Planetary gearbox, 3:1 reduction, 115 N.m continuous — what the ratings mean
The GBX1200030704F is a straight-tooth planetary gearbox from Schneider Electric's GBX series, sized for a 120 mm outer diameter and a 3:1 reduction ratio. The continuous output torque is 115 N.m at 100 rpm and 30 °C, with a maximum intermittent torque of 184 N.m under the same conditions — the gap between continuous and peak tells you the thermal margin for short overloads during acceleration or reversing cycles. Rated service life is 30,000 hours at 100 rpm and 30 °C, which is roughly 3.4 years of continuous operation at that speed. The gearbox is lubricated for life, so no field maintenance on the oil — the housing is sealed at the factory. Efficiency is listed at 94 %, meaning about 6 % of input power is lost to friction and churning losses in the gear mesh. For a 115 N.m output at 100 rpm, that's roughly 1.2 kW input to deliver 1.13 kW at the shaft — the heat rejection is modest but needs to be considered in a sealed enclosure.
Mechanical limits — axial and radial load capacity
Maximum axial force (Fa) is 2100 N at 100 rpm for the full 30,000-hour service life, or 2800 N if you accept a shorter 10,000-hour life. Radial force (Fr) applied at mid-span on the output shaft is 1500 N for 30,000 hours, or 2000 N for 10,000 hours. These are the bearing limits — exceeding them shortens life non-linearly. Torsional rigidity is 12 N.m per arcminute of wind-up, and maximum torsional backlash is 8 arcminutes. For positioning applications, that backlash is the lost motion between input and output when reversing direction — 8 arcmin at the output translates to roughly 0.13° of positioning uncertainty before the load picks up. The shaft output seal is rated IP54, meaning dust-protected and splash-resistant — fine for most industrial environments but not for washdown or submerged service. Ambient operating range is -25 to 90 °C, which covers most indoor factory conditions without derating.
Lifecycle status — obsolete, sourced through independent channels
Schneider Electric has marked the GBX1200030704F as obsolete. No official successor or cross-reference is recorded from the manufacturer — the GBX series has been superseded by newer planetary gearbox families with different mounting interfaces and ratios. Available through independent surplus and broker channels. Quantities are lot-specific and confirmed at RFQ. The gearbox is a mechanical component with no firmware or electronics — condition is visual and dimensional, so a used or NOS unit is typically serviceable if the seals and bearings check out. No pin-compatible direct replacement exists from Schneider Electric's current catalog. A functional replacement would require matching the 120 mm housing diameter, 3:1 ratio, 115 N.m continuous torque, and the output shaft dimensions — expect a different bolt pattern or keyway, meaning a mounting plate adapter.