Kanban Inventory SOP

This procedure defines how Blitzpanel replenishes high-usage consumables and common parts using a two-bin/kanban system rather than work-order-driven procurement.

It exists to keep frequently used items in stock at the point of use without requiring the shop floor to generate individual purchase requests for every low-cost, high-volume part.

A disciplined kanban system prevents both stockouts that stall production and excess inventory tied up in slow-moving stock.

Applies to consumables and common parts stocked in shop-floor bins or the stockroom for general use across jobs: wire, ferrules, terminal blocks, DIN rail, wire duct, labels, fasteners, cable ties, and heat-shrink. TODO: confirm the full kanban-eligible part list.

Covers item selection, bin/card setup, the shop-floor replenishment trigger, the supplier reorder loop, receiving/restocking, and periodic recalibration of reorder points.

Does not cover project-specific buyout components ordered against a job BOM (see Procurement SOP) or components picked and staged for a specific job (see Kitting SOP).

Two-bin system — a replenishment method using two containers per item: one in use at the point of use, one in reserve; emptying the working bin triggers reorder of a full replacement.

Kanban card — a physical or barcoded card attached to a bin or location that signals "reorder this item" once it reaches the reorder point.

Reorder point (ROP) — the inventory level at which a new order is triggered, sized to cover expected usage during supplier lead time plus safety stock.

Reorder quantity — the fixed quantity ordered each time a kanban trigger fires, typically sized to a standard case, spool, or box quantity from the supplier.

Safety stock — buffer quantity held above expected lead-time usage to absorb demand spikes or supplier delays.

Lead time — elapsed time from placing a replenishment order to the item being available for use in the bin.

Point-of-use / supermarket location — the shop-floor location where kanban-stocked items are staged for direct pick by production staff.

Role	Responsibility
Shop-floor / Assembler	Pulls from the working bin; when a bin empties or the reorder point is reached, moves the card/empty bin to the designated collection point rather than quietly digging into reserve stock unflagged.
Materials / Stockroom Lead	Owns the kanban system: sets bin sizes, reorder points, and reorder quantities; maintains the kanban master list; runs the physical collection route.
Buyer / Purchasing	Aggregates triggered cards/bins on a set cadence, issues replenishment POs to approved vendors, and monitors supplier lead-time performance. TODO: confirm which role owns buying for kanban stock.
Quality	Confirms that any component added to the kanban list remains on the approved parts/vendor list and does not compromise the UL508A listing basis of panels it goes into.
Engineering	Approves additions, substitutions, or removals from the kanban part list for BOM equivalency before they take effect.

Two-bin racking/shelving and bin labels sized for the kanban part list. TODO: specify standard bin/rack hardware.

Kanban cards or barcode labels used to trigger replenishment. TODO: decide card format — physical card, bin-tag, or barcode scan.

Kanban master list recording each item's bin location, reorder point, reorder quantity, and approved supplier. TODO: name the system of record (spreadsheet, ERP module, etc.).

Approved Vendor List for eligible replenishment suppliers (see Approved Vendor List SOP).

6.1 Item selection & sizing

Select candidate items for kanban management: high-frequency, low-cost, low-obsolescence-risk consumables and common parts used across most jobs.

Confirm each candidate is on the approved parts/vendor list before adding it to kanban stock, since UL508A panel listing depends on components being drawn from evaluated/approved parts. TODO: verify exact UL508A clause on component evaluation and traceability.

Calculate the reorder point and reorder quantity for each item: ROP = (average daily usage × supplier lead time) + safety stock. TODO: populate usage rates, lead times, and safety-stock values per item.

6.2 Card & bin setup / labeling

Assign each kanban item a labeled two-bin (or two-location) setup at its point of use, with a card or barcode identifying part number, description, reorder point, and reorder quantity.

Stage the reserve bin behind or below the working bin so staff pull from the working position first (first-in, first-out).

Record the bin location, card ID, and reorder parameters on the kanban master list before the item goes live.

6.3 Replenishment trigger (shop floor)

When the working bin is emptied or reaches its reorder point, the operator pulls the card (or scans the trigger) and places it at the designated collection point immediately — do not wait until convenient.

Begin drawing from the reserve bin while replenishment is in process; if the reserve bin is also empty, escalate to the Stockroom Lead rather than substituting an unapproved part.

Do not return an empty bin to service without leaving its card at the collection point — the trigger must stay visible to the buyer until replenishment is confirmed.

6.4 Supplier replenishment loop (buyer)

Collect triggered cards/bins on a defined cadence. TODO: set collection/reorder cadence (e.g., daily, twice weekly).

Batch cards by supplier and issue a replenishment PO to the approved vendor for the item's standard reorder quantity, referencing the kanban card ID.

Confirm order acknowledgment and expected delivery date against the item's lead time; escalate items at risk of stockout before the reserve bin is exhausted.

Log each replenishment order — item, quantity, vendor, PO number, date triggered, date ordered — in the replenishment log.

6.5 Receiving & restocking

On receipt, verify part number, quantity, and condition against the PO and the item's approved-parts record before restocking. TODO: confirm this aligns with the receiving inspection steps in the Receiving SOP.

Restock the reserve position first; return the card to the bin/rack once the bin is filled and ready for use.

Update the kanban master list and replenishment log with the received quantity and date.

Flag any discrepancy — wrong part, damaged goods, short shipment — to the Stockroom Lead and Buyer rather than placing it into stock.

6.6 Periodic review & recalibration

Review reorder points, reorder quantities, and bin sizes on a defined cadence to reflect actual usage trends. TODO: set review cadence (e.g., quarterly).

Investigate any stockout or expedited order to determine whether the reorder point, quantity, or lead-time assumption needs adjustment.

Retire sustained low-usage items from kanban management and add newly high-frequency items as the part mix changes.

Kanban master list: item, bin location, reorder point, reorder quantity, approved supplier, and last-updated date.

Replenishment/trigger log: item, quantity, vendor, PO number, date triggered, date ordered, date received.

Cycle-count/accuracy records reconciling physical bin quantities against the kanban master list. TODO: set cycle-count frequency and method.

Stockout/expedite log capturing root cause and corrective action.

Retention period for kanban records. TODO: set retention policy.

Procurement SOP, Receiving SOP, Kitting SOP, Approved Vendor List SOP.

UL508A — Standard for Industrial Control Panels (component evaluation/listing basis for kanban-eligible parts). TODO: verify exact clause references before citing.

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