| Series | Positioning | Example |
| MELSEC iQ-R | Medium–large systems | High-performance PLC/PAC, advanced manufacturing |
| MELSEC iQ-F | Small–medium / compact | FX5S, FX5UJ, FX5U, FX5UC |
| MELSEC-Q | Medium–large | High-speed, high-accuracy, scalable control |
| MELSEC-L | Compact modular | Space-constrained systems |
| MELSEC-F | Small / standalone | Compact PLC |
| MELSEC-QS/WS | Safety | Safety control applications |
| MELSEC-A | Legacy | Older/out-of-production family |