Problems on this page:
Wire breaking during winding
Hits OEE: Availability
Symptoms: The wire snaps during winding and the coil is scrapped or has to be restarted.
Tension set too high for the wire size
Set the tensioner for the wire diameter and check it with a tension gauge.
Burr or groove on a wire guide or nozzle
Inspect the wire path and replace worn guides and nozzles.
Acceleration too fast at the start
Ramp the spindle speed up gently at the start of each coil.
Wire spool feeding unevenly
Check the spool payoff and its brake so the wire leaves the spool smoothly.
Prevention: Wire breaks recorded per product and spindle.
Uneven layers or crossovers
Hits OEE: Quality
Symptoms: Turns pile up, cross over or leave gaps in a layer, and the coil comes out oversize.
Traverse pitch wrong for the wire
Set the traverse pitch to the actual wire diameter, including its insulation.
Traverse reversal points wrong
Set the reversal points to the inside of the bobbin flanges.
Wire tension varying during the coil
Check the tensioner holds a steady tension at all speeds.
Bobbin dimensions varying
Check incoming bobbins against their drawing.
Prevention: Layer quality checked on the first coils of each run.
Turn count wrong
Hits OEE: Quality
Symptoms: Coils fail resistance or inductance checks because the number of turns is off.
Counter or encoder fault
Check the turn counter against a slow manual count.
Wire slipping on the bobbin at the start
Secure the wire start so the first turns are not lost.
Program changed or the wrong program loaded
Check the program number against the work order.
Machine stopped and restarted in the middle of a coil
Test or scrap coils that were interrupted, since the count may be lost.
Prevention: Electrical test on every coil, with failures recorded by cause.
Wire insulation damaged
Hits OEE: Quality
Symptoms: Coils fail insulation or shorted turn tests.
Sharp edges on guides or bobbin flanges
Find and remove sharp edges along the wire path and on the bobbins.
Tension too high, so the wire is stretched
Reduce the tension to the value set for the wire size.
Wire already damaged on the spool
Check incoming wire spools and how they are stored and handled.
Coils damaged in handling after winding
Check trays, tape and handling between winding and test.
Prevention: Insulation test on every coil.
Wire tension varying
Hits OEE: Quality
Symptoms: Coil dimensions or resistance vary from coil to coil.
Tensioner felt or spring worn
Service the tensioner and replace worn felts and springs.
Spool brake uneven
Check the spool brake and payoff.
Winding speed changing during the coil
Keep the speed profile the same for every coil.
Dirty pulleys in the wire path
Clean the pulleys and check they turn freely.
Prevention: Tension checked with a gauge at start-up.
Terminations failing
Hits OEE: Quality
Symptoms: Wire ends wrapped on the pins come loose or break, or solder joints fail.
Too few wrap turns on the pin
Set the number of wrap turns in the program for the pin size.
Wire nicked when the insulation is stripped
Check the stripping method and settings.
Pin position varying between bobbins
Check the bobbins against their drawing.
Solder bath temperature or dip time wrong
Check the solder bath against the process settings.
Prevention: Termination pull test on sample coils.
Spindle vibration
Hits OEE: Availability
Symptoms: A spindle vibrates at speed and the winding becomes uneven.
Bobbin holder out of balance
Check and balance the bobbin holder or tooling.
Spindle bearings worn
Replace the bearings.
Collet worn
Replace the collet so the bobbin runs true.
Machine not level or not secured
Level and secure the machine.
Prevention: Spindle run-out checked on the maintenance plan.
Wire not catching at the start
Hits OEE: Availability
Symptoms: The wire fails to anchor at the start of a coil and the cycle stops.
Gripper or clamp worn
Replace the worn gripper jaws.
Start position not taught correctly
Teach the start position again for the bobbin.
Wire end bent by the cutter
Check the cutter blade and its position.
Air pressure low to the gripper
Check the air supply.
Prevention: Start failures recorded per shift.
Slow product changeovers
Hits OEE: Performance
Symptoms: Changing to another coil type takes long, and the first coils need many adjustments.
Tooling not prepared before the change
Prepare bobbin holders and guides while the previous run finishes.
Programs not stored per product
Store a proven program for every coil type.
Wire change slow
Stage the next wire spool beside the machine.
Proven settings not recorded
Record the settings that gave good coils and load them at the next change.
Prevention: Changeover time recorded per product.
Guidance only. Always follow lockout/tagout and your site's safe-work procedures, and verify against OEM manuals before acting.
Related equipment guides: electric motor · transformer · ultrasonic welder · wave solder machine · selective soldering machine · crimping machine · cable extrusion line
Stop the same fault coming back
Recurring coil winding machine stops usually trace to a cause you cannot see by hand. The partner we recommend is Fabrico: it tracks OEE and downtime live from PLCs, IoT sensors or AI cameras; where cameras are fitted, the video of a stop sits next to its machine data so the cause can be reviewed; and a technician opens the work order from the stop in the same system. Data is hosted in the AWS EU region, and Fabrico and the company behind it hold ISO/IEC 27001, ISO/IEC 20000-1 and ISO 9001.
Book a Fabrico demo
The directory stays free.
Related tools: full troubleshooting directory · OEE calculator · downtime cost · MTBF / MTTR · glossary
Methods that cut recurring stops: the six big losses · root cause analysis · preventive vs predictive maintenance · TPM · SMED & changeover