This module is used when the actual operation requires isolation control and voltage conversion.It can realize 3.3V or 5V to control the interface of 3.6--24V voltage level. After the control terminal is turned on, the controlled terminal will also be turned on.Photoelectric isolation has strong anti-interference ability. Can drive big behindPower triodes, MOS tubes, etc., where high voltage driving is required, can also directly drive low power 24V relays.If it is a pulse signal, please note that the limit of 817 is 4KHZ. If the control signal is 4KHZ, please do not use this module, it will not work properly.Colour:GreenMaterial:PCBSize:48x42x38mmPackage Contents:1 x 817 Optocoupler 4 Channel Voltage Isolation BoardOnly the above package content, other products are not included.Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.