What it is and what it connects
The Siemens 6GT2791-6AH20 is a 2-meter coaxial antenna cable for the SIMATIC RTLS (Real-Time Locating System) product family. It connects an FME female antenna port to an R-SMA male gateway or transponder input — the two most common RF interfaces in industrial RTLS deployments. Rated at 50 Ω characteristic impedance, it is sized for the 2.4 GHz ISM band where typical insertion loss runs 0.053 dB/m. That works out to about 0.11 dB total for the 2 m assembly — negligible for a typical reader-to-antenna run, but worth knowing if you are chaining multiple jumpers.
Build and environment
The cable jacket is halogen-free and silicon-free (FRNC — flame-retardant, non-corrosive), with a braided shield of tin-plated copper wires. That matters for plenum or enclosed cabinet runs where corrosive off-gassing during a fire is a concern. The sheath color is RAL 6034 (pastel turquoise), which is the standard SIMATIC RTLS cable identifier. Operating temperature spans -40 to +80 °C, same as storage and transport. Installation temperature is slightly tighter at -25 to +80 °C — meaning you can pull it in a cold warehouse but should let it warm before bending tight. Minimum single-bend radius is 31.5 mm; multiple-bend radius is 44 mm. Flame resistance carries UL 1685 vertical tray and UL 1581 sec. 1090 (H) ratings, plus ECE-R 118 for vehicle use. The cable is UV-resistant and RoHS-conformant.
Lifecycle reality — NRND
This part carries a manufacturer lifecycle status of NRND (Not Recommended for New Designs). That means Siemens will continue to support existing installations and likely still manufacture it for spares, but they are steering new projects toward a replacement. If you are filling a BOM for a new line, verify the current recommended successor with your Siemens contact before locking the BOM. For existing RTLS deployments, this cable remains the correct service part.