Customers must take great care when selecting a modular UPS because not all modular UPS systems are the same. There are two methods that can be used to parallel UPS: “Decentralised” parallel architecture (DPA) and “centralised” parallel architecture (CPA).
The majority of modular 3-phase UPS systems currently available use CPA technology. Because of the inherent weaknesses of CPA technology no manufacturer will boast that their products are CPA so the customer needs to find out such things for themselves by asking the right questions.
That is why we have released a white paper (“DPA vs CPA. How to avoid downgrading your UPS system availability when selecting a modular UPS”) on this topic on our website: