What causes fault code CONV-MERGE1 (Conveyor Merge — Collision Detected)?

Merge timing logic error — gap between products not maintained at merge point. Upstream conveyor speed mismatch — one feed line running faster than calculated. Merge photo-eye failed — PLC doesn't know a product is already in the merge zone. Product gap creator/spacer upstream not functioning — products too close together. Slug of products released from accumulation zone simultaneously instead of singulated

How do I fix fault code CONV-MERGE1?

Clear the jam at the merge point — remove damaged or misaligned products. Check all photo-eyes at the merge point — clean lenses and verify alignment. Verify both infeed conveyor speeds match the programmed values — check VFD speed parameters. Check gap-creation conveyor upstream of the merge — verify it creates minimum required gap. Review PLC merge logic timing — the hold-off timer may need adjustment for product size changes. If product size has changed, merge timing parameters may need to be updated in HMI

Conveyor Merge — Collision Detected

CONV-MERGE1

Merge conveyor detected a product collision at the merge point. Two products arrived at the merge zone simultaneously, causing a jam or product damage.

medium conveyor

conveyor merge collision timing gap jam

Probable Causes (ranked)

Merge timing logic error — gap between products not maintained at merge point
Upstream conveyor speed mismatch — one feed line running faster than calculated
Merge photo-eye failed — PLC doesn't know a product is already in the merge zone
Product gap creator/spacer upstream not functioning — products too close together
Slug of products released from accumulation zone simultaneously instead of singulated

Fix Steps

1 Clear the jam at the merge point — remove damaged or misaligned products
2 Check all photo-eyes at the merge point — clean lenses and verify alignment
3 Verify both infeed conveyor speeds match the programmed values — check VFD speed parameters
4 Check gap-creation conveyor upstream of the merge — verify it creates minimum required gap
5 Review PLC merge logic timing — the hold-off timer may need adjustment for product size changes
6 If product size has changed, merge timing parameters may need to be updated in HMI

Field Trick

When merge collisions happen intermittently, put the system in manual mode and test each infeed leg one at a time. If each leg works alone but collisions happen with both running, the gap timing is too tight. Increase the gap time by 200ms and test again.

Suggested Replacement Parts

Parts matched to fault category: Photoelectric Sensor

Banner QS18VP6D Photoelectric Sensor P/N: QS18VP6D Diffuse mode, 18mm barrel, 100mm range, PNP

AutomationDirect $65.00 Amazon $72.00 Grainger $85.00

IFM Efector O5D100 Photoelectric Sensor P/N: O5D100 Diffuse reflection, M18, 50-1000mm range, IO-Link

AutomationDirect $85.00 Amazon $95.00 Digikey $90.00

Prices are estimates. Verify part numbers match your equipment before ordering.

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