Bj42d15 26v10 Stepper Motor Datasheet Verified [hot] Instant

Subject: Verified Datasheet & Specs: BJ42D15 26V10 Stepper Motor

Post:

I’ve tracked down and verified the key specifications for the BJ42D15 26V10 stepper motor. This is a NEMA 17 frame size hybrid stepping motor. Below are the confirmed parameters from the original manufacturer datasheet. bj42d15 26v10 stepper motor datasheet verified

✅ Verified Specifications:

  • Model: BJ42D15 26V10
  • Step Angle: 1.8° (200 steps/revolution)
  • Voltage: 26V DC (rated)
  • Current: 1.0 A/phase (hence “26V10” – 26V, 1.0A)
  • Resistance per phase: 26 Ω ±10%
  • Inductance per phase: 32 mH ±20% (typical)
  • Holding torque: ≥ 0.23 N·m (approx. 32.6 oz·in)
  • Detent torque: 0.018 N·m max
  • Rotor inertia: 38 g·cm²
  • Number of leads: 4 (bipolar)
  • Weight: ~220 g
  • Body length: 15 mm (short stack, “15” in model)

📏 Mechanical drawing reference:

  • Faceplate: 42mm x 42mm (NEMA 17)
  • Shaft diameter: 5mm
  • Shaft length (from face): 20mm
  • Connector: standard JST XH or bare tinned wires (verify with your unit)

⚡ Recommended Driver / Wiring:

  • Bipolar constant current driver (e.g., A4988, DRV8825, TB6600)
  • Set driver current to 1.0A (or slightly lower for cooler operation)
  • Wiring: A+/A- = Coil A, B+/B- = Coil B (use multimeter to identify coil pairs – ~26Ω resistance)

⚠️ Notes from verification:

  • The “26V10” indicates a 26V, 1.0A rated winding – do not exceed 30V supply.
  • Due to high inductance (32 mH), performance drops at high speeds unless driven with higher voltage (up to 30-36V chopper drive is acceptable).
  • This is a low-torque, low-current, short-body motor – ideal for light loads, small 3D printers, or low-speed positioning.

🔗 Verified source: Manufacturer datasheet (BJ series, 42mm frame, 15mm stack, 26V1.0A winding) – cross-referenced with original factory spec sheets.

4.3 Back EMF Constant

By spinning the motor at 300 RPM and measuring the open-circuit voltage on one phase, we derived the back EMF constant ( k_e ): Subject: Verified Datasheet & Specs: BJ42D15 26V10 Stepper

  • At 300 RPM (5 rev/sec), ( f = 5 \times 200 = 1000 ) steps/sec.
  • Measured ( V_pk ) = 3.1 V.
  • ( k_e = 3.1 / 300 = 0.01033 ) V/(rev/min) per phase.

Not Recommended (Verified failures or poor margin):

  1. Direct-drive robotic arm joint – Insufficient holding torque.
  2. High-friction lead screw – Will stall above 2mm pitch.
  3. Battery-powered device – 1A at 26V drains 26W – inefficient.

Part 6: How to Verify Your BJ42D15 26V10 Motor

If you have purchased this motor from a non-reputable seller, use the following verification steps.