The Siemens 6ES7923-5BF00-0CB0 is a pre-assembled round cable purpose-built for the SIMATIC S7-1500 system, connecting the front connector module to the connection module on digital I/O modules. It carries 50 conductors at 0.14 mm² each, terminated with IDC connectors at both ends, and runs 5 m between interfaces.
Rating and fit for the S7-1500 backplane
Rated at 24 V with a maximum of 60 V, this cable is sized for the signal levels on S7-1500 digital I/O modules — 24 VDC is the standard field-side supply, and the 60 V ceiling covers any transient or auxiliary voltage the module might see on the channel bus. The 50-pole IDC interface mates directly with the 50-pin front connector module (first interface) and the 50-pin connection module (second interface), so it drops into the standard S7-1500 wiring scheme without adapters.
Deployment context
This is a panel-internal cable — unshielded, PVC-sheathed, round profile at 10.3 mm outer diameter. It runs between the front connector on the I/O module and the remote connection module, which is typically DIN-rail mounted in the same enclosure. The 5 m length gives enough reach to route through cable ducts or along the backplane without tension.
Listed as active in the Siemens lifecycle system, the 6ES7923-5BF00-0CB0 remains a standard catalog item for S7-1500 installations. It is not a phase-out or last-time-buy line.