EncoderWorks configures FGH4K-2000G-90G-NG/20P as a custom compatible replacement solution for heavy-duty incremental feedback where 2000 PPR scaling, A/B 90° quadrature, NG reference-pulse behavior, terminal-box wiring, shield continuity, and 20 mm hollow-shaft fit must remain stable at the installed counter. The failure boundary is not a fieldbus address or an absolute position word, but wrong pulse scaling, missed edges, phase jitter, reference-pulse mismatch, output-driver incompatibility, ground noise, hollow-shaft runout, and torque-reaction movement. Typical production lead time: 15 working days.
This model is used where the controller reads speed, direction, and relative position from A/B incremental channels and uses the NG reference pulse for indexing, homing, or machine synchronization. A compatible replacement must preserve the 2000 pulses per revolution, 90° channel separation, reference-pulse location, inverted reference requirement, output level, terminal assignment, shield path, 20P bore interface, and heavy-duty mechanical boundary.
System Limits
The first system boundary is the 2000 PPR counter interface. FGH4K-2000G-90G-NG/20P must be checked against the controller’s maximum input frequency, edge evaluation mode, expected A/B direction, reference-pulse width, output-driver type, cable length, supply level, and inverted-signal requirement. If the replacement is supplied as 1200 PPR, 2048 PPR, 1024 PPR, or another nearby resolution, the encoder may still generate clean pulses while the controller calculates the wrong speed, travel distance, or index position. At higher shaft speeds, 2000 PPR also increases edge rate, so insufficient counter margin can appear as missed counts, unstable speed feedback, one-direction drift, or reference-pulse detection failure.
The second boundary is the terminal-box and 20 mm hollow-shaft installation. Terminal-box wiring, 0 V reference, shield bonding, cable routing, housing ground, and cable-entry strain relief must be treated as part of the measurement circuit. A correct encoder can still fail if the cable shield is grounded through a high-impedance path, the signal cable is routed beside brake or inverter wiring, the terminal box loses PE continuity, or the 20 mm bore is clamped with eccentric load. Mechanical checks should include bore fit, shaft runout, axial movement, torque-reaction restraint, vibration, and bearing load.
Wiring & Installation
Before replacement, confirm the complete installed model code, 2000 PPR requirement, A/B phase relationship, NG reference-pulse use, inverted reference requirement, output circuit, supply voltage, maximum shaft speed, counter input frequency, terminal-box layout, cable entry direction, shield termination method, and 20 mm hollow-shaft dimension. This FGH4K version should not be inferred from FGH4KK dual-terminal variants because the grounding path, wiring layout, cable-entry count, and redundant-output expectation may be different.
During installation, verify A, B, reference, inverted reference if used, supply, 0 V, shield, and housing ground before powering the system. Keep signal cables away from motor, brake, SCR, and VFD wiring, and avoid using the cable shield as a load-carrying ground conductor. The hollow shaft must sit concentrically on the machine shaft, and the torque-reaction element should stop encoder-body rotation without forcing the bearing system. Eccentric preload can become phase jitter, bearing wear, or poor reference-pulse repeatability.
Custom Compatible Solution
- Match 2000 PPR incremental feedback, A/B 90° quadrature, NG reference-pulse behavior, and controller counter expectations
- Preserve output-driver compatibility, terminal-box wiring, supply reference, inverted-signal requirement, shield path, and grounding continuity
- Adapt the 20 mm hollow shaft, heavy-duty housing, bore fit, torque-reaction boundary, cable entry, and machine-side mounting geometry
- Review counter frequency margin, speed calculation, homing behavior, EMC exposure, shaft runout, vibration, and commissioning checks before shipment
Key Data
| Item | Data |
|---|---|
| Model | FGH4K-2000G-90G-NG/20P |
| Encoder type | Heavy-duty hollow-shaft incremental encoder |
| Feedback type | Incremental A/B with reference pulse |
| Pulse count | 2000 PPR |
| Phase relationship | A/B, 90° quadrature |
| Reference pulse | NG reference pulse with inverted signal requirement |
| Shaft interface | 20 mm hollow shaft / 20P bore |
| Connection boundary | Terminal-box wiring requires confirmation against installed version |
| Output circuit | Requires confirmation against controller input |
| Supply voltage | Requires confirmation against installed version |
| Key system checks | Counter frequency, speed scaling, edge evaluation, A/B direction, NG reference pulse, inverted signal, shield grounding |
| Key mechanical checks | Bore fit, shaft runout, torque reaction, axial movement, vibration, bearing load |
| Replacement focus | 2000 PPR scaling, counter frequency margin, NG reference behavior, terminal-box grounding, 20 mm hollow-shaft stability |
