Roller Conveyor Motor Won’t Start or Slows Down? 4 Causes and Fixes
Quick answer: The most common roller conveyor fault is a motor that will not start, or slows down right after starting. There are usually four causes: a wiring fault, a voltage drop, a contactor fault, or too many starts in a short time. Check in the order wiring → voltage → contactor → start frequency and most problems are solved quickly; routine maintenance greatly extends the life of the motor and the whole line.
The motor is the heart of the machine: fix faults promptly and maintain it regularly to keep the roller conveyor running reliably.
Troubleshooting table
| # | Possible cause | How to check | Fix |
|---|---|---|---|
| 1 | Wiring fault | Check power cable and terminals for looseness, breaks or a lost phase | Repair the wiring immediately; tighten or replace |
| 2 | Voltage drop | Measure voltage at the motor with a multimeter | Restore normal voltage; check supply and cable size |
| 3 | Contactor fault | Check contactor pull-in, burnt contacts, overload relay trips | Replace faulty or overloaded components |
| 4 | Too many starts in a short time | Review start/stop frequency; check for thermal trip | Reduce operations and let the motor cool before restarting |
Step by step
- Isolate and check the wiring: make sure cables and terminals are tight and unbroken; on three-phase motors look especially for a lost phase;
- Measure the voltage: well below rated voltage, the motor lacks torque and struggles to start or slows after starting;
- Check contactors and protection: burnt contacts, poor pull-in or a tripped thermal relay all stop the motor running normally — replace the faulty part;
- Control start frequency: repeated starts in a short time overheat the motor and trip protection; reducing operations restores normal starting.
If all of these are fine, check for overload or mechanical binding — a seized roller bearing, a jammed chain or built-up product.
Routine motor maintenance
- Clean dust off the motor body and cooling fins regularly;
- Check terminal tightness periodically;
- Check gearbox oil level and chain lubrication on schedule;
- Watch for unusual noise, vibration and temperature rise.
FAQ
The motor runs but the rollers don't turn — why?
Usually a drive-train problem: a broken or slipping chain or belt, a loose sprocket key, or an overloaded, jammed line. Stop and inspect the transmission.
The motor keeps overheating and tripping — what should I do?
Check whether the load exceeds the design, starts are too frequent or cooling is blocked. If the line has been lengthened or loads increased, a larger motor or zoned drives may be needed.
Related equipment
- Motorized Roller Conveyor — drive built into the roller, few exposed parts
- Belt-Driven Roller Conveyor — quiet, no lubrication
- Need on-site repair? Contact our engineers.
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