--- title: "Leaderdrive LHD series hollow-shaft reducer specs" description: "Leaderdrive LHD ultra-flat hollow-shaft strain-wave reducer family for constrained axial packaging, with direct or supported hollow-input variants." canonical: https://actuatorlist.com/actuators/leaderdrive-lhd last-updated: 2026-11-01T14:05:43.000Z --- # LHD series (hollow-shaft harmonic reducer) by Leaderdrive (Suzhou Leader Harmonic Drive) > Leaderdrive LHD ultra-flat hollow-shaft strain-wave reducer family for constrained axial packaging, with direct or supported hollow-input variants. ## Specifications | Spec | Value | | --- | --- | | Category | Harmonic / Precision | | Peak torque | n/a: Family-level catalog value; confirm frame, ratio and variant. Reducer/sensor assembly, not an integrated motor and drive. | | Rated torque | n/a: Family-level catalog value; confirm frame, ratio and variant. Reducer/sensor assembly, not an integrated motor and drive. | | Max speed | n/a: Family-level catalog value; confirm frame, ratio and variant. Reducer/sensor assembly, not an integrated motor and drive. | | Gear ratio | 50:1-160:1: Family-level catalog value; confirm frame, ratio and variant. Reducer/sensor assembly, not an integrated motor and drive. | | Weight | n/a: Family-level catalog value; confirm frame, ratio and variant. Reducer/sensor assembly, not an integrated motor and drive. | | Torque density | n/a: Family-level catalog value; confirm frame, ratio and variant. Reducer/sensor assembly, not an integrated motor and drive. | | Price | quote only: Family-level catalog value; confirm frame, ratio and variant. Reducer/sensor assembly, not an integrated motor and drive. | | Price per Nm | n/a: Family-level catalog value; confirm frame, ratio and variant. Reducer/sensor assembly, not an integrated motor and drive. | | Backdrivable | Legacy catalog placeholder; not a measured family rating. See engineering notes. | | Backlash | Legacy catalog placeholder; not a measured family rating. See engineering notes. | | Voltage | n/a: Family-level catalog value; confirm frame, ratio and variant. Reducer/sensor assembly, not an integrated motor and drive. | | Peak current | n/a: Family-level catalog value; confirm frame, ratio and variant. Reducer/sensor assembly, not an integrated motor and drive. | | Communication | n/a | | Control modes | n/a | | Encoder | Legacy catalog placeholder; not a measured family rating. See engineering notes. | | Integrated driver | no | | Availability | in production | | Data status | Family-level evidence: confirm variant | ## Use cases - robot arm - industrial robot joint ## Engineering notes Family-level evidence reviewed October 1, 2026. Manufacturer-published data is not independent bench validation. Examples below are not selected inventory SKUs; existing catalog fields are not replaced with family ranges. ### Manufacturer specifications LHD prioritizes axial packaging. LHD-I uses direct input; LHD-III adds a supported, sealed hollow input for routing. The manufacturer's approximate 50% axial-length reduction versus LHS/LHSG is not a matched-SKU dimensional result. [Leaderdrive LHD, overview and Models](https://www.leaderdrive.com/product/2.html). ### Conditions and revision conflicts For frame 20, ratio 100, the [website table](https://www.leaderdrive.com/product/2.html) lists rated 28 Nm, start-stop 57 Nm, average 34 Nm, peak 95 Nm, maximum input 6,500 rpm and backlash ≤10 arcsec. The [LHD-I manual, PDF page 2 in ZIP](https://www.leaderdrive.com/uploadfile/file/20250725/1753420859665519.zip) lists 27 Nm at 2,000 rpm, start-stop 54 Nm, average 32 Nm, momentary 90 Nm, maximum input 6,000 rpm and backlash ≤20 arcsec. Website zero-backlash prose conflicts with its numerical table. These are unresolved source/revision differences, not a basis for choosing the more favorable limit. ### Engineering inference The [LHD geometry archive](https://www.leaderdrive.com/uploadfile/file/20250728/1753663504620515.zip) contains STEP and Parasolid files. Select the variant drawing before assigning mass, bore or envelope. Geometry is not a validated simulator package. Inference assumes the selected drawing and applicable revision are confirmed. Confidence in model completeness is low; no numerical efficiency, cooldown or precision estimate is defensible from this evidence. ### Unknown / confirmation required Numerical product-specific efficiency, cooling hardware, repeated thermal duty/derating, externally measured loaded output repeatability and calibrated simulation support remain unconfirmed in the reviewed material. Unknown is not zero. Encoder or sensor resolution is not output accuracy. Motor voltage, current and motor constants are not applicable to a reducer alone; select a motor/drive separately. Use the [robot actuator selection guide](/guides/robot-actuator-selection) to define the missing measurements and acceptance criteria. ## Sources - [https://www.leaderdrive.com/product/2.html](https://www.leaderdrive.com/product/2.html) - [https://www.leaderdrive.com/uploadfile/file/20250725/1753420859665519.zip](https://www.leaderdrive.com/uploadfile/file/20250725/1753420859665519.zip) - [https://www.leaderdrive.com/uploadfile/file/20250728/1753663504620515.zip](https://www.leaderdrive.com/uploadfile/file/20250728/1753663504620515.zip) - [https://www.gigager.net/showroom/leaderdrive-lhd-series-harmonic-drive-speed-reducer-for-robot-arms.html](https://www.gigager.net/showroom/leaderdrive-lhd-series-harmonic-drive-speed-reducer-for-robot-arms.html) - [https://leaderdrivereducer.en.ec21.com/LeaderDrive\_LHD\_Series\_Harmonic\_Drive--9782640\_9782690.html](https://leaderdrivereducer.en.ec21.com/LeaderDrive_LHD_Series_Harmonic_Drive--9782640_9782690.html) - [https://www.directindustry.com/prod/leader-harmonious-drive-systems-co-ltd/product-245080-2758185.html](https://www.directindustry.com/prod/leader-harmonious-drive-systems-co-ltd/product-245080-2758185.html) ## Similar Harmonic / Precision actuators - [EC-A5013-H17-100 (ENCOS)](https://actuatorlist.com/actuators/encos-ec-a5013-h17-100): 142.9 Nm/kg - [EC-A3814-H14-107 (ENCOS)](https://actuatorlist.com/actuators/encos-ec-a3814-h14-107): 138.2 Nm/kg - [LPA-20 (Low Profile Rotary Actuator) (Harmonic Drive LLC)](https://actuatorlist.com/actuators/harmonic-drive-lpa-20): 40.7 Nm/kg - [FHA-14C-100 (FHA-C Mini) (Harmonic Drive LLC)](https://actuatorlist.com/actuators/harmonic-drive-fha-14c-100): 17 Nm/kg - [SHA-CG series (SHA-CG Hollow Shaft Actuator) (Harmonic Drive LLC)](https://actuatorlist.com/actuators/harmonic-drive-sha-cg): n/a ## Machine-readable - JSON: https://actuatorlist.com/api/v1/actuators/leaderdrive-lhd - Catalog index for agents: https://actuatorlist.com/llms.txt