For our project, we decided to control multiple devices:
- The lighting of LED’s through a photocell light sensor;
- Ignition of a heating resistor thanks’ to a temperature sensor;
- A pump that will be operated continuously;
- A ventilator which will also be also operated continuously.
For this, we bought a relay that allows separating the control part (Arduino) and the power unit. We chose 4 relay of the model “Songle: SRD-05VDC”. It has the following characteristic: 10A 250V / AC. It is important to know this information because it means that it is not possible to install equipment more than 2500 W because the relay doesn’t accept a current stronger than 10A for 250V voltage. The relay type corresponds to our project because it has male pins specially adapted for Arduino. In addition, it has a mounting hole in each corner that will fix on our plate behind the aquarium.
For the relay supply, it has two pins: a pin to 5V and the other to link to the mass. The control of the relay is connected against a single pin and can be performed during the change of the voltage. Indeed, the change occurs when voltage pass off 5V to 0V.
See you soon everyone!