Electric-control relay valve for trailer

The utility model provides an electric-control relay valve for a trailer. The electric-control relay valve for the trailer comprises a valve body, a valve deck and a piston rod, wherein a cavity is formed in the valve body, the valve deck is arranged on the valve body, the piston rod is arranged in the cavity of the valve body in a sealed mode through an end cap and a thrust connector with an air source inlet in the middle, a first gap and a second gap are formed between the piston rod and the inner wall of the cavity of the valve body, the valve body is provided with an air control connector, an air outlet connected with an ABS valve and an air storage cylinder connector, an electromagnetic part controls the air storage cylinder connector to be communicated with the air outlet through the first gap, the piston rod controls the air control connector to be communicated with the air outlet through the first gap, and thus double passageways are formed; meanwhile, air is supplied to the air outlet independently,