Rated torque, speed range, and what they tell you about the load
The HG-SR102B: Rated torque is 4.8 N·m at 2000 r/min, with a maximum torque of 14.3 N·m for acceleration and deceleration transients — a 3:1 peak-to-rated ratio that handles aggressive move profiles without oversizing the motor frame. The speed range spans 2000 r/min rated to 3000 r/min maximum, with an instantaneous allowable speed of 3450 r/min before the overspeed trip threshold. The 1.0 kW continuous rating sets the thermal ceiling for sustained duty; the 16.5 kW/s power rate at rated torque tells you how fast it can deliver energy to the load — useful for sizing the acceleration phase of a cycle.
Encoder resolution and inertia matching — the loop-tuning constraints
The 22-bit absolute incremental encoder delivers 4,194,304 pulses per revolution — enough resolution for sub-arcminute positioning without a separate external encoder. The absolute position is retained on power loss, so homing sequences can be eliminated on machines that stay within the travel range. Recommended load-to-motor inertia ratio is 17 times or less. Exceed that and the velocity loop starts to feel sluggish; the auto-tuning in the MR-J4 series can compensate up to about 10×, but above 17× you are looking at a mechanical redesign or a larger frame. Moment of inertia of the rotor alone is 13.8 × 10⁻⁴ kg·m² — plug that into your load calculation before committing the axis.
IP67 enclosure and the oil-seal decision
The motor is all-enclosed self-cooled with an IP67 rating — the housing and connector seal keep out dust and washdown water. This is the standard build without an oil seal; a variant with an oil seal (HG-SR_J suffix) is available if the motor is mounted shaft-up in a gearbox-oil-mist environment. For most direct-coupled or belt-driven applications the standard IP67 build is sufficient. Axial load capacity is 490 N, radial load 980 N — these are the bearing limits at the shaft centre. A belt-drive with high belt tension will eat into the radial budget; keep the resultant load below 980 N to avoid premature bearing noise or seizure.
Environmental limits and installation conditions
Operating ambient temperature is 0 °C to 40 °C, non-condensing humidity up to 80% RH. Storage range is -15 °C to 70 °C at up to 90% RH. The motor is rated for indoor use only — no direct sunlight, no corrosive gas, flammable gas, oil mist, or conductive dust. Elevation limit is 2000 m above sea level; above that, derate the output or force-cool the enclosure.
Sourcing and compliance documentation
The HG-SR102B is quoted to order against the BOM quantity. Compliance with international standards is declared per Mitsubishi's Standards Compliant page; the motor carries the CE, UL, and RoHS markings typical of the HG-SR series. The order code is the same as the product number — no variant suffix to confuse.