Relay Shield for Arduino Uno, 4 relays
The Relay Shield 4x(4 relay)- enables you to manage consumer devices connected to the network 220V, switching power equipment: motors, pumps. Total have 4 relays with switching characteristics: AC 250V-10A, DC 60V-10A.
Normaly relay is that it separates the control channels and traffic channels. That gives protection to your microcontroller. But there is no guarantee of protection from very high currents.
We have improved the shield for greater security:
1. We placed the relays and the terminals themselves outside the area of board Arduino,
2. We optocoupler (4-channel optocoupler TLP521-4) for isolation the relays from microcontroller, now the Arduino circuit and signal outputs are not switching relay itself.
3. The tracks connecting the relay board and terminals have an additional layer of solder to withstand high loads.
For flexibility in the use of I/O of the Arduino, relay control channels can be connected to any D0-D13 Arduino, with jumpers (Wire jumper). It means you are not tied to any I/O.
Each channel relays have LED indication.
For Relay Shield need external power supply 6-12V. For Relay Shield, use current about 400mA. With a jumper you can switch the power supply from an external to Vin board Arduino.
Shield have a small soldering area for install the components of your project. What adds more features and logic for relay control.