Okay I will be quick. I am making a home automation project using hc-o5 module, arduino nano and 8-channel relay board.
this is how my relay looks like
now my connections are
in1 to d2 arduino
gnd to gnd arduino
vcc to vcc arduino
i dont use jumper neither the jumper side gnd
for bluetooth txd to rxd
rxd to txd
gnd to gnd
vcc to vcc
i used a breadboard side part, I think so it is called power bus to expand the gnd and vcc of arduino.
I am powering my arduino using a usb cablethrough computer
sometimes even from a 10000mah power bank which gives a max output of 5V
now the problem is after all the connections the relay light turns on. But the apliance connected never turns on.
This is how I have connected-