We developed a custom solution for 8.H120.3554.1000, for heavy motor and generator systems where 1000 PPR push-pull feedback must stay stable under large hollow-shaft mounting, torque-arm restraint, M23 connector wiring, and EMC noise.

Model reading:

  • 3 = 100 mm torque arm
  • 5 = 25 mm through hollow shaft
  • 5 = push-pull with inverted signals, 10–30 VDC
  • 4 = radial M23 connector, 12-pin, reversed
  • 1000 = 1000 pulses per revolution

Typical production lead time: 15 working days.

At 1000 PPR, the encoder is not usually limited by pulse density first. The weak point normally appears at 25 mm shaft fit, torque-arm geometry, connector shielding, grounding continuity, or counter edge recognition.

Where the System Fails First

The 25 mm through hollow shaft gives easier mounting on large motor shafts, but it also makes concentricity and clamp stability critical. If the shaft fit is loose or the torque arm is forced, the encoder will show A/B phase jitter before the bearing shows visible damage.

The M23 connector improves serviceability compared with fixed cable, but it adds one more failure point: connector shielding. Once the shield path becomes unstable at the connector shell, the output may still switch, but the counter no longer sees clean edge timing. The H120 platform supports 300 kHz pulse frequency, while standard push-pull cable guidance is rated up to 150 m at 80 kHz.

Typical failure points:

  • Loose 25 mm hollow-shaft fit → phase jitter
  • Forced torque arm → housing oscillation
  • Poor M23 shield contact → unstable A/B/0 edges
  • Grounding error → reference pulse noise
  • Counter filtering mismatch → false counts
  • Shaft current without isolation control → feedback damage risk

Mechanical Boundary

H120 is built for heavy machines: 2.5 kV bearing isolation, HD-Safety-Lock™, dual shaft protection, IP67, seawater-resistant housing, 475 N radial load, 375 N axial load, and -40 °C to +100 °C operation. These margins are strong, but they cannot correct poor hollow-shaft fit or bad connector grounding.

Installation Notes

  • Keep the model format as 8.H120.3554.1000
  • Control the 25 mm through hollow shaft fit before checking electronics
  • Install the 100 mm torque arm without side-loading the housing
  • Verify M23 connector shield continuity
  • Separate encoder wiring from inverter and motor power cables
  • Confirm counter settings at real RPM and 1000 PPR
  • Check shaft-current isolation before replacing the encoder

Key Data

  • Model: 8.H120.3554.1000
  • Type: Heavy-duty through hollow shaft incremental encoder
  • Resolution: 1000 PPR
  • Output: Push-pull with inverted signals
  • Supply voltage: 10–30 VDC
  • Max frequency: 300 kHz
  • Max cable length: 150 m at 80 kHz
  • Shaft: 25 mm through hollow shaft
  • Mounting: 100 mm torque arm
  • Connection: Radial M23 connector, 12-pin, reversed
  • 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