Programmable load

A programmable load is a type of test equipment or instrument which emulates DC resistance loads normally required to perform functional tests of batteries, power supplies or solar cells. By virtue of being programmable, tests like load regulation, battery discharge curve measurement and transient tests can be fully automated and load changes for these tests can be made without introducing switching transient that might change the measurement or operation of the power source under test.

Implementation

A programmable load is simply a programmable power supply that applies a voltage but sinks current rather than sourcing it. By changing the current direction, the programmable load electrically "looks like" a programmable resistor rather than a programmable (Thévinen) voltage source.

Vendors

Most companies that make range of instrument power supplies will typically also sell programmable loads. A short (but certainly not complete) list of vendors include:

• Agilent Technologies
• NH Research
• ET Power Systems
• All Programmable Electronic Load Manufacturers