What it is and what the key ratings mean
The QJ72LP25-25: It uses an optical duplex-loop connection with SI type 200/250 µm cable — at 25 Mbps the span is 200 m between stations; drop to 10 Mbps and you get 500 m. Total network distance can reach 30 km, supporting up to 65 stations per network with 239 networks total. Transient capacity of 1920 bytes per frame sets the update cycle data volume; for large I/O maps or recipe transfers you need to stay within that. Per-station link point budget is (LY+LB)/8 + 2 LW ≤ 1600 bytes — exceeding that means a second network module or a different protocol.