Electronic loads, such as the Sorensen SL Series of DC Electronic Loads, are instruments that you would use to provide a programmable load when testing voltage and current sources, including power supplies and batteries. Modern electronic loads are actually sophisticated electronic test instruments that can offer a number of different modes, including Constant Current (CC) mode, Constant Resistance (CR) mode, Constant Voltage (CV) mode, and Constant Power (CP) mode.

The Sorensen SG Series is one of the most popular high power programmable DC power supplies on the market. The SG Series is designed for exceptional load transient response and low noise output. With a full 15 kW available down to 20VDC output in a 3U package the SG Series leads the industry in power density. The power density is enhanced by a stylish front air intake allowing supplies to be stacked without clearance between units.

To ensure that automotive electronics can withstand the voltage transients induced on the power bus, companies use expensive arbitrary waveform generation and coupling networks during the design phase. For production test, however, a simpler and less expensive means for simulating bus voltage variations and transients is required. For many transient tests, all you need is a switching power supply and an electronic load.

Modern electronic loads, such as the AMREL SL Series, are versatile test instruments that should be part of every test engineer's toolbox. Here are some tips on how to use them properly.

In many applications, a DC power supply has to drive a load with a large ripple component. Examples of this type of load are DC-AC inverters, DC-DC converters, and DC motor loads. Linear supplies can normally handle this kind of load easily, but when you use a switching power supply, such as the Sorensen SG Series or Sorensen ASD Series, to drive this type of load, you may encounter some unexpected (and undesirable) problems.

The nature of the load that will be connected to the AC power source is very important in determining the correct type of supply. Generally loads can be classified as linear or non-linear. Linear loads consist exclusively of reactive, inductive or resistive components and can thus be modeled as an LCR network.