or even thousands, of dollars compared to the cost of new equipment replacement. By repairing existing components, we provide an economical solution that is also eco-friendly. At Roc Industrial, our commitment to integrity and community drives our consistent growth and ensures you receive a reliable, cost-effective solution.


Please Note: Roc Industrial operates as an independent service provider and is not an authorized distributor for the manufacturers or brands mentioned. Consequently, the original manufacturer's warranty is not applicable to items repaired or sold by us. Roc Industrial provides its own 2-year warranty on all repair services performed.
Buying Options
To receive a quote within 2 hours, please provide us with the details of your requirements. Our team will promptly review your request and send you a custom offer.
Ships from Rochester, NY