ITEM NAME:8 Way Solid State Relay Module Board Low Level Trigger 5V DC Output w/Fuse #JT1 Product Description Description: HY-M281 8 Way Channel Solid State Relay Module Board Low Level Trigger 5V DC Output DC Control AC with Fuse Feature: 1. DC + and DC - are used to connect the power supply of the module. The voltage is 5V. 2. The CH terminal is the trigger terminal of the module. When there is a trigger signal, the output switches (A, B) of the solid state relay will be closed and the load will be conductive. 3. Low-level trigger: In industrial control, called PNP trigger, negative trigger, that is, when the voltage is 0 V or close to 0 V before the trigger end and the negative pole of the power supply, the relay closes. 4. When the CH terminal has 0-2.5V, the solid state relay can be triggered to turn on. 5. When the CH terminal has 2.5-5V, the solid state relay is disconnected. Specification: Size: 100*48*21mm/3.93*1.88*0.82'' Note: Please allow 1-3mm differs due to manual measurement. Due to the different display and different light, the picture may not show the actual color of the item. Thanks for your understanding. Included: 1 x 8 Channel Solid State Relay Module.When there is a trigger signal, the output switches (A, B) of the solid state relay will be closed and the load will be conductive. Included: 1 x 8 Channel Solid State Relay Module. Due to the different display and different light, the picture may not show the actual color of the item.