First we will learn how to set up the power supply to produce a constant voltage signal.
Voltage is a relative quantity.
To supply a voltage you therefore need two connectors. The only absolute reference for voltage is 'ground' - the voltage of planet earth. The voltage difference between these terminals is the voltage supplied. The fixed port supplies a constant voltage of 5V. Ports A and B can supply any voltage between 0 and 20 volts. The output of any of these ports may be made relative to ground by connecting either the red or black terminal to the green ground terminal on the far left of the instrument.