Electronic Loads

Electronic Loads

Electronic loads are active instruments that absorb and dissipate electrical power from a device under test (DUT), simulating real-world load conditions in a precisely controlled and repeatable manner. Unlike passive resistive loads, they allow instant software-controlled reconfiguration across four fundamental operating modes: constant current (CC), constant voltage (CV), constant resistance (CR), and constant power (CP). This flexibility makes them essential for characterizing DC power supplies, battery packs, DC-DC converters, fuel cells, and photovoltaic panels without requiring physical field loads or dedicated resistor banks that must be manually reconfigured.

Modern programmable electronic loads support dynamic load pulsing at frequencies up to several kHz for testing power supply transient response and output capacitor sizing. Automated sweep functions generate complete V-I and power curves in a single test sequence. Keithley 2380 series and AMETEK programmable loads cover DC requirements from watts to kilowatts, while the AMETEK California Instruments 3091LD extends capability to AC electronic load testing. Built-in voltage, current, and power measurement functions simplify integration into automated test systems via GPIB, USB, and LAN, eliminating the need for separate DMMs in many workflows.

Typical Applications

• DC power supply characterization: load regulation, line regulation, ripple and noise measurement
• Battery pack discharge testing, capacity verification, and internal resistance measurement
• DC-DC converter and voltage regulator efficiency mapping across load and input voltage sweep
• Solar panel and fuel cell I-V curve characterization for maximum power point determination
• Transient load testing for power supply stability analysis and holdup time validation
• Burn-in and production functional testing of power electronics assemblies on the manufacturing line

Popular Brands

Keithley (Tektronix) offers the widely used 2380 series programmable DC electronic loads for R&D and automated test. AMETEK Programmable Power supplies high-power AC and DC loads through its California Instruments and Sorensen divisions. Chroma ATE provides modular and standalone electronic loads targeting production ATE environments. Kikusui, ITECH, and BK Precision offer cost-effective options suited for general-purpose bench and educational applications.