This Opto-isolated will protect microcontrollers and sensors from high voltages leaking through, As a result, you can safely control larger appliances without the worries of high voltage feedback. You can also choose your trigger level by simply changing a jumper. For triggering at 5V place the jumper in its place, for triggering on GND you can simply remove the jumper.

Opto-isolated 2 channel 5V Relay Module Specs:

• Operating Voltage: 5V
• Trigger Voltage: 2V - 5.5V
• Output Current: 10A 30VDC/10A 250VAC