I am trying to connect my Raspberry Pi 3 to a relay and power a small pump with that.
The relay I use: 8-Relay. I can use the water pump with 3V to 12V and I want to connect a 5V external power supply to the relay.
I've connected the Raspberry Pi and the relay according to this tutorial (External Power Supply + to Relay JD-VCC / EPS - to Relay GND / Raspberry Pi 3,3V to Relay VCC / Connected one GPIO pin).
I can switch the relay on and off, so far so good. But when I connect the relay output to the water pump nothing happens. When I connect the water pump directly to the external power supply then the water pump is turned on (so no problem with the pump).
What am I doing wrong?