Abstract: Aiming at the abnormal metering error of gateway metering system, the reasons caused the abnormal error were analyzed in depth, and the potential problems were investigated from different respects. Some improvement measures were adopted, which include adding a set of special current transformers (CT), testing the comprehensive error of the voltage transformers (PT), installing the gateway metering box near with the voltage transformers to reduce the secondary voltage drop of PT and others. Then the abnormal metering error, which existed in long term, had been eliminated, and large amount of economical losses was retrieved. 

Key words: metering error, problems investigation, reason analysis, improvement measures