I am trying to control a relay from an Arduino compatible board. When I try to activate the relay from the Arduino it takes at least a second to switch closed and sometimes does not switch closed at all.
I am using this relay board. Here is the circuit diagram:
Digital pin 2 of the Arduino is connected to IN0 of this circuit (bottom left). I set it low to switch on the relay. VCC and ground on the low-voltage side are connected to ground and 5V pins of the Arduino. The high-voltage side (JD-VCC) is connected to a 5V 1A power adapter which also powers the Arduino. The jumper on the top left of the circuit connecting the high-voltage and low-voltage sides has been removed.
A photo of the assembled circuit is here.
Could someone please help me with the possible reasons why the relay switches with a delay?
One reason I suspected is that I have connected the power supply to the relay coils by thin jumper wires. But the specification says that the relay draws a current of 80 mA. So I was hoping that the wires would be good enough.