The converter valve control and monitoring functions based on SIEMENS technology were analyzed for Jinsu （from Jinping to Suzhou） 800 kV UHVDC power transmission project. The signals between Valve Base Electronics （VBE） and Converter Control and Protection （CCP） were analyzed too. The reasons of VBE READY （VBE-RDY） null value and making VBE out of operation were researched while DC bus differential protection tripping of Jinping converter station simulated pole 2 high voltage converter during Jinsu 800 kV UHVDC system commissioning tests. Moreover， the principle of converter valve bypass and VBE-RDY null value were analyzed in detail. The VBE trip and converter block fault caused by VBE cabinet 110 V DC power loss test was analyzed and researched in pole 1 low voltage converter system commissioning tests. The solutions to solve above problems were proposed and will be put into practice in the following 800 kV UHVDC transmission project.