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In overseas new energy project sites such as the Central Asian gobi, the Russian Far East, and African deserts, equipment faces enormous temperature differentials year-round: winter temperatures drop to -38°C, while summer surface temperatures rise to 55°C. Under such conditions, conventional box substations are highly prone to failures including low-temperature oil solidification, switch mechanism jamming, high-temperature overload tripping, and accelerated insulation aging—directly affecting continuous power generation of photovoltaic and wind power stations. Zhejiang Deyan Electric Co., Ltd. has optimized and upgraded its Chinese-style box substation for complex overseas operating conditions, achieving stable and continuous operation across a wide temperature range of -38°C to 55°C, providing reliable prefabricated power distribution solutions for global EPC contractors and new energy station customers.

When a distribution project is tendered, the visible part is the equipment list. What actually decides whether the station is energised on schedule is the work done before the equipment is shipped — scheme matching, structural design, integrated assembly, wiring and factory commissioning. In this article, "equipment" means one integrated package: high and low voltage switchgear cabinets, ring main units, and the compact stations built around them. Zhejiang Deyan Electric Co., Ltd. (DEYAN ELECTRIC) walks through the sequence.

Data centers choose dry-type transformers not because dry types are cheaper, but because oil-immersed transformers simply cannot be installed in most data centers — and they would never pass fire inspection. Dry-type transformers contain no flammable insulating liquid and carry no leakage risk, so they can be placed directly in a floor distribution room or even next to the equipment room. The real difficulty is not “dry type or oil type”, but how to calculate the capacity, how much temperature-rise margin to allow, how to deal with harmonics, and how the transformer and switchgear should work together.

Distribution rooms and compact substations are increasingly expected to run without a permanent operator on site. The question is no longer whether the equipment can do it, but what the station needs around it — sensing, an intelligent terminal, a communication channel and a back-end platform, all planned from the start. A station that is "smart" only on paper will still need daily visits.

In various distribution EPC general-contracting projects, the Ring Main Unit (RMU) acts as the core high-voltage component of package substations and box-type substations. The selection of its voltage level directly determines the stability, compliance and project cost of the whole power distribution solution, and it is also a key technical concern for EPC procurement engineers at the preliminary design stage. Many EPC general contractors raise a question at the early inquiry stage: What voltage-level ring main unit should be selected for distribution EPC projects?

In 10-35kV distribution projects, the ring main unit (RMU) and the box-type substation are frequently mentioned in the same design review. Because both are compact and both are factory-built, they are sometimes treated as competing options. They are not. The decision comes down to one question about the node you are planning: does this point need to step voltage down and distribute low-voltage power, or does it only need to switch, sectionalize and connect lines? Zhejiang Deyan Electric Co., Ltd. (DEYAN ELECTRIC), which manufactures both product lines, sets out the practical boundary below.