Planetary gearbox, 120 mm frame, 12:1 reduction
The GBX1200120701F: This is a Schneider Electric GBX-series planetary gearbox with a 120 mm housing diameter and a 12:1 reduction ratio. The straight-tooth design delivers 260 N.m continuous output torque at 100 rpm and 30 °C ambient, with a maximum intermittent torque of 416 N.m under the same conditions. Efficiency is listed at 94 %, which is typical for a single-stage planetary set at this ratio. The torsional backlash is 12 arc.min maximum — standard precision for a general-purpose positioning gearbox, not a zero-backlash servo unit. Service life is rated at 30,000 hours at 100 rpm and 30 °C, with the gearbox lubricated for life — no oil changes or regreasing intervals in the field. The shaft output seal carries an IP54 rating, meaning it sheds dust and splashing water but is not submersible.
Obsolete — sourcing through independent channels
Schneider Electric lists the GBX1200120701F as obsolete. This gearbox is sourced through independent surplus and new-old-stock channels. For a replacement, the closest functional match would be a current-production planetary gearbox in the same 120 mm frame size and 12:1 ratio from Schneider's BCH or Lexium series, but the mounting interface and shaft dimensions must be verified against the original application before committing.
Load ratings and application limits
The continuous output torque of 260 N.m (2301.2 lbf.in) at 100 rpm and 30 °C is the rating that governs steady-state operation. The maximum output torque of 416 N.m (3681.9 lbf.in) at the same speed and temperature is for intermittent peak loads — do not run continuously at this level. Maximum radial force on the output shaft is 1500 N for the 30,000-hour life target, applied at mid-distance from the shaft face. That drops to 2000 N if you accept a 10,000-hour service life. Maximum axial force is 2100 N for 30,000 hours, or 2800 N for 10,000 hours. The torsional rigidity figure of 13 N.m/arcmin tells you how much the gearbox winds up under load — 13 N.m of torque produces one arc-minute of angular deflection. This matters for positioning accuracy in indexing applications.
Noise and environmental fit
Noise level is 65 dB at 1 meter, no-load. That is a conversational-level sound — the gearbox will be audible in a quiet machine shop but not objectionable. The housing is black anodized aluminium, and the shaft material is C45 carbon steel. The gearbox is lubricated for life with no service interval, so it can be installed in a sealed enclosure or hard-to-access location without routine maintenance access.