Hitachi Seiki HG400 (1993)

SN HG40018 (has newer Mori Hitech Label on front)

Fanuc 15M/A control with Micon 16 III PLC controller

Problem:
When machine boots up the Micon 16III unit displays:
1120 PC Ladder Sum Check Error
I think all we need is the procedure to clear this alarm. It appears to be a matter of “flushing” some PLC memory buffer.

Anyone out there have any suggestions?