Manufactured Flex RangeRefo-Flex VSD Reforming
A mobile, PLC-controlled reforming system that safely re-energises the DC-link capacitors in stored variable speed drives — bridging long-term storage and operational readiness.
Stored VSDs degrade when their DC-link capacitors sit unpowered, risking catastrophic failure or nuisance trips on start-up. Refo-Flex automatically steps through the correct DC voltage levels for the drive class, OEM-independent, so mothballed drives stay warranty-compliant and start-ready. Engineered and built by PPE Technologies.
Built around your stored drive assetsKeep mothballed drives start-ready
Refo-Flex helps preserve the condition of stored VSD assets by providing a controlled method of preparing them for future use. It supports a more reliable return to service after extended storage, helping protect equipment value and reduce uncertainty when drives are brought back into operation.
Protect stored drives
Unpowered VSDs degrade as their DC-link capacitors sit idle. Controlled reforming maintains capacitor health, avoiding catastrophic failure or nuisance trips on start-up.
Automated, OEM-independent
An integrated PLC/HMI steps through the correct DC voltage levels for the drive class — ABB or any major brand — with no manual resistor swapping or “watching the clock”.
Safe and site-ready
A rotating beacon and audible alarms flag live reforming, it runs off a standard 230 V supply, and heavy-duty wheels make it easy to move around site.
Typical project environmentsWhere Refo-Flex works
Refo-Flex is well suited to operations where stored or standby drives form an important part of maintenance and continuity planning. Its portable, controlled approach allows reforming to be carried out across different sites and operating environments wherever drive readiness needs to be maintained.
Mining & minerals
Vital for mothballed equipment and planned shutdowns.
Oil & gas
Ensuring drive reliability in remote, critical environments.
Utilities
Water, wastewater and power generation maintenance.
Warehousing
Keep spare drive inventory “flight-ready” at all times.
Technical overviewA closer look at drive readiness
Refo-Flex brings a controlled, repeatable approach to preparing stored VSDs for service after extended periods of inactivity. The technical overview alongside provides a clear picture of how the system is structured and how it supports a reliable reforming process before a drive is returned to operation.
Product category
Mobile, PLC-controlled DC-link capacitor reforming system for stored variable speed drives
Configuration
Portable wheeled enclosure; supports drive classes from 230 V up to 690 V; runs off a standard 230 V IEC (C14) supply — no special site power required
Protection & control
PLC-controlled reforming sequences with an intuitive HMI; automatic DC voltage stepping by drive class; rotating beacon and audible alarms for live reforming
Interfaces
OEM-independent — compatible with ABB and other major VSD brands
Manufacturing
Engineered and assembled by PPE Technologies; reforming aligns with OEM guidelines (e.g. ABB)
Project support
Commissioning and recommissioning support, with guidance on VSD storage and reforming schedules
Documentation
Operating information and supporting product documents
Product resourcesResources for maintaining drive readiness
Supporting information provides added context around the Refo-Flex reforming process and the role it plays in preserving stored VSD assets. The resource below offers a practical next layer of detail for understanding how the solution fits into long-term drive maintenance and storage planning.
Read More
DC-Link Capacitor Fundamentals
A DC-link capacitor is an energy-storage component located in the direct-current portion of a variable speed drive (VSD). It forms part of the electrical link between the drive’s input conversion stage and its output switching stage. When a VSD has remained unpowered, the condition of this capacitor is an important consideration when the stored apparatus is being prepared for a controlled return to service.
Reforming refers specifically to the controlled re-energising of the DC-link capacitors. It is a defined electrical process for the capacitor section of the VSD, rather than a general description of every check that may be required before the drive is operated.
Understanding Controlled Voltage Stepping
In a reforming sequence, the DC voltage is increased in controlled stages appropriate to the applicable drive class. This staged approach is distinct from unrestricted direct energisation: each stage provides part of the process through which the DC-link capacitor is re-energised under controlled conditions.
The applicable sequence depends on the relevant VSD and project requirements.
Scope of Capacitor Reforming
Reforming addresses the controlled re-energising of the VSD’s DC-link capacitors. By contrast, terms such as “start-ready” and “return to service” describe the intended readiness context for a stored drive; they do not, by themselves, confirm that every other drive subsystem or connected installation has been examined.
A complete return-to-service decision may involve requirements beyond capacitor reforming, depending on the apparatus, its installation, and the applicable project scope. Those requirements should be identified separately so that reforming is not treated as a substitute for installation checks, commissioning, operational testing, or acceptance testing where those activities are applicable.
Refo-Flex Flyer
A concise introduction to Refo-Flex, explaining its purpose and role in keeping stored VSDs ready for future operation.
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Discuss your VSD reforming requirement
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