Drive Reliability, Explained
Practical articles on VFD fundamentals, troubleshooting, maintenance and the electrical environment — written by engineers, free of sales numbers. General guidance always defers to your site procedures and the equipment manual.
VFD Fundamentals
How drives work, why they age, and the vocabulary behind them.
Fault-code Reporting
Capture and report drive fault codes accurately across brands.
Troubleshooting Guides
Structured first steps when a drive misbehaves.
Preventive Maintenance
Planned care that catches risks before they become failures.
EMC & Power Quality
The electrical environment around the drive.
Application Notes
Service decisions in real industrial contexts.
Engineer Insights
Field notes from DUCHENG project work.
More from our published record
FAQ
Common questions about our scope, process and commitments.
What information should I include with a service request?+
The drive brand, exact model code, rated power and voltage, the fault code exactly as displayed, when the fault occurs, and the operating environment. Photos help more than anything: the nameplate straight-on, the fault display before any reset, and one wider shot of the installation.
Which brands and equipment do you service?+
DUCHENG is a multi-brand service team. VFDs are the primary focus — medium/high- and low-voltage — alongside servo drives, servo motors and HMIs. Whether a specific brand, model and voltage class can be serviced is confirmed per request, based on the equipment details you provide.
Do you repair on site or in a workshop?+
Both, and the triage decides: complex component-level faults on transportable units usually go to the workshop; large MV/HV systems and planned maintenance are handled on site. When you submit a request, an engineer assesses which path fits your equipment and situation.
How fast can you respond?+
Honestly: it depends. Actual scope, lead time and service commitments depend on equipment condition, parts availability, site access and the agreed service contract. Marking a request as an emergency helps us prioritize triage, and contracted customers have their response terms defined in their agreements.
Can aging MV drives really be serviced without shipping them out?+
In many cases, yes — that is what Blue Reconditioning is for. The work happens on site within a planned shutdown: condition assessment, deep cleaning, power-cell and component inspection, condition-based replacement, and controlled recommissioning. Feasibility for a specific system is confirmed by the condition assessment. DUCHENG has published a field record of exactly this work at a tire plant in Rayong, Thailand.
Do you supply spare parts?+
DUCHENG supports maintenance with spare-part identification, compatibility review, sourcing, pre-dispatch checks and coordinated replacement or return logistics. Availability, lead time and exchange terms depend on the specific brand, model and service agreement.
Is there a warranty on service work?+
Warranty terms are defined in the service contract for each scope of work — they depend on what is serviced, its condition and the agreed scope. We do not publish blanket warranty figures, because honest terms depend on the equipment in front of us.
How do I track a request I already submitted?+
Use the request code from your confirmation (it looks like DC-TH-XXXXXX) together with the email address you submitted, on the Track Service page. If you have lost the code, contact us and we will help you locate the request.
Not sure what the issue is?
Ask DCAI a question about VFDs — answers come from our knowledge base.
Drive fault, or a planned shutdown coming up?
Send the drive brand, model, fault code and nameplate photo — an engineer reviews every request.