Hello,
I'm a Newbie to electrical engineering and I bought 2 DIY kits. One on Aliexpress which works without any problems and one from Ebay where I only get 33 mA current from the power supply. I can only drive a small LED with it, if I connect a small DC motor it immediately goes into the limit and the red LED lights up. With the other Board, the DC motor runs without problems and everything can be adjusted as desired.
I have already read a lot here and found the PDF file operation-and-maintenance.pdf with various measuring points. I have measured all the points given there and all values are correct. I have already exchanged the 3 OP Amps TL081 with MC34071 but the problem remains.
I use an external power supply AC 24V 3A for the input of the boards.
If I don't connect anything to the output, I can regulate the voltage quite normally, it also works with the connected LED and 2 connected resistors, I can regulate voltage and current, but current no more than 33 mA. The 33 mA i measured with my multimeter, which I connected to the output alone. I have checked various components, everything is soldered correctly as on the working board. I can't find anything wrong and I don't know where to look.
I still don't understand the circuit diagrams that I found on the net and here, so I have problems finding out the cause.
Do you have an idea which components I could check to solve the problem and make it work like the other one ?
Best Regards
Stefan
I'm a Newbie to electrical engineering and I bought 2 DIY kits. One on Aliexpress which works without any problems and one from Ebay where I only get 33 mA current from the power supply. I can only drive a small LED with it, if I connect a small DC motor it immediately goes into the limit and the red LED lights up. With the other Board, the DC motor runs without problems and everything can be adjusted as desired.
I have already read a lot here and found the PDF file operation-and-maintenance.pdf with various measuring points. I have measured all the points given there and all values are correct. I have already exchanged the 3 OP Amps TL081 with MC34071 but the problem remains.
I use an external power supply AC 24V 3A for the input of the boards.
If I don't connect anything to the output, I can regulate the voltage quite normally, it also works with the connected LED and 2 connected resistors, I can regulate voltage and current, but current no more than 33 mA. The 33 mA i measured with my multimeter, which I connected to the output alone. I have checked various components, everything is soldered correctly as on the working board. I can't find anything wrong and I don't know where to look.
I still don't understand the circuit diagrams that I found on the net and here, so I have problems finding out the cause.
Do you have an idea which components I could check to solve the problem and make it work like the other one ?
Best Regards
Stefan