What is considered a pot "board lock" - Page 1
Forum section: electronics / general

author: typoknig
author_rank: Regular Contributor
timestamp: December 04, 2019, 07:04:46 am
content: I have always thought board locks were an additional support structure on a pot, not the signal pins themselves. The image below shows what I'm talking about. Note the kink in the board locks:Thispot and others like it sold by Digikey and others are described as having board locks as well. If you look at the center pin for both gangs you will note the same style of kink the traditional board locks shown in the image above have.Is the kink in a signal pin enough to be considered a board lock?

author: KL27x
author_rank: Super Contributor
timestamp: December 04, 2019, 07:11:27 am
content: Dunno if you care about the semantics or the way to source the pot you want.I'd guess the former is "yes," because you have already discovered this to be the case?If the latter, you might want to add "shielded" to your search criteria.

author: tom66
author_rank: Super Contributor
timestamp: December 04, 2019, 07:13:20 am
content: I think that's optimistic to call the bent pins "locks" - but then again I doubt you will pull that off a board even with just those. The big issue will be the fracturing of the solder joints.Digi-Key is just a catalog, they list what manufacturers say, so if a manufacturer says it has 'X', Digi-Key will say the same.

author: typoknig
author_rank: Regular Contributor
timestamp: December 04, 2019, 07:23:19 am
content: Quote from: KL27x on December 04, 2019, 07:11:27 amI'm working with Bourns to get some pots made to my specs. I was just surprised/confused by the first drawing they sent me because their terminology/semantics didn't seem to align with Digikey descriptions or their owndatasheetfor the PTD90 series of pots which makes no mention of board locks.

author: ajb
author_rank: Super Contributor
timestamp: December 05, 2019, 07:32:16 pm
content: Quote from: tom66 on December 04, 2019, 07:13:20 amThe kink (in either the signal pins or the mechanical pins) is there for retention prior to soldering. Lighter parts especially can be shifted during wave soldering, so the kink helps prevent that.QuoteI think you underestimate the amount of work in translating a manufacturer's catalog into digikey's catalog. There's a big old "Report an Error" button on every item page for a reason! (Mouser has one too, for the same reason)

author: typoknig
author_rank: Regular Contributor
timestamp: December 05, 2019, 08:58:23 pm
content: QuoteDo you think listing the part I linked to as having board locks is an error by Digikey then?

author: tautech
author_rank: Super Contributor
timestamp: December 05, 2019, 09:06:41 pm
content: You're confusing mechanical support with component retention prior to soldering.Without a bent pin or deformed clip components fall from the PCB should it be inverted or placed on the opposite layer for design requirements.

author: ajb
author_rank: Super Contributor
timestamp: December 05, 2019, 10:09:23 pm
content: Quote from: typoknig on December 05, 2019, 08:58:23 pmNo, I think it's perfectly reasonable to call kinked pins like that a "board lock" feature. There's no real standardized set of terms for features like that, though, so it's a question of translation across manufacturers (and users, and distributors) who may use different terms. Translation is always subjective.

author: typoknig
author_rank: Regular Contributor
timestamp: December 05, 2019, 10:36:20 pm
content: Quote from: tautech on December 05, 2019, 09:06:41 pmI understand what the physical features of the pots are used for, but if some people call an apple an apple and others call an apple an orange it makes it hard to have conversations about fruit. So I'm just trying to understand who is using what terminology and what that terminology means to them so I can get on the same page with the manufacturer and not end up with thousands of custom pots I can't use.

author: tautech
author_rank: Super Contributor
timestamp: December 06, 2019, 01:01:41 am
content: Quote from: typoknig on December 05, 2019, 10:36:20 pmUnderstood.Ok, if we apply the same terminology used for caps it’s snap in.Dunno if there’s a standard industry description and TBH use of through hole components are on the decline.Even some SMD use adhesives for component retention prior to soldering.IMHO the only way to identify pre soldering retention is to get the data sheet of if you’re lucky your supplier has this parameter in their online part selection pages.

author: Nusa
author_rank: Super Contributor
timestamp: December 06, 2019, 01:15:33 am
content: Quote from: typoknig on December 04, 2019, 07:04:46 amI can't say I'm terribly familiar with the phrase "board lock"...I'm guessing it's "board mount" in Chinese after being poorly translated to English.Anyway, your first example is a board-mount device...the sole mechanical support is provided by the board.Your second example is a panel-mount device...the primary mechanical support is provided by the panel it's attached to, and the board is secondary. That doesn't mean that six signal pins aren't a significant attachment, but they don't have to endure forces applied by the user.

author: tooki
author_rank: Super Contributor
timestamp: December 06, 2019, 03:26:40 pm
content: Quote from: typoknig on December 04, 2019, 07:04:46 amFirst of all, I don't think there's an industry consensus on the terminology. So just forget that idea to begin with.What I think is very telling is to look at the context of the terms used. If you look at DK's selection of pots, you'll see that "board lock" is NOT a parameter under the "mounting type", but under "termination", alongside solder lugs, pins, etc. So it's strictly referring to the electrical connection.The mounting type, on the other hand, includes panel mount, servo mount, surface mount, through-hole, and through-hole snap-in. The first pot you show would be a "through-hole snap-in", the second just "through-hole".But it's Digi-Key's terminology, since it's used across brands.Bear in mind that taxonomy is anexceedinglydifficult field, and one where there is rarely one "right" answer. Different manufacturers, distributors, user groups, etc. will use different, inconsistent terminology. (And that's just within one language, as an aside! What gets REALLY hairy is when different languagesgroupthings differently. You can't even just translate the different nodes on the tree because the actualshapeof the tree differs! I encounter this all the time going between German and English. For example, it's made inter-language links on Wikipedia a horrible mess, because Wikidata is not especially good at handling such taxonomical disagreements.)Quote from: ajb on December 05, 2019, 10:09:23 pmTranslation?? Bourns and Digi-Key are both American companies, so they'd both be using English natively.Or do you just mean correlation/agreement/standardization of terminology among manufacturers/distributors/users?

author: ajb
author_rank: Super Contributor
timestamp: December 06, 2019, 05:59:00 pm
content: Quote from: tooki on December 06, 2019, 03:26:40 pmWell, there's english, and then there's english. Also, there's english, english, and don't forget english.I was sort of making a (very small) joke about different company- or industry-specific terminologies being analogous to languages/dialects, and english is a good foil for that. But jokes aside, I stand by translation as the most appropriate term because in many cases there isn't a one-to-one relationship between the set of terms used in one industry, industry sector, region, or company and another. One company's "board lock" feature might be similar to, but not exactly the same as, another company's "snap-in". Those features may be interchangeable in some applications, but not in others. This isn't really the best example, but I think it shows the idea. One or two words can encapsulate a broad swath of engineering details and assumptions, and if you, as the designer selecting parts for a project, layer your own assumptions about the equivalency of those terms onto the selection process it's very easy to miss an important distinguishing detail and wind up with something that doesn't work. It's the same reason you don't design around the headline specs in a datasheet--you have to dig into the detailed specifications and understand the operating parameters under which those apply. Anyway, the question in the OP isn't nearly that subtle, and really doesn't warrant such philosophizing about how we convey engineering data in 'natural' language, so I'll stop there