Managing, versioning, tracking: assemblies/PCBs/BOMs/Assembly Variants/etc. - Page 1
Forum section: electronics / projects

author: incf
author_rank: Frequent Contributor
timestamp: February 08, 2025, 12:28:35 pm
content: In a commercial context, it is common to build products that are assemblies of many different 'things'.Suppose you had a product that consisted of:A 'big box'/ChassisBatteriesholddown/mounting hardwareWire hardnesses, connectors, etc.Variations in how the chassis is assembledModule Aa small boxfuses, screws, connectors, wire harness, etc.variations in how the module is assembleda PCBmany components like a "1 kilohom 1% resistor" that has many suppliersvariations in how the PCB is assembledModule Ba small boxfuses, screws, connectors, wire harness, etc.variations in how the module is assembleda PCBmany components like a "1 kilohom 1% resistor" that has many suppliersvariations in how the PCB is assembledThere is a hierarchy of BOMsThere are a bunch of designs (plastics, PCBs, harnesses, etc.) done in different CAD programsThere are different suppliers, processes, etc. that change over timeThey all have minor variations in how they are assembledDifferent parts of the system get revised at different times/ratesGeneric and hardware components might change frequentlyetc.It's not the most exciting subject, but, how does one keep track of it all?From soda fountains to aircraft, and everything between, it is a all very different in the specifics, yet very much the same in the generics types of problems that arise.Many companies have ERP (enterprise resource planning) software - but in my experience there often were all sorts of limitations that caused 'engineering stuff' to be separate from 'business/sales/accounting/etc. stuff' (other than mundane social boundies and lack of real incentive to keep things in sync, for example, the software might not represent nested hierarchies, or generic components, etc. - so that mapping "1:1" from engineering design into ERP is not just 'too much work' but actually impossible). Often components/assemblies/etc. are represented different ways in different situations - and often in a way that does not bear much resemblance to reality (the accountant might want things represented one way, the engineer another way, the factory in a similar but different way, and the sales person in a completely different way from the other three).Perhaps one ends up with spreadsheets in numbered/nested folders, or maybe these days, piles of git repositories/branches/folders/commits. Often from the outside it looks like a poorly kept/disorganized mess. From the inside, it often looks much the same.There are a millions ways to keep track of this stuff, and every company is very different. I find myself wanting to hear how others deal with complex products/assemblies that live for long periods of time.

author: electron_plumber
author_rank: Regular Contributor
timestamp: February 10, 2025, 02:33:15 pm
content: The last three companies I've worked for used Teamcenter for product lifecycle management (PLM).

author: krish2487
author_rank: Frequent Contributor
timestamp: February 10, 2025, 04:09:32 pm
content: Quote from: incf on February 08, 2025, 12:28:35 pmYou got it wrong here.. In any PLM / ERP software you have (many) databases with different data... linked to other databases and then you have views...It doesnt matter what "view" one wants.. an ERP / PLM software most normally will have the means to make that happen..What this means in real life is that the same product can be shown differently for a CAD person, FW person, Hardware person, accounting, NPI, Manufacturing, Service, Sales and so on..Its just ( to oversimplify it...) a query that is returning data and presenting it in the way you want it to..My experience is limited but having worked with a few ERP solutions... they all had this ability..What took blood, sweat and tears was getting to understand what the damn end user wanted in the first place...This not only meant understanding their existing processesses but having to come up with one if they didnt have one in place... this usually meant coordinating with multiple people / teams... getting them to agree and sign off on it..Implementing it is another pain point for some ERP solutions..Edit : variants are bog standard feature for any ERP solution worth its salt... I dont recall having seen one without support for an assembly variant.. all the way from a PCBA to the finished goods.

author: ftg
author_rank: Frequent Contributor
timestamp: February 10, 2025, 05:35:09 pm
content: Yep. Any ERP system worth it's salt does exactly that.At least the one's I have used.For the design engineer some tools like Altium Designer also support assembly variants for products where there is a common PCB used for multiple models.

author: abeyer
author_rank: Frequent Contributor
timestamp: February 10, 2025, 09:14:31 pm
content: Quote from: krish2487 on February 10, 2025, 04:09:32 pmYeah, I think those points kind of add up to the issue pointed out. The difficulty of designing and implementing this, even with an ERP that "supports" it, may mean it never happens or is implemented poorly or incompletely... leading to engineering going off to find their own solution to their own needs, rather than wait on a centralized ERP team to fix the deficiencies there.

author: artag
author_rank: Super Contributor
timestamp: February 10, 2025, 09:25:14 pm
content: I just went to a trade show here in the UK. Seemed like half the stalls were advertising some sort of MRP software. Must be the in-thing in the business at the moment, probably because it potentially reduces waste and mis-stocking. I wasn't looking for that sort of thing but if I had been, trying to compare&contrast all the options would have been a major task.In those circumstances I'd have picked the cheapest, wait 5 years, then pick the one that appears to fix all the problems it caused.Whether it does that at reasonable cost is a moot point. I've been at a couple of places during SAP takeover. It seemed to consume every resource for months and change every process to meet their system, or involve complicated changes to SAP to accomodate existing systems. I don't know whether it eventually made things more efficient, both companies collapsed before any gain was visible. Whether SAP caused that or it was a last-ditch attempt to fix management that failed, i don't know. But it sure costs a lot more than the sticker price to install.

author: kaevee
author_rank: Regular Contributor
timestamp: February 11, 2025, 01:57:09 am
content: Check out Moqui Framework.Moqui is a powerful open-source ERP framework that’s perfect for electronics manufacturing. It provides:Integrated MRP & Inventory– Real-time material tracking and traceabilityProduction Planning & Scheduling– Optimize SMT, AOI/AXI, reflow, and assembly workflowsScalability & Flexibility– Customizable to meet EMS-specific needsCost-Effective– No licensing fees, full control over data and processesI am starting work on integrating Moqui with our EMS facility.