What it is

The EA-BT 20000 single-channel series is a two-quadrant battery tester with regenerative energy recovery: one 30 kW unit both charges and discharges a battery, feeding discharge energy back to the grid at up to over 96% efficiency. Autoranging output stages cover 0–10 V to 0–2000 V and ±40 A to ±1000 A, with integrated battery-test modes, CC-CV discharge characteristics, and an amp-hour counter. A separate three-channel version, the EA-BT 20000 triple-channel series, is available for testing three batteries independently from one device.

• Two-quadrant battery tester — charges and discharges from a single unit (positive and negative current)
• Regenerative discharge — recovers energy to the grid at up to over 96% efficiency
• Power: up to 30 kW per unit
• Output classes: 0–10 V to 0–2000 V; ±40 A to ±1000 A, model-dependent
• Integrated battery-test functionality — battery test mode, battery simulation, CC-CV discharge characteristics, amp-hour counter
• Autoranging constant-power output — full rated power across a wide voltage and current envelope
• Precise digital control — CV, CC, CP, CR with fast crossover; 16-bit ADCs and DACs; ≤1 ms communication via EtherCAT
• Built-in interfaces — USB, Ethernet 1 Gbit/s, EtherCAT, CAN FD, plus a 16-pole Digital In/Out; SCPI and ModBus with LabVIEW and IVI drivers
• Wide dual-range 3-phase input — 208 V or 380–480 V, auto-adjusting (30 kW models derate on a 208 V grid)
• Parallel operation to 64 units via Master-Auxiliary bus and Share-Bus — systems to 1920 kW and 64000 A

Two-quadrant operation with energy recovery

The BT 20000 is a two-quadrant device: it acts as a charger (source) and as an electronic load (discharge) from the same terminals, driving positive and negative current so a single unit runs a complete charge/discharge cycle without a separate supply and load.

In discharge mode it is regenerative: the energy drawn from the battery is converted back to AC and fed into the local grid at up to over 96% efficiency, rather than dissipated as heat. Two costs fall as a result — energy cost, because the discharge energy is recovered rather than wasted, and cooling cost, because the unit generates far less heat and needs less air conditioning. In many applications a single device is sufficient, reducing investment and installation cost.

The principle of autoranging

A conventional tester reaches full power at only one voltage-current point. The BT 20000 uses a flexible, power-regulated output stage (autoranging) that maintains full rated power across a wide range of voltage and current combinations, in both charge and discharge directions. One unit covers a working area that would otherwise require several fixed-rating instruments.

The result is a symmetric constant-power characteristic: as terminal voltage falls, the available current rises to hold the same wattage, on both the charge and discharge sides of the curve. For deep-discharge work this reaches down to very low voltages, with the high load current allowing maximum total discharge even below 2 V.

What it tests and simulates

Battery test for electro mobility. Tests the electrical characteristics of batteries across cell, module, and pack level, including State-of-Health (SOH) determination for second-life classification and end-of-line (EOL) test. Suits both standalone automatic test systems and integrated battery test, with the measurement accuracy, reproducibility, and reliability the application demands.

Battery simulation. Simulates batteries as single cells, modules, or packs to support the development of energy storage and the components powered by it. Used as a simulator, the tester also protects the connected component: overcurrent protection acts like a safety fuse, switching off and raising an alarm, while voltage monitoring can trigger functions and warnings when limits are crossed.

Battery recycling. Assesses retired EV batteries for second-life use, starting from an amp-hour-based State-of-Health check. Where too little capacity remains, autoranging allows full discharge before recycling, down to voltages under 2 V via the high load current, while regeneration to the grid at up to over 96% efficiency keeps the process cost-effective.

Why engineers pick it

One unit charges and discharges. Two-quadrant operation drives positive and negative current up to ±1000 A, so a single tester runs the full cycle instead of a separate source and load.

Recovers discharge energy instead of wasting it. Regeneration returns energy to the grid at up to over 96% efficiency, cutting both energy cost and the heat load that would otherwise drive air-conditioning cost.

Battery-test intelligence built in. Integrated battery test mode, battery simulation, CC-CV discharge characteristics, and an amp-hour counter, with 16-bit ADCs and DACs and ≤1 ms EtherCAT communication for fast, reproducible sequencing.

Precise, wide-range measurement. Voltage measurement accuracy to ≤0.05% FS and current to ≤0.1% FS across output classes from 0–10 V to 0–2000 V, reaching below 2 V for deep-discharge work.

Built-in test and control

Beyond source and sink, the BT 20000 integrates typical battery-tester functionality so that much of a test system lives in the device itself: battery test mode and battery simulation, CC-CV discharge characteristics, and an amp-hour counter. The unit is operated from a TFT control interface with rotary knobs, and the front-panel USB host logs data and runs sequences directly from a USB stick.

Control and monitoring extend through a 16-pole Digital In/Out block with three independent, user-configurable inputs, three independent dry-contact outputs, and three independent temperature-sensor inputs, so cell and pack temperatures feed the test alongside voltage and current. All communication interfaces (USB, Ethernet 1 Gbit/s, EtherCAT, CAN FD) are galvanically isolated from the DC side, with command support for SCPI and ModBus and LabVIEW and IVI drivers.

Scaling to high-power battery test systems

For higher power and current, units connect in parallel through the rear copper rails; a contact-protection cover is provided. The Master-Auxiliary bus lets the combined system behave as one device, with total power and total current reported on the master and slave-unit warnings and alarms appearing in its display, while the Share-Bus distributes load symmetrically across the connected units.

A 19 in cabinet with 42U provides a 240 kW system in roughly 0.6 m² (6.5 sq ft) of floor space. The Master-Auxiliary bus supports up to 8 cabinets and a maximum of 64 units. A 150 kW battery pack tester, for example, can be built from five 30 kW 4U units.

Choosing your configuration

This page covers the single-channel BT 20000, one 30 kW test channel per unit. If you need three independent channels in one device, see the separate EA-BT 20000 triple-channel series.

Select the output class by voltage and current:

• Ten output classes. 0–10 V / ±1000 A (10 kW) and 0–60 V / ±1000 A up to 0–2000 V / ±40 A (30 kW). Enclosure 483 mm (19 in) × 177 mm (4U) × 668 mm (26.3 in); overall depth from 802 mm (31.6 in). 50 kg (110 lb).

Then choose options:

• Water cooling in stainless steel — 56 kg (126 lb).

The dual-range input accepts 208 V or 380–480 V and adjusts automatically without configuration; on a 208 V grid the 30 kW models set a DC-power derating.

Configure your single-channel BT 20000 on this page — output class and cooling — then add to cart or request a quote. For the triple-channel series, multi-unit parallel systems, and cabinet integration, contact W5 Engineering.

Buy the EA-BT 20000 through W5 Engineering

W5 Engineering is your authorized North American distributor for EA Elektro-Automatik. Configure and order the BT 20000 directly on this page, with W5 support for output-class selection, channel configuration, parallel-system design, cooling options, integration, and availability.