MELSEC-A Series PLC Programming Units Y2K Technical Bulletin

This technical bulletin addresses the Year 2000 (Y2K) problem for specific Mitsubishi MELSEC-A Series PLC programming units, detailing date rollover and leap year compensation behavior. It notes that A6GPP, A6PHP, and A6HGP models (running CP/M) require no action, while A7PHP and A7HGP models (running MS-DOS 3.21) may reset to 1980 after a power cycle in 2000, requiring a one-time DATE command reset.