Arduino Controlled Relay Module VMA406

Using Arduino Motors, Mechanics, Power and CNC
1

Hello,

Simple problem here. I am using an Arduino Mega output to control a relay module (link below)

When I test the Arduino output, I see that it is providing 5V. However, when I connect up this relay module, the output voltage is down to 2.5V. I assume this means that the output able to supply enough current and is being pulled down? It's very odd because this relay module is called "ARDUINO® COMPATIBLE 5 V RELAY MODULE" and seems to be very commonly used. It appears to have a resistor and is driving a transistor, which then drives the relay.

When I just use the 5V output from the Arduino itself as the control, the relay works fine. Not sure what is going on here. Any advice appreciated.

As for schematic, it is the same as seen here: How to Set Up a 5V Relay on the Arduino - Circuit Basics

Thanks

2

Post a well lit and focused picture of your setup.

3

No code...so I can't see if you have set pinMode() for whatever pin you're using to OUTPUT.

Steve

4

Thanks guys! Code is way too long to share, but I knew it was a simple thing I was forgetting, and it was the PinMode.

Much appreciated!