Abstract: The high accuracy and reliability of the T0 signals is one of the most important prerequisites for Chinese Spallation Neutron Source(CSNS) target station spectrometer. Based on the CPLD(Complex Programmable Logic Device) and PMC(Peripheral Mezzanine Card) mother-daughter structure, T0 signal fan-out instruments were designed with a distributed architecture, including a special trigger signal receiver for the neutron chopper with 24 V level trigger. Before the first 1.6 GeV proton beam hits the target, the delay of all T0 signals have been adjusted correctly. These T0 signal fan-out instruments have superior flexibility, maintainability, scalability, which have been working for more than three years, and the whole T0 timing system has run smoothly and achieved high reliability. It has accumulated valuable experience for the higher demand of T0 signal fan-out instruments at the second phase spectrometer in the future.