Most OEM charger projects do not fail because a stage takes too long. They fail because two stages run in the wrong order: artwork is approved before the enclosure is frozen, or certification is booked before a worst-case build exists. The sequence below is the dependency chain that keeps a launch date defensible.
The dependency chain that sets your launch date
Four decisions drive everything downstream: the platform, the enclosure, the port and plug configuration, and the market set. Each one has a technical consequence. The platform determines what can be certified cheaply; the enclosure determines tooling; the port configuration determines the thermal worst case; the market set determines the plug kit and the compliance documents. Until those are fixed, every date you receive is an estimate built on assumptions.
Stage 1: specification freeze and platform choice
The freeze does not need to be a full engineering package, but it must state the wattage, the port layout, the plug strategy, the target markets, the enclosure intent and the branding requirement. Where an existing platform can carry the specification, this stage is short and mostly commercial. Where a new form is required, the freeze is the input to the mechanical design.
Stage 2: tooling and engineering samples
Tooling starts once the mechanical design is frozen, and it runs through steel cutting, machining, assembly and trial. The trial loop – T1, T2 and further rounds – corrects dimensions and appearance before the mould is accepted. Engineering samples built from these trials are what the design review and, later, the test house will see.
Stage 3: certification in parallel with packaging artwork
Certification should start as soon as a representative worst-case build exists, and it should run in parallel with artwork development rather than after it. The two workstreams touch at one point: the label and the user manual must state the model identification, ratings and warnings that the technical file describes. Freezing the artwork before certification closes risks a reprint when the marking text changes.
Stage 4: golden sample and packaging proof
The golden sample is the physical reference that production will be measured against: the approved enclosure, colour, print, cable, accessories and packaging as they will ship. A packaging proof confirms the board, insert, print colour and language version. Both should be signed and retained, because they are what decides a dispute later about whether a shipment matches the approved product.
Stage 5: pilot run and mass production
A pilot run validates the process rather than the design: it proves that the assembly line, test fixtures, packout and inspection gates produce conforming units at rate. Pilot output is also the first realistic yield data. Only after the pilot should a full production schedule be committed, because the pilot is what turns an engineering success into a manufacturing plan.
| Stage | Entry condition | Exit deliverable |
|---|---|---|
| Specification freeze | Platform and market decision | Frozen specification and costed quotation |
| Tooling and samples | Mechanical design frozen | Accepted mould and engineering samples |
| Certification | Worst-case build available | Reports, marking and technical file |
| Golden sample | Artwork and packaging finalised | Signed reference unit and packaging proof |
| Pilot and production | Golden sample approved | Process validation and production release |
Where projects slip and how to compress honestly
Schedules slip at four predictable points: late artwork, a certification failure that requires a design change, a mould correction that runs beyond the planned loop count, and a component substitution that invalidates a test. Compressing honestly means shortening the loops, not skipping them: use a platform with existing certification, run artwork and testing in parallel, freeze labels early, and approve components before the pilot rather than during it.
RACI: who owns each decision
Assign one owner per decision. The brand owns the market set, the launch date and the artwork approval; the factory owns the platform recommendation, the worst-case build, the test submission and the process validation. Where ownership is shared without a tie-breaker, the project waits. A single project owner on the factory side, from quotation through reorders, removes most of that friction.
Project plan template for a charger programme
- Platform and specification freeze date
- Mechanical design release and mould order date
- Trial loop dates with acceptance criteria
- Worst-case build date and test submission date
- Artwork freeze and packaging proof date
- Golden sample approval date
- Pilot run date and production release date
Frequently asked questions
Can certification start before tooling is finished?
It can start once a representative worst-case build exists, which may be an engineering sample rather than a production moulding. If the enclosure changes afterwards, the test house will normally require a review or a retest of the affected parameters.
How long does an OEM charger project take end to end?
It depends almost entirely on whether the enclosure is new. A platform-based re-badge avoids tooling and certification discovery; a new form adds the mould loop and the associated test submissions, and those two stages dominate the calendar.
What must be frozen before tooling begins?
The mechanical design: enclosure geometry, wall thickness, parting lines, mounting features and the internal layout that determines clearances. Changing those after steel is cut is the most expensive kind of change in the project.
Next step
Wecent Group runs engineering, pilot builds and volume production on the same site in Bao’an, Shenzhen, with one project owner from quotation to reorder. Send your specification and target markets to the contact page. Related reading: sample approval gates, certification project plan, mould trial reports and OEM/ODM manufacturing. External references: USB-IF documentation, IEC standards, EU CE marking, FCC equipment authorisation, EU RoHS directive and ISO 9001.