BLDC motor 70ZWC20X-1

48 Vframeless20-pole

Product description
The 70mm frameless BLDC motor features a modular stator and rotor architecture and optimized slot ratios to increase torque density. The rotor provides a large internal bore for driveline or shaft integration, while the stator is intended for embedded installation by the customer to enable custom mounting structures and cooling solutions. The slot-pole combination reduces cogging torque to support smooth rotation. The assembly is compact and highly integrated.

Motor characteristics
Motor part number — 70ZWC20X-1 | 70ZWC25X-1
Stator outer diameter — 69±0.037 | 69±0.037
Rotor inner diameter — 42+0.039 | 42+0.039
Overall length (L) — 15.9 mm | 21.5 mm
Stack length (L1) — 10.3 mm | 15.9 mm
Rotor length (L2) — 20.5±0.2 mm | 26±0.2 mm
Number of slots — 18 | 18
Pole pairs — 10 | 10
Phase-to-phase resistance (Ω) — 0.32 | 0.22
Phase-to-phase inductance (mH) — 0.52 | 0.35
Winding connection method — Star connection | Star connection
Insulation class — F | F
Duty type — S2 | S2
Feedback method — Hall sensor | Hall sensor
Commutation angle — 120° | 120°
Insulation strength (Withstand voltage) — 500VAC/1mA/1s | 500VAC/1mA/1s
Insulation resistance — 100MΩ/500VDC | 100MΩ/500VDC
Stator weight (g) — 167.5 | 224
Rotor weight (g) — 72 | 90
No-load speed (RPM) — 4350 | 4400
No-load current (A) — 0.5 (REF) | 1.3 (REF)
Rated voltage (VDC) — 48 | 48
Rated power (W) — 216 | 456
Rated torque (N·m) — 0.55 | 1.3
Rated speed (RPM) — 3750 | 3350
Rated current (A) — 5.4 | 11.4
Torque constant (Nm/A) — 0.109 | 0.13
Back-EMF constant (Vrms/Krpm) — 8.1 | 9.6
Peak torque (N·m) — 1.65 | 2.6
Peak current (A) — 14.2 | 21
Rotor inertia (g·cm²) — 358 | 455

Dimensional & wiring notes
Dimensional drawings and lead-out/wire color diagrams are provided for variants 70ZWC20X-1 and 70ZWC25X-1. Typical lead-out examples: UL1332 AWG20 (yellow/red/black for U/V/W) and UL1332 AWG18 (yellow/red/black for U/V/W). Verify connector and lead length requirements for your embedded installation.

Technical specifications

• Model variants: 70ZWC20X-1, 70ZWC25X-1
• Stator outer diameter: 69±0.037 mm
• Rotor inner diameter: 42+0.039 mm
• Overall length (L): 15.9 mm (70ZWC20X-1) / 21.5 mm (70ZWC25X-1)
• Stack length (L1): 10.3 mm / 15.9 mm
• Rotor length (L2): 20.5±0.2 mm / 26±0.2 mm
• Number of slots: 18
• Pole pairs: 10
• Phase-to-phase resistance: 0.32 Ω / 0.22 Ω
• Phase-to-phase inductance: 0.52 mH / 0.35 mH
• Winding connection: Star
• Insulation class: F
• Duty type: S2
• Feedback: Hall sensor
• Commutation angle: 120°
• Rated voltage: 48 VDC
• Rated power: 216 W / 456 W
• Rated torque: 0.55 N·m / 1.3 N·m
• Rated speed: 3750 RPM / 3350 RPM
• Rated current: 5.4 A / 11.4 A
• Peak torque: 1.65 N·m / 2.6 N·m
• Peak current: 14.2 A / 21 A
• Rotor inertia: 358 g·cm² / 455 g·cm²