Obsolete — what that means for procurement
Schneider Electric lists the GBX0400121003F as obsolete. This gearbox is sourced through independent surplus and broker channels.
12:1 ratio, 20 N.m — load capacity and duty
The GBX0400121003F is a 40 mm-diameter planetary gearbox with a 12:1 reduction ratio. Continuous output torque is 20 N.m at 100 rpm and 30 °C — this is the rated load for a 30000-hour service life under those conditions. Efficiency is 94 %, meaning about 6 % of input power is lost as heat in the gear train. That loss is already accounted for in the torque rating, but it matters for thermal budgeting in a confined enclosure. Maximum torsional backlash is 28 arcmin — this is the angular play between input and output when reversing direction. For positioning applications that need tighter repeatability, a lower-backlash gearbox would be needed.
Mounting, sealing, and environmental limits
The housing is black anodized aluminium with a 40 mm external diameter. Shaft output sealing is IP54 — splash-resistant but not submersible; suitable for indoor or sheltered installations where occasional moisture or dust is present. The gearbox is lubricated for life, so no periodic oil changes are required — the grease fill is sealed for the service interval. Maximum axial force on the output shaft is 200 N at 100 rpm; maximum radial force is 200 N at 100 rpm (force applied at mid-span). These limits drop to 160 N radial if targeting the full 30000-hour life. Exceeding these loads shortens bearing life.
Noise, stiffness, and shaft material
Noise level is 55 dB at 1 m, no-load — roughly the sound of a quiet office. Straight-cut teeth are inherently noisier than helical, but the 55 dB figure is low enough for most machine-tool and conveyor applications. Torsional rigidity is 1.1 N.m per arcmin — a measure of how much the gear train twists under load. Higher stiffness means less wind-up in servo or positioning axes. Shaft material is C45 carbon steel — a standard medium-carbon grade with good strength and wear resistance for general industrial use.