120 mm planetary, 25:1 — torque and backlash limits
The GBX1200250554F is a straight-tooth planetary gearbox, 120 mm outer diameter, with a 25:1 reduction ratio. Continuous output torque is 230 N.m at 100 rpm and 30 °C; maximum intermittent torque reaches 368 N.m under the same conditions — the margin between continuous and peak tells you this unit handles moderate overloads without immediate derating, provided the duty cycle stays short. Maximum torsional backlash is 12 arc.min — that is the angular play at the output shaft when the input is locked. For positioning axes that reverse direction, this backlash value sets the repeatability floor; if the application needs tighter than 12 arc.min, this gearbox introduces a dead band the controller must manage or compensate.
Load ratings and bearing life at 100 rpm
Rated service life is 30,000 hours at 100 rpm and 30 °C — that is about 3.4 years of continuous run time before bearing or gear wear reaches the end-of-life criterion. The gearbox is lubricated for life, so no oil changes are scheduled; the sealed IP54 shaft output keeps contaminants out of the bearing cavity as long as the shaft seal is intact. Maximum radial force Fr is 1500 N at 100 rpm for the 30,000-hour target, applied at mid-distance on the output shaft. Axial force Fa is 2100 N under the same duty. If the application needs 2800 N axial or 2000 N radial, the bearing life drops to 10,000 hours — plan the replacement interval accordingly. The C 45 shaft material is standard medium-carbon steel; it handles these loads without surface hardening provided the force application point stays within the shaft shoulder.
Obsolete — sourcing through independent channels
Schneider Electric lists the GBX1200250554F as obsolete. Available through independent surplus and new-old-stock channels. No pin-compatible or footprint-equivalent alternative is documented by Schneider, so a substitution requires checking the mounting flange, shaft diameter, and keyway dimensions against the existing installation.