If your application does not pull the signal low (but rather disconnects), you can safely add a 1K resistor between LVGND and the high voltage input on the left side of the board.

I/O is pulled HIGH when not actively pulled to GND.

A HIGH state on the input corresponds to a HIGH state on the output and vice versa.

LV signals only act as outputs from the board.

HV signals only act as an inputs to the board.

Opto-isolators prevent high voltages from affecting the system receiving the signal.

Connect any microcontroller input or LV input to pins 1 through 8 of the LV OUTPUT side An opto-isolator is an electronic component that transfers electrical signals between two isolated circuits by using light.Connect any HV output signals to pins 1 through 8 of the HV INPUT side.Attach your LV ground to the LVGND pin of the LV OUTPUT side.Attach your LV power source to the LVIN pin of LV OUTPUT side.Attach your HV ground to the HVGND pin of HV INPUT side.Attach your HV power source to the HVIN pin of HV INPUT side.Low Voltage (3.3-5VDC) outputs which will be referred to as 'LV'.High Voltage (5-24VDC) inputs which will be referred to as 'HV'.The HVIN pin is used to select the voltage of input signals, while the LVIN pin is used to select the voltage of the output signals. Note that this board is able to adapt to the specific voltage ranges required of your use case.

Rather than hacking together several smaller boards or modifying less than ideal existing solutions, we developed this robust and simple optoisolator board ourselves. While retrofitting/updating CNC machines in our shop with Arduinos and Raspberry Pis, we realized very few options existed for cleanly connecting 24V signals to our favorite low cost development boards. With large screw terminals, clearly visible LEDs indicating state, and optional 2.54mm headers, this board is a breeze to work with. rhydoLABZ INDIA Opto-isolator Breakout - Description: This is a board from SPARKFUN is designed for opto-isolation. The latest revision (1.1b, shown below) now has screw holes for easy mounting. Feeding an input a LOW/grounded state will produce a LOW/grounded state on the output and vice versa. This 8 channel input optoisolator board accepts nominal voltages of 5-24V (max of 40V) on the input side, while generating clean and regulated 3.3-5V signals on the output side. These electronic components are used in a wide variety of communications and monitoring systems that use electrical isolation to prevent high voltage emitters from. Looking to interface high voltage or noisy signals with a microcontroller, Raspberry Pi, or Arduino? Look no further! An optoisolator (also known as an optical coupler, photocoupler, optocoupler) is a semiconductor device that transfers an electrical signal between isolated circuits using light.

Opto isolator