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Product Description
The Allen-Bradley 20G1AND477JA0NNNNN PowerFlex 755 drive is a versatile 480VAC, 400HP, 477A general-purpose motor speed controller with multiple motor control modes, a dynamic brake transistor, built-in EtherNet/IP with Device Level Ring (DLR) for network resilience, comprehensive diagnostics, integrated EMC filtering, digital and analog I/O, open and closed loop speed regulation, safe speed monitor and safe torque-off, five option slots for flexible configuration, voltage and noise suppression, and selectable motor control algorithms for encoder or sensorless operation.
Is Your Device Showing These Signs?
The Allen Bradley 20G1AND477JA0NNNNN PowerFlex 755 AC drive commonly experiences issues such as IGBT failures, capacitor bank degradation leading to DC bus undervoltage faults, and encoder feedback problems causing erratic motor control. Communication errors on EtherNet/IP networks and control board failures are also frequent. Overcurrent trips, nuisance tripping due to improper parameter settings, and cooling fan malfunctions that result in overheating are addressed. Resolving these issues involves replacing faulty components, recalibrating drive parameters, and performing firmware upgrades to ensure optimal performance and prevent downtime.
Technical specifications
The Allen-Bradley 20G1AND477JA0NNNNN PowerFlex 755 is a 480VAC, 400HP, 477A general-purpose motor speed controller offering versatile motor control, built-in EtherNet/IP with DLR, extensive diagnostics, EMC filtering, I/O, speed regulation, safety features, option slots, and selectable motor control algorithms.
Our Repair Process for the
20G1AND477JA0NNNNN
Our repair process for the Allen Bradley 20G1AND477JA0NNNNN PowerFlex 755 AC drive begins with a comprehensive diagnostic evaluation to pinpoint the root cause of the failure, whether it be IGBT failures, capacitor bank degradation, encoder feedback problems, communication errors, control board failures, overcurrent trips, nuisance tripping, or cooling fan malfunctions. The identified faulty components are replaced, drive parameters are recalibrated to factory specifications or application-specific requirements, and firmware upgrades are performed to ensure optimal performance and prevent future downtime. Thorough testing under load conditions validates the repair, confirming proper operation and adherence to performance standards before the drive is returned.
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