Basetech bt-153 issue
The ground terminal is almost certainly not connected to the power supply output terminals.  To measure the output voltage of the power supply, you must turn the current limit knob up somewhat, and measure the voltage between the black and red output jacks.

With the current control turned to minimum, the supply probably won't output any voltage, as the current is limited to zero.

To test the current limit, set your meter to a current scale, and connect to the red and black terminals (again, the yellow ground terminal is not connected to the power supply output - it is just there to give you convenient access to the AC power ground). Start with the current control fully counterclockwise (minimum), turn the voltage pots up somewhat, then slowly turn the current limit knob clockwise - you should see increasing current on your meter, which should match the current indication on the power supply.