Planetary gearbox, 160 mm frame, 40:1 reduction
The GBX1600400704F is a straight-tooth planetary gearbox from Schneider Electric's GBX series, with a 160 mm outer diameter and a 40:1 reduction ratio. It delivers a continuous output torque of 700 N.m at 100 rpm and a maximum torque of 1120 N.m under the same conditions — the number that governs sizing for a servo or stepper-driven axis. Rated service life is 30,000 hours at 100 rpm and 30 °C ambient, with the gearbox lubricated for life — no oil changes, no maintenance schedule beyond the bearing check at the motor end. The housing is black anodized aluminium, the output shaft is C45 steel.
Torque, backlash, and force limits — what they mean for fit
Maximum torsional backlash is 10 arc-minutes — this is the lost motion at the output when the input reverses direction. For a positioning axis that needs better than 0.1° repeatability at the load, that backlash has to be accounted for in the controller's reversal compensation or the axis will overshoot on direction changes. Torsional rigidity is 41 N.m/arcmin — a measure of how much the gearbox winds up under load. At the continuous torque of 700 N.m, the wind-up is about 17 arc-minutes (700 ÷ 41). That's elastic deflection, not backlash; the controller can't compensate for it unless the load torque is known and the stiffness is in the servo tuning model. Maximum radial force on the output shaft is 4200 N at mid-shaft for the 30,000-hour life, or 6000 N for a 10,000-hour duty cycle. Axial force limits are 6000 N and 8000 N respectively. These numbers decide whether the gearbox can handle a belt-drive or pinion load without overloading the output bearings — a belt tension that exceeds 4200 N radial will shorten life below the 30,000-hour rating. Efficiency is 94 % at rated load — typical for a single-stage planetary with straight teeth. The noise level is 70 dB at 1 m, no-load, which is moderate for a 160 mm frame; in a quiet lab environment you'll hear it, but on a production floor it's below ambient.
Obsolete — sourced through independent channels
Schneider Electric lists the GBX1600400704F as obsolete. The part is available through independent surplus and broker channels — quantities are lot-specific and confirmed at RFQ. For a line-down replacement, the key dimensions to match are the 160 mm housing diameter, the 40:1 ratio, and the output shaft interface. The continuous torque of 700 N.m and the 10 arc-min backlash set the performance floor for any substitute. No pin-compatible direct cross-reference exists in the current Schneider catalog — a mechanical adaptation may be needed.