The module can be controlled directly from microcontroller pins (for example, Arduino).
Maximum load current 10A @ 250V, dimensions: 13.9sm x x 5.2sm 1.7sm
If you want the full optical isolation, connect the "Vcc" to the output of + 5V Arduino. Do not connect to Gnd. Set jumper Vcc to JD-Vcc. Power transistors and relay coils get by connecting "+ 5V" concluded "JD-Vcc".
If you have enough insulation relay, leave the jumper Vcc to JD-Vcc in place and simply Energize the module from the conclusions Arduino + 5V and Gnd and.
The relay is closed if the file to the control input logic low (LOW), then the LED lights. If you submit a logic one level (HIGH), will opening relay.