60:1 planetary reduction for motion control
The GBX1200601002F is a straight-tooth planetary gearbox from Schneider Electric's GBX series, delivering a 60:1 reduction ratio in a 120 mm diameter package. This ratio transforms a motor's high-speed, low-torque output into the higher torque at lower speed that indexing tables, conveyors, and positioning axes demand. Continuous output torque is rated 260 N.m at 100 rpm and 30 °C, with a maximum intermittent torque of 416 N.m under the same conditions — the margin between continuous and peak defines the duty cycle headroom for acceleration and emergency stops.
Torque, backlash, and stiffness — the fit triad
Efficiency at 94 % means 6 % of the transmitted power is lost as heat inside the gearbox. For a 260 N.m continuous load at 100 rpm (about 2.7 kW input), that's roughly 160 W of thermal dissipation that the aluminium housing must sink — a factor in enclosure ventilation if the gearbox is enclosed. Maximum torsional backlash is 14 arcmin, which sets the positioning repeatability floor in a reversing or servo application. For comparison, a precision planetary stage might spec 5–8 arcmin; this gearbox sits in the standard industrial class where absolute positioning is handled by the downstream encoder, not the gear train. Torsional rigidity of 12 N.m/arcmin quantifies how much the gear train winds up under load — at the 260 N.m continuous torque, the wind-up is about 22 arcmin. This matters for servo tuning: the effective spring constant between motor and load shifts the resonance frequency.
Sourcing an obsolete planetary gearbox
Schneider Electric has marked the GBX1200601002F as obsolete. Stock is sourced through independent surplus and broker channels. No pin-compatible direct replacement exists from Schneider — a functional equivalent would need a parametric match on the 60:1 ratio, 120 mm flange, and 260 N.m continuous torque.
Mechanical interface and environmental limits
The housing is black anodized aluminium with a 120 mm external diameter. Shaft material is C45 carbon steel. The shaft output seal carries an IP54 rating — splash-resistant but not submersible; suitable for indoor machine builds where washdown is not directed at the shaft exit. The gearbox is lubricated for life, eliminating maintenance intervals for oil changes. Maximum axial force (Fa) is 2100 N for the 30000-hour service life, rising to 2800 N for a 10000-hour life. Radial force (Fr) limits are 1500 N and 2000 N respectively, applied at mid-span of the output shaft. These bearing-load limits govern overhung pulley or sprocket placement.