Compare the same handoff before comparing prices
| Decision | PCB assembly scope | Box build scope |
|---|---|---|
| Released inputs | BOM, fabrication/placement data, assembly notes and board acceptance | Board package plus mechanical, harness, software, label and packing definition |
| Material ownership | Bare PCB and electronic BOM items as agreed | Also enclosure, harnesses, accessories and packing materials where included |
| Inspection boundary | Solder joints, placement and agreed board features | Also mounting, fasteners, fit, routing and connector engagement |
| Functional boundary | Functions accessible at the defined board-test interface | Functions exercised through the assembled product interfaces and configuration |
| Release records | Agreed build, inspection and board-test records | Also assembly/configuration identity, system-test and pack-out records |
| Delivered state | PCBA or agreed board-level subassembly | Defined integrated subassembly, configured unit or packed product |
These are scope distinctions to agree, not a claim that every project includes every operation. The PCB Assembly service and Box Build service define the respective work packages.
What changes once the board enters the enclosure
The enclosure can change connector access, cooling, cable bending, antenna placement and the test interface. Confirm the relevant operating conditions and installation arrangement before releasing the assembly sequence and final-test plan. Board-level checks can remain useful while additional integration checks address new risks.
For a product with a cable set, distinguish a failed board from a wrong pinout, incomplete connector seating, routing damage or incorrect configuration. The harness and PCBA integration guide maps those risks to checks and records.
Use a clear responsibility split
Identify who supplies each item, owns design changes, approves substitutions, provides firmware and defines the product acceptance criteria. State who prepares fixtures and programming assets, and how one-time work is quoted. Combined work packages can be governed through the electronics contract manufacturing program.
Illustrative quotation comparison
Two suppliers may quote the same controller board while one includes only board assembly and the other includes a harness, enclosure, released firmware, installed-unit checks and packing. The quotations are comparable only after both scopes identify the same handoff state and included tasks. This is an illustrative comparison; no price or customer outcome is asserted.
Record exclusions and unresolved decisions beside each quotation. Include qualification, calibration or product certification only when the method, responsible party and evidence are separately agreed.
Prepare the product release
Use the whole-product RFQ checklist to add the missing integration inputs. Specify the inspection and functional-test coverage and retain a reviewed action list for the pilot release. Discuss the required manufacturing handoff with the product stage, available files and open questions.