The GBX1200800551F is a straight-tooth planetary gearbox from Schneider Electric's GBX series, sized for a 120 mm housing diameter and an 80:1 reduction ratio. That ratio is the headline number for a speed-reduction spec: an input of 8000 rpm delivers 100 rpm at the output shaft, multiplying torque by roughly the ratio minus efficiency losses. Continuous output torque is 260 N.m at 100 rpm and 30 °C, with a maximum intermittent torque of 416 N.m under the same conditions. For a motion axis driving a constant load — conveyor, indexing table, rotary actuator — the continuous figure governs thermal steady-state; the maximum figure covers acceleration and emergency stops within the 30000-hour service life. Efficiency is listed at 94 %, which is typical for a single-stage planetary with straight teeth. The 6 % loss shows up as heat in the lubricant; the gearbox is lubricated for life, so no maintenance interval for oil changes applies.
Mechanical interface — shaft loads, backlash, and environmental sealing
The output shaft is C45 steel, and the housing is black anodized aluminium. Maximum radial force Fr is 1500 N at 100 rpm for the 30000-hour life, applied at mid-distance on the output shaft; axial force Fa is 2100 N under the same duty. These are the limits for belt-pulley or chain-sprocket overhung loads — exceeding them shortens bearing life faster than the torque rating. Torsional backlash is maximum 14 arc-minutes, and torsional rigidity is 12 N.m/arcmin. For a positioning axis that reverses direction, the 14 arc-minutes of lost motion must be accounted for in the servo tuning or compensated in the controller; a lower-backlash gearbox would be needed for high-precision indexing. The shaft output seal carries an IP54 rating — protection against dust ingress and splashing water, but not immersion or high-pressure washdown. Ambient operating range is -25 to 90 °C, which covers most indoor industrial environments but not freezer or oven applications without derating.
Lifecycle status — obsolete, sourced through independent channels
Schneider Electric lists this gearbox as obsolete. Sourcing runs through independent distribution — quantities are confirmed at RFQ against the BOM line, and the landed cost includes the premium for a discontinued part with no direct drop-in replacement. The 94 % efficiency, 80:1 ratio, and 120 mm frame size define the mechanical envelope. If a replacement is needed, the search should match these three parameters plus the output shaft diameter and keyway dimensions — a parametric cross-reference, not a pin-compatible swap.