Pick To Light
Pick-to-light is a light-directed picking system used in warehousing, distribution, kitting, and manufacturing. It guides operators to the correct storage location and quantity using illuminated displays, LEDs, and confirm buttons tied to a WMS/ERP or production control system. Each confirmed pick updates inventory and workflow in real time, supporting paperless, hands-free material issue.
In real manufacturing, pick-to-light is a poka-yoke method for kitting, assembly support, and raw material staging. When a work order is released, the WMS or ERP activates lights at the exact bins on the bill of materials. An operator walks the pick path, pulls the displayed quantity into a kit tote, and presses confirm; the system decrements stock and advances the work instruction in real time. This eliminates paper pick lists and handheld scanning from high-volume line-side replenishment, allowing workers to keep hands on the tote and eyes on the light. It excels in split-case and broken-case environments with many small, repetitive picks, preventing mix-ups of look-alike parts. The key dependency is operational discipline: physical bins must match system locations, and forward pick faces must be kept full with timely replenishment. When those conditions hold, pick-to-light reduces part mix-ups, improves traceability, and keeps assembly lines moving.
- Wrong-bin inventory: if physical bin labels, rack locations, or item master data do not match the system location, lights point to the correct system position but the wrong SKU, creating shortages, mis-kits, and downstream line stoppages.
- Replenishment lag: when forward-pick locations run empty because replenishment is delayed, operators reach an illuminated bin and find nothing, stalling labor, forcing exception handling, and breaking sequence-critical kitting or assembly flow.
- Weak zone handoffs: in zone-pick or sort-to-order setups, lights guide local picks correctly but incomplete orders result when transfer rules, consolidation logic, or cross-zone handoffs are poorly designed, causing bottlenecks at the next station and delayed shipping or assembly release.
Is pick-to-light the same as put-to-light?
No; pick-to-light guides removal from inventory locations, while put-to-light guides placement into order bins or sortation locations.
What systems does pick-to-light typically integrate with?
It commonly integrates with a WMS or ERP that sends pick tasks and receives confirmation updates.
Why is pick-to-light used instead of paper pick lists?
It reduces manual searching, shortens decision time, and lowers picking errors by showing the exact location and quantity at the point of work.