Multihead Weigher Troubleshooting: Causes & Fixes

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Problems on this page:

Giveaway creeping up Frequent misweighs and no-dump cycles Product sticking in trays and buckets Product broken or damaged in the weigher Discharge jams into the bagger Bucket gates not opening or closing Accuracy drops after washdown Slow product changeovers

Giveaway creeping up

Hits OEE: Performance

Symptoms: Average pack weight drifts well above target, combination misses force larger dumps, product cost per pack rises.

Too few heads available for combinations

Bring disabled heads back into service and fix chronic stickers; the algorithm needs several stable heads per dump to hit target tightly.

Uneven feed onto the top cone

Centre the infeed and set the dispersion vibrator so all pool hoppers fill evenly; starved heads force poor combinations.

Radial feeder amplitudes badly set

Tune per-head vibration so each weigh hopper receives close to target-divided-by-heads grams; oversized single-head loads wreck combination maths.

Sticky product clumping

Adjust product coating or temperature upstream and use dimpled or coated contact surfaces so portions release cleanly.

Prevention: Weekly head-availability review, giveaway trending per SKU, feeder amplitude checks at changeover, scheduled load-cell calibration.

Frequent misweighs and no-dump cycles

Hits OEE: Performance

Symptoms: Machine pauses waiting for a valid combination, reject rate climbs, downstream bagger starves.

Load cell drift or damage

Run the calibration check with test weights per head; replace cells that will not zero or repeat.

Product bridging in pool hoppers

Fit or tune hopper agitation, review product size vs hopper geometry and reduce moisture pickup at the infeed.

Static or product hang-up in weigh buckets

Clean and polish buckets, fit anti-static measures and check dump-door timing and seals.

Unstable infeed rate

Level-control the infeed conveyor to keep the top cone in its working band instead of flood-and-starve cycles.

Prevention: Daily test-weight checks, bucket and hopper cleaning at every changeover, infeed level control tuned per product.

Product sticking in trays and buckets

Hits OEE: Quality

Symptoms: Residue builds through the shift, portions hang then avalanche as double drops, washdown takes longer each night.

Wet or oily product on plain surfaces

Specify dimpled, embossed or fluoropolymer-coated contact parts for sticky recipes.

Scratched or worn contact surfaces

Replace polished parts once scratched; damage gives product a key to grip.

Condensation after washdown

Dry the machine fully and let it reach ambient before restart; cold surfaces sweat and glue fines to steel.

Vibration settings too gentle to self-clean

Add short clean-out bursts between dumps for high-residue products.

Prevention: Surface-finish inspection in PM, correct contact-part spec per recipe, full dry-down after washdown.

Product broken or damaged in the weigher

Hits OEE: Quality

Symptoms: Broken pieces, crumbs and fines in packs, complaints about appearance.

Drops too high between stages

Lower drop heights and use timing hoppers or soft chutes where the OEM offers them.

Bucket gates closing on product

Adjust gate timing and check for product trapped at the gates.

Feeder vibration too strong

Reduce radial feeder amplitude for fragile product.

Prevention: Fragile product settings stored as their own program.

Discharge jams into the bagger

Hits OEE: Availability

Symptoms: Product backs up in the discharge chute, missed dumps, bags with short weight.

Weigher and bagger handshake out of time

Re-time the discharge signal between weigher and bagger.

Product bridging in the chute

Check chute angle and surface for the product.

Bag too small for the dump

Check bag size against the product volume.

Prevention: Handshake timing recorded per product.

Bucket gates not opening or closing

Hits OEE: Availability

Symptoms: Heads drop out of combination, gate alarms, product spilling from a bucket.

Worn gate linkages or drive motors

Inspect and replace worn linkages or gate motors.

Product build-up on the gates

Clean the gates and buckets.

Damaged bucket

Replace damaged buckets.

Prevention: Gate checks after every cleaning.

Accuracy drops after washdown

Hits OEE: Quality

Symptoms: Misweighs and giveaway rise in the first hour after cleaning.

Water inside load cell modules

Check module seals and dry the modules before restart.

Buckets refitted in the wrong positions

Number buckets and their positions so each goes back where it came from.

Zero not taken after cleaning

Zero all heads after cleaning and before product.

Prevention: A restart routine after washdown: dry, refit by number, zero, test.

Slow product changeovers

Hits OEE: Availability

Symptoms: Changing product takes long and the first packs are off weight.

Settings not stored per product

Store a program for each product and select it at changeover.

Contact parts changed without a trolley or plan

Prepare parts on a trolley before the stop.

Cleaning access is slow

Agree a cleaning method and tools for the weigher.

Prevention: Changeover steps written and timed.

Guidance only. Always follow lockout/tagout and your site's safe-work procedures, and verify against OEM manuals before acting.

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Stop the same fault coming back

Recurring multihead weigher 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

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Methods that cut recurring stops: the six big losses · root cause analysis · preventive vs predictive maintenance · TPM · SMED & changeover