Question 1

What does KV rating mean for a drone motor?

Accepted Answer

KV is the motor's no-load RPM per volt of input. A 920 KV motor on a 24V battery spins at roughly 22,080 RPM unloaded. Lower KV motors (300-600 KV) swing larger propellers at lower RPM for heavy-lift and agricultural spray drones, producing more thrust per watt. Higher KV motors (900-2300 KV) suit racing and smaller drones that use smaller props at higher RPM. Matching KV to propeller diameter and pitch is critical for efficiency.

Question 2

How do I calculate thrust efficiency for motor selection?

Accepted Answer

Thrust efficiency is measured in grams of thrust per watt (g/W). Efficient agricultural and delivery drone motors achieve 8-12 g/W at hover throttle. To select a motor, calculate total hover thrust needed (total weight × 2 for a 2:1 thrust-to-weight ratio), divide by the number of motors, then choose a motor-propeller combination that delivers that thrust at 50-60% throttle. Operating at half throttle ensures headroom for maneuvering and maximizes battery endurance.

Question 3

How do I size a motor for payload capacity?

Accepted Answer

Add up frame weight, battery weight, payload weight and all accessories. The total maximum thrust of all motors should be at least 2× this all-up weight for stable flight, and 2.5-3× for agile maneuvering or gusty conditions. For a 25 kg agricultural spray drone, you need at least 50 kg total thrust — for example, 8 motors each producing 6.25 kg thrust. Select motors that hit this thrust at 50-65% throttle for thermal headroom and battery life.

Question 4

What ESC compatibility should I look for?

Accepted Answer

The ESC must match the motor's voltage range, maximum current draw and communication protocol. For multirotors, look for ESCs that support DShot600 or DShot1200 digital protocols for faster throttle response. The ESC current rating should be at least 20% above the motor's peak current. For agricultural drones, conformal-coated ESCs with active cooling handle sustained high-power spraying runs. Shenghe can supply matched motor-ESC kits tested together for optimal timing and efficiency.

Parameter	Range
Voltage	DC 12V / 24V / 48V (3S-12S LiPo)
Rated power	50 W — 2000 W
KV rating	100 — 2300 KV
Motor type	Outrunner (external rotor)
Weight	30 g — 450 g
Max thrust	0.5 kg — 12 kg per motor
Bearing	Dual-sealed ball bearings
Shaft	3 mm — 8 mm hardened steel

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