• Y. Zhao, J. Cao
  IHEP Beijing, Beijing

A DC Current Transformer (DCCT) as a standard diagnostic system for beam current plays an important role in BEPCII, the upgrade project of the Beijing Electron Positron Collider. Two DCCTs are operated in the BEPCII storage ring now, separated in electron ring and positron ring, used to monitor the beam current, the beam injection rate and the beam loss rate, meanwhile to help to calculate the beam lifetime. In this paper, the mechanical structure design, readout system and data processing are presented. The progress of DCCTs on each step of BEPCII commissioning, such as improving the beam lifetime，and solution of background noise, are also included.