120 mm planetary gearbox, 8:1 reduction, 120 N.m continuous
The GBX1200080553F is a Schneider Electric planetary gearbox with a 120 mm outer diameter and an 8:1 reduction ratio. It delivers a continuous output torque of 120 N.m (1062.09 lbf.in) at 100 rpm and 86 °F (30 °C), with a maximum output torque of 192 N.m (1699.3 lbf.in) under the same conditions. The straight-tooth design and 8 arc.min maximum torsional backlash make this a precision-grade gearbox for positioning applications where repeatable accuracy matters. Torsional rigidity is 12 N.m/arcmin, so the output shaft resists windup under load — critical for servo-driven indexing or pick-and-place axes.
Torque, life, and load ratings — what they mean for fit
The continuous torque rating of 120 N.m at 100 rpm is the design point for a 30,000-hour service life. If the application cycles above 100 rpm or runs at higher ambient temperatures, the actual service life shortens — the 30,000-hour figure assumes 100 rpm and 86 °F (30 °C). The gearbox is lubricated for life, so no maintenance schedule for oil changes. Maximum axial force (Fa) is 2100 N at 100 rpm for the 30,000-hour target, or 2800 N if the application accepts a 10,000-hour life. Maximum radial force (Fr) is 1500 N at 100 rpm for 30,000 hours, or 2000 N for 10,000 hours, with the force applied at mid-distance from the output shaft. These are the limits for overhung loads from pulleys, sprockets, or direct-mounted couplings. Efficiency is 94 %, which means 6 % of the input power is lost as heat inside the housing. For a 120 N.m output at 100 rpm (~1.26 kW output), the heat loss is about 80 W — the black anodized aluminium housing dissipates this without forced cooling in most panel or machine-frame mounts. Noise level is 65 dB at 1 m, no-load — quiet enough for indoor production lines without acoustic enclosures.
Obsolete — sourcing through independent channels
Schneider Electric lists the GBX1200080553F as Obsolete. The part is available through independent surplus and broker channels — quantities are lot-specific and confirmed at RFQ. No pin-compatible drop-in replacement from the same family is documented, so a substitution may require a mechanical re-design of the mounting interface and shaft coupling. The shaft output carries an IP54 rating, meaning it resists dust ingress and splashing water — adequate for most factory-floor environments but not for washdown zones. The shaft is C45 steel; the housing is black anodized aluminium.