Conveyor Stops Under Load
A conveyor that stops once product is on it is describing a relationship between the load, the mechanics that carry it and the drive that reacts — three separate investigations behind one symptom.
What the symptom actually tells you
The most useful thing you can do before a visit is describe what was happening in normal operation when it stopped: what product was on the conveyor, how much of it, where on the line it was, and whether the machine had been running for a while. Load-related stops often follow a change nobody thought was significant — a heavier product, a longer accumulation, a new layout, a different speed.
Keep the observations apart. A conveyor that runs empty and stalls when loaded is one record; a drive that turns while the belt slips is another; a protection that trips and takes the whole machine down is a third; an intermittent jam at a transfer is a fourth. On some older driven-roller arrangements it is also worth noting whether the belt moves while the rollers it should drive do not.
None of these is a diagnosis. The same pattern can come from load, mechanical resistance, the transmission between drive and belt, or supply and control conditions, and manufacturer documentation separates those causes differently from one model family to the next. Diagnosis is a paid on-site visit with instruments and the documentation matching your model, followed by written findings and an estimate.
Which stopping pattern matches yours
These are categories to narrow the question before a visit, not a remote diagnosis. Confirmation requires on-site measurement.
- Runs empty, stalls once loadedPoints toward the relationship between demand and capability. Record the product, the quantity, the section involved and any recent change.
- Drive turns but the belt slipsFocuses attention on transmission, pulley and belt-path condition under the observed load, without ruling out other drive or control issues. Note whether it slipped from the start or only later.
- Whole machine stops — motor protection or supply tripsRecorded as an electrical event. Note what tripped, if visible from a normal operating position, and whether it repeats at the same point.
- Intermittent jam at a transfer or transitionGeometry, product handover and sensing all sit here. Note which transfer, which product and how often.
- Belt moves but driven rollers do notUseful mainly on older driven-roller conveyors, where documentation treats this as a distinct observation from a slipping belt.
What you can safely observe yourself
Observations from your normal operating position, with no guards removed and nothing adjusted. If the machine has a display, capture what it shows only if that can be done safely from where an operator normally stands.
- Record the conveyor model and serial number, and the drive or controller model if labelled
- Describe the product on the conveyor when it stopped: size, weight and quantity
- Note which section or zone was involved and what the rest of the line was doing
- Note whether it had been running a while, or stopped soon after starting
- Photograph any message or indication shown, from a safe normal position
- Note recent changes: product, speed, layout, service or parts fitted
- Do not repeat loaded runs or restart it to see when it stops again
- Do not adjust belt tracking or tension, especially with the belt moving
- Do not remove guards, reach into the belt path, or work near a transfer
- Do not defeat, bridge or reset protections repeatedly, and do not set anything to restart automatically
What requires a technician on site
- Load and product demand compared with what the specific model is documented to carry
- Mechanical resistance through the belt path, rollers, pulleys and bearings assessed on site
- Transmission between drive and belt inspected for condition and slip
- Supply and control conditions measured after safe isolation where appropriate to the work
- Motor and drive behaviour under load measured rather than inferred from a stop
- Indications recorded exactly and read against documentation for that model and revision
- Tension, tracking and lubrication guidance is model-specific; some belts and rollers are designed with no such service task at all
- Sealed drive rollers are not opened; they are assessed and, if needed, replaced as a unit
- Guards and interlocks are tested, never bypassed
- Regulated electrical work is performed only within KONGRA's legal license scope, or coordinated with properly licensed independent contractors
- KONGRA is independent and is not affiliated with, endorsed by or authorized by any manufacturer named here
What to send with your request
The more of this arrives up front, the more useful the first visit is.
- Conveyor model and serial number, and drive or controller model
- Product, weight and quantity on the conveyor when it stopped
- The affected section or zone, and whether the stop repeats at the same point
- Any indication shown, photographed from a safe position
- Recent changes to product, speed, layout or service
These details are optional and help us prepare for your visit.
Manufacturer references
- Dorner 2200 Series installation, maintenance and parts manual 851-816 Rev F (PDF)Dorner 2200 Series, 100 pages; PDF page 29 consulted, where overload, dirty or worn pulley condition and intermittent jamming are described separately. The same document states no lubrication is required and that V-guided belts do not require tracking adjustment. Applies to the 2200 Series only.
- Hytrol 190-LR / 190-ACZ conveyor bulletin 558 (PDF)Hytrol 190-LR and 190-ACZ, bulletin 558, June 2005; PDF page 30 consulted, where a motor overload, a slipping belt and a belt that moves without driving its rollers are treated as separate observations. Legacy equipment, not the E24 platform; no adjustment tables or procedures are reproduced here.
- Interroll RollerDrive EC5000 user manual, version 3.3 (UL, US/Canada) (PDF)Interroll RollerDrive EC5000, version 3.3, October 2021; page 16 consulted, where an overloaded roller's temperature and load protection can stop a zone. AI and BI variants and 24 V and 48 V versions differ, and some restart behaviour is automatic, so no owner restart instructions are given here.
Related conveyor and drive pages
Frequently asked questions
It runs fine empty, so the machine must be healthy — is that right?+
Not on its own. Running empty only shows the conveyor can move itself. Load adds mechanical resistance, current draw and heat, and a machine can be perfectly capable of running empty while something in the drive, the belt path or the load itself is beyond what it will carry. Both observations are useful; neither is a conclusion.
Should we keep loading it to see when it stops?+
Please do not. Repeating loaded runs after a stop adds heat and stress, and it can change the very conditions a technician needs to observe. Stop, note what was happening in normal operation, and book the assessment.
The drive shows a fault, so is the drive broken?+
A fault indication tells you the drive reacted to a condition. That condition can be in the load, the mechanics, the motor, the supply or the drive itself. The indication is recorded exactly as shown and then read against the documentation for that model, rather than treated as a named failed part.
Can I adjust belt tracking or tension while it runs to see if that helps?+
No. Adjustments near a moving belt, and any work with guards removed, are not owner tasks. Some conveyor belts are also designed so that tracking adjustment is not part of normal service at all, depending on the model.