Electronic Loads – Made in Germany
For over 30 years Höcherl & Hackl has been developer and producer of electronic loads and testing devices for power supply, energy storage units and fuel cells.

DC LOADS
Our DC loads set the standard for precision, efficiency and versatility. With a power range from 150 to 28,800 W, they are the ideal choice for research, development and industrial applications. Whether air-cooled or regenerative, our units guarantee maximum reliability and optimum results.
With advanced technology and robust design, our DC loads enable you to efficiently test DC systems, reduce operating costs and increase productivity. They are flexible to use, space saving and designed to meet a wide range of test requirements.
TRL Series
Mobile Regenerative
- Input voltage up to 1,200 V
- Load current up to 60 A
- Power 1,000 W
- Energy recycling to local power grid
- Mobile mains connection via plug
PLA Series
Small
- Input voltage up to 800 V
- Load current up to 120 A
- Power from 200 W to 1,500 W
- Digital Master-Slave operation
- Load inputs at front and rear
- Lasteingänge auf der Front- und Rückseite
PLI Series
Powerful
- Input voltage up to 1,200 V
- Load current up to 2,700 A
- Power from 600 W to 28,800 W
- Large functional scope
- High dynamic
SCL Series
High Current
- Input voltage up to 12 V or up to 40 V
- Load current up to 1,200 A
- Power from 600 W to 1,800 W
- High current carrying capacity
- Modern touch operation

AC LOADS
Our AC loads are characterized by precision, flexibility and an impressive power range from 400 to 3 x 8,400 W. They are perfectly suited for tests in AC and DC operation and cover a wide range of applications with a frequency range of up to 1,000 Hz. Whether for research, development or quality control, H&H AC loads are optimized for every application.
The model range includes single and three phase loads for maximum versatility. A Robust construction and a wide range of features ensure high load capacity and reliable test results, even in demanding test environments.
ACL Series
1 or 3-Phase
- Voltage up to 3 x 500 V
- Load current up to 3 x 60 A
- Power from 3 x 1,400 W to 3 x 8,400 W
- Frequency range up to 1,000 Hz
- For three-phase applications

MULTICHANNEL LOADS
Our multi-channel loads are the perfect solution for testing multiple specimens simultaneously. They are particularly useful in the automotive industry for testing ECUs and other components. With up to 72 channels per system, they provide maximum efficiency, saving valuable time and money.
Each channel supports input voltages up to 240V and load currents up to 120A, enabling versatile and demanding tests. Modular and compact, they fit perfectly into 19″ racks and offer flexible application options.
PMLA Series
Multi-Channel
- Input voltage up to 240 V per channel
- Load current up to 120 A per channel
- Power up to 1,800 W per device
- Up to 12 channels in 19″, 2 U
- Modular conception

POWER DISTRIBUTION UNIT
Our power distributions are the ideal solution for centralized and reliable power in professional 19″ racks. They integrate seamlessly into complex test environments, providing maximum security and flexibility.
With voltages up to 3 x 400 V and currents up to 32 A, they provide reliable performance in demanding applications. Features such as a central emergency stop switch and versatile power supply combinations ensure safety and adaptability.
SE Series
Central Mains Supply
- Voltage up to 3 x 400 V
- Current up to 32 A
- Various mains configurations
- Emergency stop function

DC POWER SUPPLIES
Our bi-directional DC power supplies combine source and load functions in a single unit, making them the ideal solution for today’s e-mobility and energy storage test requirements.
With 2 or 4-quadrant devices, the voltage ranges up to 100 V, the load current up to 320 A and the power up to 3,600 W. Testing PV inverters, energy management systems or electric vehicles are classic applications for our source sinks.
QL Series
Source-Sink
- Voltage up to 100 V
- Current up to 220 A
- Power up to 3,600 W
- 2- or 4-quadrant version
PRD Series
Network Simulator
- Bidirectional DC power supply
- Regenerative in load operation
- 30 kW in 3 U

AC POWER SUPPLIES
Our AC power supplies are ideal for testing PV inverters, energy storage systems, UPS and other applications. With state-of-the-art technology and flexible application options, they set the standard for precision and efficiency.
The units provide outputs from 6 to 22 kVA with output voltages up to 450 V. The PRE series can also be used as a mains simulator. The compact design allows them to be accommodated in little as 3U.
QL Series
Source-Sink
- Voltage up to 100 V
- Current up to 220 A
- Power up to 3,600 W
- 4-quadrant version
PRE Series
Network Simulator
- Regenerative 4-quadrant AC source
- 6 … 22 kVA in 3 U
- Output voltage max. 450
What are electronic loads?
In contrast to a power source, electronic loads are a current sink. It is an intelligent device that is used to replace a conventional (ohmic) load resistor.
While when loading a voltage source with a fixed resistor, only a certain load current can be set by a certain resistance value, the special feature of the electronic load is that the load current can be set within a defined range. It is controlled electronically.
Electronic loads find use in a wide range of applications, especially for testing power supply and control units, batteries, fuel and solar cells, generators, transformers, uninterruptible power supplies (UPS), on-board power systems and many more.
Furthermore, electronic H&H loads have a versatile range of functions, which promises a comfortable use with a high automation potential. With functions such as MPP-Tracking, Discharge function, Internal resistance measurement, etc. complex measuring and data acquisition processes are automatically carried out by H&H loads, thus increasing their range of applications.
Also essential for automated test stands are analog and digital interfaces, which H&H loads usually have in standard design.
What are electronic loads used for?
Depending on their type and range of functions, electronic loads are suitable for a wide variety of applications. Mostly they are used for testing different electronic components, but they are also used as flexible adjustable controllers of different manipulated variables (current, voltage, power, resistance).
DC-Loads
DC loads are used for testing the following components:
- Power supplies, bench power supplies
Static or dynamic load in different operating modes, burn-in test. To determine the V/I characteristics of power supplies from open circuit voltage to short circuit, electronic loads are also needed that can regulate high load currents at input voltages close to 0 V. For this purpose there are special models of DC loads: PLI ZV series. - Control units
When testing control units, simultaneous loading of several different units is often required by simulating different consumers, e.g. in a vehicle. We serve such applications with our modular multi-channel load series PMLA. - Power distribution, wiring harnesses, fuse boxes
Here, too, many different consumers are simulated by several channels of a PMLA multi-channel load. - Batteries and accumulators
Energy storage devices are discharged continuously or with defined load profiles to evaluate their quality. With the discharge function this is done professionally including protection functions and individual switch-off criteria. To cycle accumulators, devices for charging and discharging are necessary. For this purpose, either a power supply can be added to the system in addition to the electronic load, or a source-sink from H&H, which switches seamlessly between charging and discharging mode. It is available as a 2- or 4-quadrant power supply. - Fuel cells
The PLI ZV zero-volt models are also used for testing fuel cells, since they deal with voltages far below 1 V at high currents. Impedance spectroscopy is used to analyze fuel cells, e.g. to determine the series resistance or the end of life (EOL). - Photovoltaic panels
For PV panels, the maximum power point (MPP) plays a central role. Our DC loads offer the MPP tracking function either standard or optional, depending on the series. For applications with high demands on the accuracy of current control over wide ranges, we have models with several selectable current setting ranges in our portfolio: PLI MR series. - Testing and simulation of electronic components
such as diodes, rectifiers, fuses …
Testing of the continuous, short-time or pulsed current capability of active and passive components. With the V/I-characteristic function of the PLA series, the characteristic curve of a component is mapped in the electronic load. Depending on the applied input voltage, the load sets the corresponding load current.
AC Loads
AC loads are used in these areas:
- AC power supplies testing
- Transformer testing
- Inverter testing
- Testing uninterruptible power supplies (UPS)
- Aircraft electrical systems testing
- Testing generators
- Burn-in test
- Smart grids, micro grids testing
- Testing chargers, charging columns, wallboxes
- Testing energy meters
- Testing according to standards, safety tests