Schneider Electric studies 800 VDC data centre arc flash

Schneider Electric has published an analysis of how to assess and manage arc flash risk in 800 VDC power architectures for data centres. It examines two representative 800 VDC designs used in AI-focused facilities.

The study addresses a gap in safety guidance as operators adopt higher-voltage power systems to support denser computing racks. No industry-wide standard currently exists for managing electrical hazards in converter-fed 800 VDC systems.

The report offers one of the first practical assessments of arc flash behaviour at both rack and facility level in 800 VDC data centre environments. Based on deployment scenarios shaped by design patterns used by hyperscale operators, it compares two emerging architectures with different configurations.

The findings show that arc flash outcomes vary sharply depending on system architecture, capacitor placement and fault-clearing speed. Even under conservative assumptions dominated by capacitor discharge, arc flash risk in 800 VDC systems can be managed and is often comparable with that of typical AC systems.

Safety modelling

Schneider Electric used simulation methods, advanced software and digital twin models to test fault scenarios and assess protection strategies. These tools provided a more accurate picture of arc flash risk than simplified approaches, which can overstate the danger in capacitor-dominated DC systems.

The work evaluated standards-based methods alongside transient simulation and broader system-level modelling. In 800 VDC systems, the first milliseconds of an arc flash event are heavily shaped by capacitor discharge, making time-dependent analysis important when engineers assess incident energy and protection requirements.

One case study examined a rack-level sidecar, or power rack, design. Under conservative assumptions, incident energy remained well below the referenced 1.2 cal/cm2 personal protective equipment threshold even without protection devices.

A second case study examined a centralised facility-level architecture. In that configuration, the analysis showed the potential for slightly higher incident energy than in rack-level designs under a conservative setup with no overcurrent protection.

Fault location also matters. Modelling of faults upstream and downstream of reverse-blocking diodes found that these positions affected back-feed, peak current and the resulting arc flash outcome.

When standard protection devices limited fault contribution over time, arc flash energy fell to levels suited to the working environment and broadly aligned with common AC architectures. The analysis concludes that design and protection choices, rather than DC distribution alone, are central to managing risk.

The work comes as 800 VDC power distribution gains attention as a way to support 400 kW IT racks and larger systems in AI data centres. Higher rack densities are pushing operators to reconsider power infrastructure while also raising questions about fault behaviour, protection coordination and safe maintenance procedures.

Manish Kumar, EVP of Secure Power & Data Centres at Schneider Electric, outlined the company's view of that shift.

"800 VDC power distribution represents a significant shift in data center design, but it also introduces safety considerations that need to be studied extensively," said Manish Kumar, EVP of Secure Power & Data Centres at Schneider Electric.

"Our work with some of the world's leading hyperscalers provides engineers and safety professionals with one of the first practical frameworks for evaluating arc flash risks. It offers a structured approach to understanding fault behavior, establishing safe work practices and designing effective protection schemes. Our goal is to help the industry move toward higher-voltage architectures with confidence and safety."

Design choices

The analysis argues that current standards remain useful but may produce conservative estimates that do not reflect how complex DC systems behave in practice. Software-based modelling can help engineers judge real risk by accounting for topology, converter response, switching logic and active protection measures.

That position was echoed by ETAP, whose software was used in the modelling work.

"Industry standards remain essential for arc flash and electrical safety, but traditional methods can be overly conservative because they do not fully reflect how complex DC systems operate," said Tanuj Khandelwal, CEO of ETAP.

"To understand real risk, engineers must evaluate system topology, fault behavior, protection coordination, converter response, switching logic and active protection schemes. ETAP enables teams to model and validate 800 V DC systems as they perform, helping move from conservative assumptions to more accurate, AI-augmented, physics-based safety and operational decisions."

Schneider Electric has also carried out testing on live-swap power arrangements in 800 VDC systems for maintenance work. The analysis is presented in a white paper titled 'DC Arc Flash Analysis: A Practical Study on 800 VDC in Data Centres'.