We developed a custom solution for 8.H120.3561.2048, for heavy motor and generator systems where 2048 PPR power push-pull feedback must stay stable under large hollow-shaft mounting, torque-arm restraint, cable routing, and EMC noise.

Model reading:

  • 3 = 100 mm torque arm
  • 5 = 25 mm through hollow shaft
  • 6 = power push-pull with inverted signals, 10–30 VDC
  • 1 = radial PVC cable, 1 m
  • 2048 = 2048 pulses per revolution

Typical production lead time: 15 working days.

At 2048 PPR, the first weak point is usually split between counter margin and shaft fit. The output stage is stronger than standard push-pull, but it does not remove the need for shielding, grounding, and clean counter input.

Where the System Fails First

The 25 mm through hollow shaft must stay concentric. If the shaft fit is loose or the torque arm is forced, the encoder normally shows A/B phase jitter before any visible bearing damage.

For the power push-pull version, the datasheet gives 350 m maximum cable length at 100 kHz, compared with shorter limits for standard push-pull. This improves long-distance tolerance, but the real field failure still appears at shield termination, cabinet grounding, or inverter-side EMC injection.

Typical failure points:

  • Loose 25 mm shaft fit → phase jitter
  • Forced 100 mm torque arm → housing oscillation
  • Poor shield grounding → unstable A/B/0 edges
  • Counter margin too low → missed pulses
  • Ground loop → reference signal noise
  • Shaft current without isolation control → feedback damage risk

Mechanical Boundary

H120 is built for heavy machines: 2.5 kV bearing isolation, HD-Safety-Lock™, double shaft protection, IP67, seawater-resistant housing, 475 N radial load, 375 N axial load, and -40 °C to +100 °C operation. These margins only work when the shaft fit, torque arm, and grounding path are controlled.

Installation Notes

  • Keep the model format as 8.H120.3561.2048
  • Control the 25 mm through hollow shaft fit before checking electronics
  • Install the 100 mm torque arm without side-loading the housing
  • Keep cable shielding continuous from encoder to cabinet
  • Separate encoder wiring from inverter and motor power cables
  • Confirm counter capacity at real RPM and 2048 PPR
  • Check shaft-current isolation before replacing the encoder

Key Data

  • Model: 8.H120.3561.2048
  • Type: Heavy-duty through hollow shaft incremental encoder
  • Resolution: 2048 PPR
  • Output: Power push-pull with inverted signals
  • Supply voltage: 10–30 VDC
  • Max frequency: 300 kHz
  • Max cable length: 350 m at 100 kHz
  • Shaft: 25 mm through hollow shaft
  • Mounting: 100 mm torque arm
  • Connection: 1 m radial PVC cable
  • Protection: IP67
  • Temperature: -40 °C to +100 °C
  • Shaft load: 475 N radial / 375 N axial
  • Shock: 2000 m/s², 6 ms
  • Vibration: 150 m/s², 10–2000 Hz