10 Ways to Improve RFQ for Electronic Manufacturing Services
Spending a lot of time writing the request for quote (RFQ) for electrical manufacturing services is often a low priority for original equipment manufacturers (OEM). But RFQ errors can cause significant electrical assembly problems and program delays – problems and delays that can actually counteract much of the high priority effort spent by engineers on the actual design. To avoid many of these problems and delays in your next printed circuit board assembly, consider the following 10 ways to improve your next RFQ.
1. Include All BOM Levels, with AVL’s
The RFQ should include the full exploded bill of material (BOM) for every level the electronics manufacturing service (EMS) needs to build, test, or otherwise handle. These BOMs should be the most up to date version available and include the approved vendor list (AVL) for each component part.
2. Clearly, indicate parts that will be consigned
Consigned parts are those provided by the OEM to the EMS for the build, rather than those the EMS will procure themselves. Parts are consigned because they are custom, have special pricing, or for a handful of other reasons. Indicating clearly, up front in the RFQ, which parts are consigned is very important.
3. Clarify any special or unusual build requests
During prototype or new product introduction (NPI) builds, OEMs often need to make special deviations from the documented design. These special instructions include additions, subtractions (DNI), substitutions, and so on. They can also include unique variants or processes to evaluate.
4. Document programmables
Every component that needs to be programmed should be documented in the RFQ. This includes parts that need to be pre-programmed before the build, parts that need to be programmed after the printed circuit assembly (PCA) build as part of the test, and parts that need to programmed during or after box build via external interfaces with the product.
5. Specify test expectations at each build stage
Depending on the type of design and the intent of the build, test expectations may vary. The RFQ should specify all testing expected of the EMS, from AOI, x-ray, flying probe, or ICT performed at the PCA level, to functional test or environmental stress screening performed at the system/box build level.
6. Include all mechanical assembly instructions
Even simple rapid prototype PCA builds usually require some level of mechanical assembly. Providing instructions for that assembly in the RFQ helps the EMS accurately quote the effort. PCA mechanical assembly items that are sometimes overlooked include standoffs, heatsinks, and ICs or modules that mount in sockets.
7. Specify labeling, serial number, and barcode expectations
Quality EMS manufacturers will have a good serial number, barcode, and labeling systems. If OEMs have their own expectations, such as specific serial number formats or specific label placement locations, it is important for those to be specified in the RFQ.
8. Define turn times, including relevant program milestones and decision points
OEMs can pay a higher price for faster turnaround times, or save money by permitting a slower turnaround. It is important for OEMs to define what they want to be quoted in the RFQ. Other relevant program milestones or decision points can also be very helpful to the RFQ process.
9. Share expected yield rates and rework plan
Target build yields can help to focus the EMS quoting process. And advance planning of the expected rework, and the return material authorization (RMA) process, also helps. Quotes will be more complete and more accurate if these post-build expectations are shared in the RFQ.
10. Include engineering contacts for technical questions
OEMs often only include engineering project managers or coordinators as contacts on RFQs. This is a mistake if getting the most accurate quote, quickly, is desired. OEMs should include lead engineers on RFQs to ensure the fastest possible responses to technical questions or concerns.