400 kVA Generators

Powerful, Dependable 400 kVA Power Generation

A 400 kVA generator sits firmly in the industrial power bracket, offering enough capacity to support large commercial premises, manufacturing facilities, and major construction projects. Whether you need continuous power for remote operations or dependable backup should the grid fail, a 400 kVA diesel generator provides the output and reliability that demanding applications require. Many customers refer to this size as a genset rather than a generator, and the two terms are used interchangeably throughout our range, from smaller standby diesel generator options right through to this larger 400 kVA genset.

Most of our customers in this bracket are running 3 phase electrical systems, and a 400 kVA 3 phase generator is built specifically to handle that kind of balanced, high-capacity load across commercial and industrial sites. For sites already wired for three-phase supply, a 400 kVA 3 phase diesel generator delivers smooth, stable power to motors, HVAC plant, and other heavy equipment that single phase supply simply can’t support. Some buyers know exactly what they’re after and search specifically for a 400 kVA 3 phase genset or a 400 kVA 3 phase diesel genset, and our range covers that requirement directly.

Silent Running for Noise-Sensitive Sites

Where noise matters, a 400 kVA silent generator makes a significant difference to how a site operates day to day. Every silent generator in our range is fully canopied, with an acoustic enclosure engineered to reduce operating noise substantially compared to an open-set equivalent. This makes a 400 kVA silent diesel generator particularly well suited to hospitals, city-centre developments, hotels, and residential-adjacent construction sites, where planning conditions or simple good neighbourliness demand a quieter solution. The sound attenuated canopy also protects the internal components from the weather, which is a genuine benefit for units installed outdoors on a permanent or semi-permanent basis.

Built for Industrial and Construction Applications

An industrial diesel generator at this output level is typically specified where standby power alone won’t cut it, and continuous or prime power output is genuinely needed. Depending on how the set is configured and loaded, it can serve as either a standby power source for critical infrastructure or a prime power rating unit running for extended periods on a construction site generator setup where no mains connection exists yet. This flexibility is one of the reasons 400 kVA units are so widely specified across UK and international projects, from data centres to large-scale builds.

Every generator in this range runs on diesel fuel and is built around a robust industrial diesel engine paired with a brushless alternator for stable, reliable output. A digital control panel gives operators clear, real-time monitoring of the set’s performance, and where required, an auto mains failure function allows the generator to start automatically and take over the load the moment mains power drops out. This is typically managed through an automatic transfer switch, which safely switches the site’s supply between mains and generator power without manual intervention. All models meet Stage V emissions standards, keeping them compliant with current environmental regulations for diesel generation equipment.

As standard, all our 3 phase generators in this range run at 415V three phase and operate at 50Hz frequency with an engine speed of 1500rpm, matching the standard requirements of the UK and the majority of our 50Hz export markets. If a 400 kVA unit doesn’t quite match your power requirements, our 300 kVA and 500 kVA generators offer a similar specification either side of this output.

As an authorised Cummins reseller, we’re able to offer the best pricing on Cummins generators from the UK, backed by a team with over 50 years of combined industry experience and a substantial physical stock holding that supports fast delivery across the UK and efficient global export.

Frequently Asked Questions

Reserve Your 400 kVA Generator

Ready to secure your 400 kVA generator? Get in touch with our expert team today by phone, WhatsApp, email, or our enquiry form to discuss your requirements, get a tailored quote, or reserve your generator from our current stock.