Instruction manual
19 
When the resistor’s value decreases so the output current value becomes equal 
to the current limit value,  power supply will go to constant current operation 
(see third row of the table). 
If the resistor value is  R =  1  Ù,  for  U
out
 = 5V, using Ohm’s law the output 
current is 5A. But this value is greater than current limit value, so the power 
supply limits the output current to the limit programmed value. That is why in 
the third row of the table  I
out
  = 2 A. In this case,  U
out
   is changed, too. Using 
Ohm’s law again, the output voltage is calculated using output current value 
and the resistor value, so it is 2 V. 
So the power supply will go to constant current operation when the output 
current value becomes equal or greater than the limit value. 
When the output current value becomes smaller than the limit value (by 
changing resistor’s value), the power supply will go back to constant voltage 
operation. 
In conclusion: 
CV:  U
out 
= U
lim 
and   I
out 
< I
lim 
CC:  U
out 
< U
lim 
and   I
out 
= I
lim
The following section will explain how to get the power supply in constant 
current operation mode and in constant voltage operation mode. 










