USB - RLY08 is a 8 relays driver circuit that connects via USB bus and can be controlled from any application that sends data over a serial port. With this circuit you can control up to 8 relays independently from any PC. The circuit has 8 relays of 1 circuit and two positions that can be controlled by commands sent from the PC. The circuit includes a converter USB to serial chip, so from the point of view of programming , all you have to do is send the desired control data to a serial port . This means that any program that sends data over a serial port can control the drive circuit and the relays as desired . The circuit is powered directly from the USB bus and also has a LED on each relay shows the current status of each channel .
If the voltage and current of the load connected to the relay are within the region bounded by the line point shown in the figure below , the relay can perform stable switching operation without problems for a long time. If the relay is used with a voltage or current higher than indicated , the contacts are spoiled much sooner shortened his life considerably or even destroying them. If you need to control larger loads , you should use greater capacity relays or contactors controller by these relays .