Electronic loads

Electronic loads are used for testing power sources, power convertors and specific components like (automatic)fuses. In the old days this was normally done by a resistive load connected to a source. This will give you a good idea of the static performance of the source. But of course often the load of the supply is not static. And it often is not a 100% resistive load either. This is where the electronic loads are getting interesting. There are DC electronic loads and AC+DC electronic loads.

Applications for DC electronic loads are for example testing of DC power supplies, DC/DC convertors, different types of batteries, Fuel cells and Solar Panels. Most DC electronic loads do have four operating modes:

- Constant Current 
Use when the power supply is constant voltage output; And the device that use the power supply will sink current disregard the output voltage level of the power supply.

- Constant Voltage 
Use when the power supply's output current will change according to the voltage that battery remained.

- Constant Resistance 
Use when the power supply is constant voltage output; And the device that use the power supply is a linear load ( e.g. Resistor or light bulb )

- Constant Power 
Use when the battery under charge, needs to be charged slower when voltage increase , like constant power curve.

Depending on the Device Under Test (DUT) and the application, you can test the source behaviour in the different modes with changing load conditions. To stress the DUT even more you can program a dynamic load. How well is the DUT performing when you quickly change the load? The more advanced electronic loads even have the possibility to program a timing diagram including slew rate of the different load conditions. With the Multichannel loads you can combine this dynamic testing on multiple inputs. This is for instance interesting when you test PC power supplies with multiple outputs.

At TTMS we do have multiple suppliers for electronic loads. To give you a good overview of what is available we did split the selection in different categories.

Applications for AC loads are for instance AC power supply testing (single phase and three phase systems), testing of power inverters for instance from green energy (windmills, solar panels, water power plants etc), uninterruptible power supplies and automatic fuses/switchers. With AC electronic loads you don't have a constant voltage mode. The voltage and frequency are based on the device under test. With the more advanced AC loads you can also test crest factors and power factor.

We recommend you to contact us for helping you to select the right electronic load for your application. Most often we can also provide a demonstration model for evaluation. If your application needs something special we encourage you to contact us as well.

We do have several suppliers that can provide the unexpected.

Related subjects:

Bipolar power supplies