Tools/Electronics/GPR-6030D
The GPR-6030D is a regulated DC power supply. Hacksburg's GPR-6030D is owned by a member but has no restrictions on use. The supply can provide up to 180 W of output power, and has built-in overload and reverse-polarity protection. Output can be set anywhere between 0-60 V and 0-3 A using the knobs for voltage and current on the front panel.
Theory of Operation
To operate this supply, you set --upper limits-- for both output voltage and output current. The supply then initially tries to keep its output at the voltage limit, by allowing current to vary. This is called "constant voltage" (CV) operation, and the C.V. LED is lit when operating in this mode. If the current needed to maintain this voltage exceeds the current limit, then the supply operates in "constant current" (CC) mode instead, and the C.C. LED is lit instead of C.V.. In CC mode, current is held constant by allowing voltage to vary. This supply can therefore be used as either a constant voltage source or a constant current source! To provide constant voltage, set the current limit higher than the current your load will draw at the intended voltage. To provide constant current, set the voltage limit higher than the voltage needed to drive that much current through the load.
Usage
To set the voltage limit, first make sure the current limit is set high enough that you're in CV mode (C.V. LED is lit), and then adjust the voltage knobs until the readout above them indicates the desired voltage. Even if nothing is connected to the supply, you'll still need to turn current knobs at least a hair above zero to put it CV mode.
To set the current limit, temporarily short the - and + terminals together with a piece of wire or (ideally) a banana plug patch cord. The supply should be in CC mode, with C.C. lit. Adjust the current knobs until the readout above them indicates the desired current. Make sure the conductor you use to short the terminals together is large enough to safely carry the current you're dialing in.