In this guide 6 sections
A panel cannot ship with a hole. One missing breaker, relay or enclosure stops wiring, testing and dispatch together, because every finished section, test sheet and delivery slot depends on that single part, however small. A shortage list shows the gap early.
A panel is only as complete as its slowest part
A job may carry hundreds of listed items, and most arrive on time, yet one moulded case breaker with a long lead time can stall the assembly.
The wait is the smaller cost. Half wired sections crowd the floor, the test bay stays blocked by an unfinished panel, and the customer’s site engineer keeps phoning to ask when the truck will leave.
Wiring crews cannot close a section with a blank slot on the mounting plate, so the testers have nothing to run and dispatch has nothing to load. One gap blocks three teams.
- Moulded case and air circuit breakers
- Protection relays and meters
- Special enclosures and painted doors
- Contactors with a particular coil voltage
- Cable glands and lugs for odd cable sizes
Why the shortage stays hidden until build day
Stock is counted by item, not by job. The store sees ten contactors on the shelf and calls it fine, yet three jobs each need four of them, so the third job will be short by two.
The purchase order is raised, yet nobody compares the promised delivery with the build start, because a supplier’s confirmation lands in one buyer’s inbox and nobody else sees it.
Substitutes cause trouble too. A relay marked equivalent may have a different footprint or auxiliary contact count, and the drawing no longer fits the door cutout or the terminal rail. Ask who last looked at the order date. Often the answer is nobody. A purchase order that is raised and forgotten looks identical to one on schedule, right up to the morning the wiring crew finds the gap.
Build a shortage list by job
Take each job’s bill of materials and compare it with free stock, not reserved stock, then add what is on order with the supplier’s confirmed date. Each row shows a shortfall and its arrival.
Sort the list by build start. A breaker shortage three weeks ahead is a purchasing task, while the same shortage on build morning is a crisis that idles the wiring crew and the test bay.
Reserve stock against the job the moment it is confirmed, so free stock falls honestly and a second panel job asking for the same breakers sees the true number. Reservations are the whole trick.
- Item code and description
- Quantity needed against quantity free
- Order number and confirmed date
- Job build start and dispatch date
- Approved substitute, if any
Decide early what can be built around
Some gaps can be worked round. Wire the busbar sections and control wiring first and fit the late breaker at the end, but plan it when the shortage is known, not on the shop floor.
Other parts, like an enclosure, block everything. For those, push the supplier, ask for part shipment, or approach an alternate source with the customer’s consent in writing, because substitute enclosures change door cutouts and paint shade.
Warn the customer early. A phone call about a relay three weeks ahead is received far better than an apology at dispatch, and it lets the customer rearrange site crews and crane hire.
Review the list on a fixed day every week
Hold a short weekly meeting. Go job by job from the earliest build date with purchase, planning and the store, and give every shortage a named buyer and a day to phone the supplier.
Track each supplier’s real delivery record. Parts that arrive late again and again deserve a safety stock of their own, whether contactors with an unusual coil voltage or glands for odd cable sizes. Begin today by pulling the bill of materials for your next three jobs, comparing each line with free stock and marking everything that is short.
Job shortage list
One row per short item. Columns cover job number, item code, description, quantity needed, quantity free, purchase order number, supplier confirmed date, build start date, days of slack, owner and action. A header block names the job, customer and dispatch date, and a footer lists the buyer who signs off each action.
Open a blank worksheet to printQuestions owners ask
What is a bought out item?
It is a part you buy ready made and fit into the panel, such as a breaker, relay, meter or enclosure, instead of making it in your own shop.
Should we stock every long lead item?
No. Stock only the long lead items that repeat across many jobs and have a history of late delivery, since idle stock of one off meters ties up shelf space. Order one off parts at confirmation.
How early should purchase orders go out?
As soon as the drawings are approved, because waiting for a final bill of materials often costs more weeks than a small change later costs in rework. Long lead items go first.
Can software build this list?
Yes, if bills of materials, stock and purchase orders sit in one system linked by job number, so the list refreshes itself each morning. A spreadsheet can do it for a few jobs.