Problems We Solve · Drives & Motion
Encoder or feedback fault on a drive or axis?
Likely causes, what our technicians check onsite, and how to get it fixed — verified engineers across India, onsite in hours (under 4 in Hyderabad), 24/7.
01 / Overview
Encoder / Feedback Fault
Position and speed feedback is where a large share of drive and servo faults actually originate — a damaged cable, a failed encoder, a flat absolute-encoder battery or electrical noise. Because a feedback fault often presents as a drive alarm, the amplifier gets blamed and replaced when the real fault is a ₹2,000 cable.
We diagnose feedback faults across servo, spindle and drive systems — incremental and absolute encoders, resolvers and linear scales — isolating the cable, the device and the electronics before anything is replaced.
02 / Diagnosis
Likely causes
The handful of things that actually cause this — in the order we rule them out.
Damaged feedback cable
Flexing, chafing, coolant ingress or a strained connector breaks or intermittently opens the feedback signal. The commonest — and cheapest — feedback fault, often mistaken for an amplifier failure.
Failed encoder / resolver
A worn, contaminated or electrically failed encoder gives wrong or no position. We test the device independently of the drive to confirm.
Absolute-encoder battery
A flat backup battery loses absolute position; the axis alarms on power-up and needs re-referencing. We restore position data and fit a fresh battery.
Electrical noise
Poor shielding or earthing, or routing feedback alongside power cables, injects noise that corrupts the signal and causes intermittent faults that are maddening to chase without the right approach.
Linear scale contamination
On scale-feedback machines, oil, swarf or a damaged read-head gives erratic position. We clean, check and align the scale and read-head.
03 / Onsite
What our technician checks
A methodical path to root cause — not a scattergun of part swaps.
- 01Read the exact feedback/encoder alarm and its diagnostic
- 02Test the feedback cable end-to-end for continuity and intermittents
- 03Test the encoder/resolver/scale independently of the drive
- 04Check absolute-encoder battery and restore position data
- 05Verify shielding, earthing and cable routing for noise
04 / Fix it
Related services
The services that resolve this fault.
05 / Questions
Frequently asked questions
The drive alarms on a feedback fault — does that mean the encoder is dead?+
The fault is intermittent and impossible to catch. Can you still find it?+
Written & reviewed by MachineryFix Engineering Team — last reviewed — questions? Call +91 70751 47888
Encoder / Feedback Fault? Get a technician onsite.
Describe the fault and we'll match a verified specialist near you — onsite in hours across India, under 4 in Hyderabad. 24/7.