Hi community. I have a question on something i built and i would like to listen to your thoughts about it. I have made a very simple circuit that consists of a power unit connected directly to the input of a boost dc-dc voltage converter that has both CV and CC modes. The output voltage of the converter falls on a resistor that consists of a precision 20 kOhms ten turn potentiometer in series with a 330 Ohm resistor. The output voltage of the converter has been regulated to 59 Volts , while the output current of it has been limited down to 80 mA max through the CC mode. When i turn on the power unit , i see exactly what i expected to , a 80 mA current running through the resistance , in the case I have turned the pot down to 0 Ohms.
But , when i connect a DPDT switch to the output of the converter , while the rest of the circuit remains the same , things change and i cannot understand why. In specific , the CC mode of the converter seems not to work , as when i turn on the power unit and turn the pot down to zero , the current is almost equal to 59(V)/330(Ohms)=178mA , and not 80 mA as it would suppose to be , with my CC regulation. What changes with the DPDT?
But , when i connect a DPDT switch to the output of the converter , while the rest of the circuit remains the same , things change and i cannot understand why. In specific , the CC mode of the converter seems not to work , as when i turn on the power unit and turn the pot down to zero , the current is almost equal to 59(V)/330(Ohms)=178mA , and not 80 mA as it would suppose to be , with my CC regulation. What changes with the DPDT?