CIU means customer interface unit, it using together with prepaid meter, customer can inquiry electricity and recharge. The communcation between meter and CIU through PLC or MBUS.
FAQ
If customer need to change CIU, how to do?
First setp unpaired the meter, then use the new to paire the meter.
The PLC type CIU can communicaton with meter when power off?
Yes, it can communcation with meter when pwer off.