Electrical Power Supply

Voltage-regulated power supplies are necessary equipment in scientific and technical laboratories. They provide an adjustable, regulated source of electrical power to test circuits under development.

Laboratory power supplies usually feature two programmable modes, a constant-voltage output over a selected range of load current and a constant-current output over a wide range of voltage. The crossover point where the action switches from constant voltage to constant current action is selected by the user. As an example, it may be desirable to limit the current to a test circuit to avoid damage if a hidden circuit fault occurs. If the circuit demands less than a selected value of current, the regulating circuitry will hold the output voltage at the selected value. If, however, the circuit demands more than the selected maximum current, the regulator circuit will decrease the terminal voltage to whatever value will maintain the selected maximum current through the load. The powered circuit will never be allowed to carry more than the selected constant-current limit.