What is a 8 channel relay board?
Description. 8 Channel Relay Board is a simple and convenient way to interface 8 relays for switching application in your project. Input voltage level support TTL as well as CMOS. Easy interface with Microcontrollers based projects and analog circuits.
Does a relay increase voltage?
Relays control one electrical circuit by opening and closing contacts in another circuit. Nonetheless, relays can “control” larger voltages and amperes by having an amplifying effect because a small voltage applied to a relays coil can result in a large voltage being switched by the contacts.
How does a 2 channel relay work?
The relay has two outputs-normally open and normally closed (NO and NC). Connecting a circuit or device between one of these two pins, the common pin on the relay output, and a power source will allow you to toggle power to a circuit or device.
How can I control 8 channels of relays?
In this project, I use a Wemos D1 Mini as the wifi enable the controller to interface with the relay module using the IO expansion shield. The magic of this setup is using the IO module and soldering it directly onto the relay board. This eliminates the narly mess you see you when would typically have 8 channels of relays.
How do you connect power to a relay?
On my relay the power and ground connection were marked DC+ and DC- (unlike most of the other relays which I think were marked JD-VCC and ground) which meant that the DC+ took the positive and the DC- took the ground. OK, so now you have a way of getting power in to the relay so now you need to connect something to receive that power.
Can a 5V relay draw power from a GPIO?
Most of the guides I read used a 5v relay which means that you can draw power from your RPi. If you have a 5v relay there are lots of guides on YouTube / tutorial sites which show which GPIO pins you need to connect to your relay. Some jumper cables.
What are the power and ground lines on a relay?
Typically the wire with the dashed line is the positive and the one without is the ground. On my relay the power and ground connection were marked DC+ and DC- (unlike most of the other relays which I think were marked JD-VCC and ground) which meant that the DC+ took the positive and the DC- took the ground.