Electronic Loads - Versatile Test Solutions for Industry

Electronic Loads in Research, Development and Testing

Electronic AC and DC loads form the basis for precise performance and reliability tests in the field of power supply as well as with other electrical sources and loads. Developers, test engineers and specialist users use them to simulate real load situations, verify standard requirements and measurably ensure product quality. With integrated software functions such as profile editor, sequencer and logging, test teams plan, control and document test sequences efficiently and reproducibly.

Performing DC Tests with Electronic DC Loads

Test engineers and developers use electronic DC loads to examine the behavior of DC sources and energy storage systems under defined, realistic load conditions. As programmable DC sinks, they specifically simulate electrical load conditions and enable precise analysis of performance, stability and control behavior.

Typical applications in the DC field include tests on batteries, fuel cells, DC power supplies, DC/DC converters or photovoltaic components. Specialist users examine discharge curves, internal resistance, load steps and dynamic responses. The measurement results are reproducible and comparable.

Electronic DC loads operate in various control modes, such as CC (Constant Current), CV (Constant Voltage), CR (Constant Resistance) or CP (Constant Power). In CV mode, the load regulates the current so that a specified voltage is maintained at the input. These modes simulate defined operating conditions and help technicians test and compare components under controlled conditions.

Using programmable functions such as sequences, list mode and trigger I/O, test teams create dynamic load profiles and perform targeted load tests.

Many electronic loads also offer remote sense for more accurate voltage sensing directly at the device under test, integrated protection functions such as OVP, OCP and OPP as well as interfaces for SCPI, API, LAN or USB control. This allows test engineers to integrate the instruments efficiently into automated test systems (ATE).

Application Areas of Electronic DC Loads

Specialists in test engineering use electronic DC loads to apply targeted loads to DC sources and DC outputs. Typical devices under test include:

• DC power supplies, programmable DC sources and other DC supplies
• DC/DC converters
• Batteries and battery modules for discharge, capacity and internal resistance tests
• Fuel cells
• PV modules, PV strings and PV simulators
• LED drivers and LED current sources
• DC generators or rectified generator outputs
• digital outputs, control units and electronic assemblies with DC supply

Electronic AC Loads for Practical AC Testing

An electronic AC load can simulate an ohmic resistor as a pure active resistance. Depending on the device, it can additionally simulate inductive or capacitive load components. This makes it possible to test how an AC system responds to reactive power, phase shift and changing power factors.

Electronic AC loads simulate different load profiles. Adjustable parameters include, for example, constant current, constant power, power factor and phase angle.
Depending on the device, non-linear loads with harmonic components can also be simulated. This makes it possible to test how stable a device under test operates under changing AC load conditions. At the same time, it shows whether control, efficiency and protection functions respond reliably.

Multi-phase AC loads with synchronization support specialist users in the practical testing of single- to three-phase systems. By analyzing the alternating current, they evaluate efficiency, grid effects and safety behavior with high accuracy.

Application Areas of Electronic AC Loads

Technicians and test engineers use AC sinks for tests on:

• Transformers
• On-board networks (12 V, 24 V, 48 V, automotive)
• UPS systems (uninterruptible power supplies)
• Frequency converters and inverters
• Power filters and PFC stages
• Motors via converters
• Generators

FAQ – Frequently Asked Questions About Electronic Loads

What is an electronic load and how does it work?

An electronic load simulates electrical loads by absorbing energy from an electrical source. Conventional electronic loads convert this energy mainly into heat. Regenerative loads can return part of the absorbed energy, for example to the supply grid or to a suitable DC link. This allows different load conditions to be set reproducibly and the behavior of power supplies, energy storage systems or other electrical sources to be analyzed.

What do the operating modes CC, CV, CR and CP mean?

These operating modes define which electrical quantity remains constant:

• CC (Constant Current): The load keeps the current constant.
• CV (Constant Voltage): The load regulates the current so that a specified voltage is maintained at the input.
• CR (Constant Resistance): The load simulates a constant resistance.
• CP (Constant Power): The load absorbs a defined power.

These modes allow developers to precisely simulate real operating conditions.

How do specialist users apply dynamic load profiles?

With dynamic load profiles, specialist users program changing load conditions, such as load steps, startup processes or defined load cycles. Sequences and trigger functions create reproducible test procedures for functional, lifetime or stress tests.

Which protection functions ensure safety during tests?

Modern electronic loads protect the device under test and the instrument by detecting overvoltage, overcurrent, overload and overtemperature and triggering suitable protective measures. Depending on the device, these may include shutdown, current limiting or an error message to the test system.

Why is remote sense important for the electronic load?

Remote sense measures the voltage directly at the device under test instead of only at the instrument terminals. This allows voltage drops in the connecting leads to be captured more accurately. It improves measurement and control accuracy, especially at high currents or with longer cables.

How do test engineers integrate an electronic load into test systems?

Electronic loads can be integrated into automated test systems via interfaces such as LAN, USB or GPIB, as well as via command sets and programming interfaces such as SCPI or APIs. This allows test teams to control test sequences, log measurement values and evaluate results reproducibly.

What do specialists consider when selecting an electronic AC/DC load?

Important selection criteria include voltage range, current range, power, control dynamics, measurement accuracy, operating modes and communication interfaces. Depending on the application, cooling, noise level, form factor, protection functions, modularity and regenerative capability also play a role.

How does master/slave operation work?

In master/slave mode, specialist users connect several load modules to form a larger load system. The master unit controls the slaves synchronously and distributes the currents evenly. This allows test engineers to achieve higher total power levels and test systems up to the range of several hundred kilowatts.

What distinguishes electronic loads from LXinstruments?

LXinstruments distributes and develops electronic loads with high measurement resolution, fast control, versatile interfaces and comprehensive software. The modular concept enables flexible system solutions for laboratories, development and automated test environments.

Electronic Loads from LXinstruments

Electronic loads from LXinstruments combine technical precision with practical functionality. The portfolio includes DC and AC loads in various power classes that stand out through high dynamics, modular expandability and flexible control. The instruments support development departments, test laboratories and production areas in demanding measurement and validation tasks.

Product Portfolio and Benefits at a Glance

• Voltage ranges up to 2.25 kV and currents up to 20 kA
• Extended operating modes: power, resistance and shunt regulation
• Modular current sinks for mainframes with up to 40 individual modules
• Master/slave operation for power levels up to the range of several hundred kilowatts
• Extensive communication interfaces (SCPI, API, LAN, USB)

Contact and Consultation

The LXinstruments expert team advises companies, universities, research institutes and other technical organizations on the selection of suitable models, interfaces, integration options and test solutions – tailored to the respective test requirements and system environments. This ensures that you buy the right product with the required accessories.

Contact:
+49 (0)7032 89592-3

Together we will find the solution that fits your requirements.