Series 2280 Precision Measurement DC Power Supplies Reference Manual Section 2: General operation077085501 / February 2015 2-63Constant voltage (CV) and constant current (CC) modeThe Series 2280 power supplies feature a constant voltage/constant current automatic crossover.This feature permits continuous operation in the transition from constant-voltage mode toconstant-current mode as the load changes. The intersection of the constant-current andconstant-voltage modes is called the crossover point. For more information, refer to the followingfigure.Figure 57: CC and CV modeFor example, if the resistive load is such that the power supply is operating in constant voltage mode,the power supply provides a regulated output voltage. The output voltage remains constant as theload decreases until the preset current limit is reached. Then the crossover occurs. At that point, theoutput current becomes constant and the output voltage drops in proportion to further load decreases.Crossover is indicated by the front panel CC and CV messages. If the CV message appears, theinstrument is operating in constant-voltage mode. If the CC message appears, the instrument isoperating in constant-current mode.For this example, connect a 5 resistor to the bonding posts on the front panel, set the voltage to 5 Vand current limit to 2.5 A, and turn on the output. The power supply is operating in CV mode. Fordetails, refer to the following figure.
