Calculate ratio, service-factor torque, current draw, and engineering risk for 48V BLDC or brushed DC gearmotor concepts before requesting an OEM sample.
This also covers searches for a 48v motor with gearbox, 48v dc motor gearbox, or 48 volt electric gearmotor, with the comparison centered on 48V vs 24V current, gearmotor selection, and thermal risk.
Use the calculator for the first-pass numeric screen, then use this report layer to decide what must be validated before purchasing or releasing a sample.
The tool uses deliberately conservative screening assumptions. Replace these values with motor and gearbox datasheet numbers before issuing a production RFQ.
| Input Or Formula | Value Used | Decision Limit |
|---|---|---|
| Base motor speed | 3000 rpm | Screening assumption for compact 48V BLDC/DC motors. Replace with your motor datasheet before sampling. |
| Reduction ratio | motor rpm / target output rpm | Flags ratios above 100:1 when paired with worm gearing. |
| Output torque | (kW x 9550 / output rpm) x gearbox efficiency | Uses output speed and reducer efficiency; startup and stall torque are not included. |
| Service-factor rating | output torque x duty factor | Light 1.0, moderate 1.25, heavy 1.5. |
| Current estimate | motor W / (48V x 0.85) | Electrical screening only. Battery sag, driver limit, and motor efficiency curve can change this value. |
Claims with date-sensitive or standards-sensitive implications are separated from AMR Gearbox recommendations so the decision chain can be audited.
| Claim Area | How It Affects Selection | Traceable Source |
|---|---|---|
| Current and I2R loss | Use 48V when a 24V design would force large cables, hot connectors, or a controller near its current ceiling. | Vicor, Why are Power Designs Moving to 48V? white paper; 48V power distribution overview. Checked 2026-07-18 |
| Lithium-ion voltage window | Check controller undervoltage and top-speed margin against pack voltage under load, not only nominal 48V. | Battery University BU-303 on nominal Li-ion voltage and voltage naming. Checked 2026-07-18 |
| Worm gearbox thermal risk | Treat high-ratio worm gearboxes as conditional for continuous 48V duty unless thermal capacity is proven. | KHK Gear Manufacturer notes typical cylindrical worm gear efficiency around 30-60%. Checked 2026-07-18 |
| 60Vdc safety threshold context | Do not state blanket SELV compliance; verify the applicable standard, max charged voltage, accessible energy, and enclosure. | PowerElectronicTips IEC 62368-1 overview summarizes ES1 voltage limits including 60Vdc. Checked 2026-07-18 |
The chart assumes the same mechanical power and 85% drive efficiency. It shows why current-driven hardware limits appear earlier in 24V systems.
The useful comparison is not just voltage. It is voltage plus duty cycle, gearbox heat, controller current, and integration constraints.
| Application | Power | Output Speed | Gearbox Pairing | Must Check |
|---|---|---|---|---|
| Heavy-payload AMR drive wheel | 1000-3000W | 50-250 rpm | Planetary or helical planetary | Peak current, brake, shaft load, IP rating |
| Logistics conveyor module | 500-1500W | 60-300 rpm | Helical inline or low-ratio worm | Continuous duty temperature and noise |
| Lift or indexing axis | 400-1200W | 10-120 rpm | Planetary plus brake, or worm with derating | Holding torque, backdrive risk, emergency stop |
| Light EV auxiliary drive | 500-2000W | 100-600 rpm | Compact planetary | Battery sag, controller limit, enclosure cooling |
The calculator screens a concept. It cannot replace motor efficiency curves, gearbox thermal tests, brake validation, or regional safety review.
Questions are grouped by sizing, electrical selection, and procurement readiness.
Send power, output speed, duty cycle, envelope, shaft load, controller limit, and annual volume. The calculator result gives the first pass; the RFQ should validate thermal and integration limits.
