We developed a custom solution for 8.H120.335A.1024.0030, for heavy motor and generator systems where 1024 PPR push-pull feedback must stay stable under 20 mm through-shaft mounting, torque-arm restraint, 3 m cable routing, and shaft-current risk.

Model reading:

  • 3 = 100 mm torque arm
  • 3 = 20 mm through hollow shaft
  • 5 = push-pull with inverted signals, 10–30 VDC
  • A = radial PVC cable, special length
  • 1024 = 1024 pulses per revolution
  • 0030 = 3 m cable length

Typical production lead time: 15 working days.

At 1024 PPR, the counter load is usually manageable. The first weak point is more often shaft concentricity, torque-arm geometry, cable shielding, and grounding continuity.

Where the System Fails First

The 20 mm through hollow shaft must stay concentric with the motor shaft. A loose fit or shaft runout usually appears first as A/B phase jitter, not as visible encoder damage.

The 3 m radial cable is short, so cable length is not the main limit. The real issue is routing. If the cable runs near inverter output lines or the shield is interrupted at the cabinet, the PLC may still see voltage changes, but the edge timing is no longer reliable. Standard push-pull transmission is rated up to 150 m at 80 kHz, assuming correct shielding and grounding.

Typical failure points:

  • Loose 20 mm shaft fit → A/B phase jitter
  • Forced 100 mm torque arm → housing oscillation
  • Poor cable shielding → unstable pulse edges
  • Grounding error → reference signal noise
  • Counter filtering mismatch → false counts
  • Shaft current without isolation control → feedback damage risk

Mechanical Boundary

H120 provides 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 help when shaft fit, torque-arm installation, and cable shielding are controlled.

Installation Notes

  • Keep the model format as 8.H120.335A.1024.0030
  • Check the 20 mm through hollow shaft fit before checking electronics
  • Install the 100 mm torque arm without side-loading the housing
  • Route the 3 m cable away from inverter and motor power wiring
  • Keep shielding continuous from encoder to cabinet
  • Confirm counter settings at real RPM and 1024 PPR
  • Check shaft-current isolation before replacing the encoder

Key Data

  • Model: 8.H120.335A.1024.0030
  • Type: Heavy-duty through hollow shaft incremental encoder
  • Resolution: 1024 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: 20 mm through hollow shaft
  • Mounting: 100 mm torque arm
  • Connection: 3 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