What it is

High-speed regenerative electronic load for testing next-generation data center power supplies.

The EA-ELR 21000 Dynamic Test System is a modular, rack-level regenerative electronic load built to exercise the high-dynamic power shelves and rack power supplies used in emerging 800 V data center power architectures. It scales in 30 kW steps, returns absorbed energy to the grid at up to 95% efficiency instead of dissipating it as heat, and delivers current slew rates fast enough to reproduce real-world load transients. A single 42U rack holds up to eight 30 kW units for up to 240 kW, and multiple racks combine into systems up to 1920 kW and 5120 A.

• System DC power up to 1920 kW
• DC voltage range 0–1000 V
• DC current range up to 5120 A
• Modular and scalable in 30 kW steps (30 kW per 4U unit)
• Up to 240 kW per 42U rack in a 0.6 m² (6.5 sq ft) footprint
• Current slew rate up to 12 A/µs at 240 kW
• 125% short-term overpower (500 ms), optimized for 800 V systems
• Regenerative energy recovery to the grid, efficiency up to 95%
• Regulation modes CV, CC, CP, CR with fast crossover
• Arbitrary function generator for programmable load profiles
• Two-channel rack emergency stop; optional NS (anti-islanding) protection
• AC input 380–480 V ±10%, 3-phase, 45–65 Hz

What it is used for

The ELR 21000 Dynamic Test System is positioned for high-dynamic data center power testing:

• Data center power supply and power-shelf testing — reproducing real-world, high-dynamic DC load behavior for next-generation rack power supplies
• 800 V architecture validation — evaluating compliance with the requirements of emerging 800 V data center power architectures
• Peak-demand validation — using 125% short-term overload to validate sudden power demands from installed CPUs and GPUs without oversizing the test system
• Regenerative (energy-efficient) load testing — returning absorbed energy to the micro-grid at up to 95% efficiency rather than dissipating it as heat
• Programmable load profiling — driving voltage or current with the built-in arbitrary function generator using sine, triangle, rectangle, or trapezoid waveforms, with test sequences saved and reloaded for repeatable runs

High slew rate and dynamic response

Fast DC transients. The DC output is engineered for fast, high-dynamic current output, reaching current slew rates of up to 12 A/µs at 240 kW. Achievable slew rate scales with the number of 30 kW units connected in parallel within a rack.

Short-term overpower. Each unit provides 125% power for 500 ms within nominal voltage and current, optimized for 800 V systems, so peak power demands can be validated without moving to a larger test system.

Regenerative energy recovery

Energy back to the grid, not into heat. In discharge mode the system feeds absorbed energy back to the micro-grid with efficiencies of up to 95%. Because the design does not dissipate that energy as heat, it reduces energy consumption and operating cost and lowers the cooling and air-conditioning load compared with a conventional dissipative load.

Scalable, high-density rack power

30 kW steps to 1920 kW. The compact 30 kW, 4U unit is the building block. Up to eight units integrate into a single 42U rack, 600 mm wide and 1000 mm deep, for up to 240 kW in a footprint of just 0.6 m². Racks combine on the Master-Auxiliary bus and Share bus, where a multi-device system behaves as a single device with symmetrical load sharing, scaling to systems of up to 1920 kW and 5120 A.

Control, programming, and interfaces

16-bit digital regulation with an arbitrary function generator. Regulation runs at 16-bit resolution with CV, CC, CP, and CR modes, fast crossover, and a selectable voltage control speed. The built-in AFG applies sine, triangle, rectangle, or trapezoid waveforms to voltage or current, with freely programmable progressions and saved, reloadable test sequences.

Broad, isolated interface set. Each unit carries galvanically isolated USB, Ethernet (1 Gbit/s), EtherCAT with 1 ms communication speed, and CAN FD, plus a front USB host for data acquisition, and a Master-Auxiliary bus and Share bus for parallel operation. Digital I/O provides three configurable inputs, three relay contacts, and three temperature-sensor inputs. Command languages and drivers are SCPI, ModBus, LabVIEW, and IVI, with EA-Power Control software.

System safety and integration

Built as a system, not just paralleled devices. The rack uses a single AC input and a two-channel emergency stop for safe shutdown: the emergency stop button sits on the front door, and the rear door is secured with contact switches that trigger the emergency stop automatically if the door is opened during operation. The system can be equipped with Network and Supply (NS) protection to prevent islanding and with an isolation monitor.

Why engineers pick it

It reproduces real transients, not just steady-state load. A fast DC output reaches up to 12 A/µs at 240 kW, so the load can follow the dynamic current steps a data center power shelf actually sees rather than only a static draw.

It tests at full voltage without wasting the energy. Up to 95% of absorbed energy is returned to the grid instead of becoming heat, cutting energy cost and the cooling infrastructure a dissipative load of this power would demand.

One platform scales from bench-scale to megawatt. The same 30 kW unit grows in 30 kW steps to 240 kW per rack and up to 1920 kW / 5120 A across racks, so a program can start small and expand without changing control philosophy or drivers.

It validates peak demand without oversizing. 125% short-term overpower for 500 ms covers the sudden CPU and GPU-driven peaks a data center supply must survive, so the test system is sized to nominal rather than to peak.

High power in a small footprint. Up to 240 kW fits in a 42U rack occupying 0.6 m² of floor space, keeping a high-power test cell compact.

Models and configuring

The system is ordered by target current and power. Single-rack models EA-ELR 21000 DTS-01 through DTS-08 cover 30 kW / 80 A up to 240 kW / 640 A in one 42U rack of one to eight 30 kW units. Multi-rack models DTS-16 through DTS-64 extend the same architecture to 480 kW / 1280 A up to 1920 kW / 5120 A. All models share a 0–1000 V range and an 800 V target application voltage; each carries its own maximum slew rate and short-term overpower figure, listed in the specifications.

Options across the range are water cooling in stainless steel, NS (anti-islanding) protection, and an isolation monitor.

Select your model and configure the system on this page. For a multi-rack build, the water-cooling option, NS protection, or a turnkey installation, contact W5 Engineering and we will scope and quote the full system with you.