Connect the GND of the battery to the GND of arduino – common GND. If you are using a 5V relay instead of 12V relay, you only have to connect the arduino GND. I am using a 12V relay. So the coil ...

Need a powerful electric motor on the cheap? [Daniel Simu] and his friend [Werner] show us the ins and outs of using windshield wiper motors. Through many examples and disassembled components, the … ...

Driving a brushless DC (gimbal) motor can be a pain in the transistors. [Ignas] has written up a nice article not only explaining how to do just this with an Arduino, but also explaining a little ...

Omron has launched a PCB power relay that provides bi-directional high power DC switching for home renewable energy storage batteries and electric vehicles wall boxes – for example, in vehicle-to-home ...

So long as the 0V rail is connected to the Arduino 0V rail, the positive rail can be any dc voltage – more or less that the Arduino, so great for 12V motors. And it is compatible with both 5V and 3V ...