Reliability of pin header/socket inter-board connector? - Page 1
Forum section: electronics / projects

author: RogerThat
author_rank: Regular Contributor
timestamp: September 21, 2023, 08:35:21 pm
content: Hi all,As the headline says, how reliable are standard single line pin and header connectors(as you find on for example the Arduino uno)?The final product I'm working on will be subject to lots of heat cycles and vibration.

author: floobydust
author_rank: Super Contributor
timestamp: September 21, 2023, 08:44:58 pm
content: Expecting the headers "to hold it all together" is the maker way, too Arduino lol.Are your boards bolted together, spacers etc? It's best to have no connectors at all between boards for highest reliability with vibration, temperature, moisture.The chinese header strips are total garbage - single cantilever spring, unknown plating and the plastics are a disaster. Poor tolerances and they quickly age and get brittle. Are you planning to use cheap shit?If you purchase name-brand headers like Samtec you will have much fewer problems. But many other factors apply, such as the mounting of the boards to each other and the enclosure, and the mass of the boards, cables wiring harnesses etc. as far overall vibration.

author: SiliconWizard
author_rank: Super Contributor
timestamp: September 21, 2023, 08:59:28 pm
content: Quote from: RogerThat on September 21, 2023, 08:35:21 pmNot much at all unless the device is guaranteed to stay untouched, under no vibration, for its lifetime.So either use means of bolting the boards together, or use different connectors with a locking mechanism, connecting boards via wires/flat cables to give some relief.Note that the more pins header connectors have (in a single block) and the harder it is to separate them (due to increased friction), as you might expect. So if you absolutely have to use pin headers, use blocks with the highest number of pins possible for your design, dual rows better. Say if you have to connect 40 signals between boards, it's better to use two 2x10 pin headers placed symmetrically than to use a number of separate pin headers. But don't use that for harsh environments.

author: RogerThat
author_rank: Regular Contributor
timestamp: September 21, 2023, 09:02:43 pm
content: Thanks for the answers.The connectors do not take any mechanical load and I'm thinking of using only gold plated top tier parts.I was thinking initially to solder the boards togheter(with pins only) but this have little give in case for thermal expansion, the connector will allow for some movement without stressing the solder joints.

author: RogerThat
author_rank: Regular Contributor
timestamp: September 21, 2023, 09:05:24 pm
content: The boards (sandwiched) have 2.54mm pitch 9p connectors at the moment. There is a distance of 11mm between the two boards. What would be the best way of connecting them?

author: ConKbot
author_rank: Super Contributor
timestamp: September 22, 2023, 05:30:19 am
content: It really depends on the parts. If you pay samtec the stack of cash for ELP qualified "tiger eye" sockets with heavy gold plate on both contacts, it's be fine "forever"If you get the "sort by: price, ascending" special from aliexpress not so much. As an example of this, I have a coworker that loves XT-60 connectors from various rc hobby gear. But when you try to solder them, the edges of the solder wetting the metal show bare copper, despite them being gold plated. What this tells me it's that they are *just* gold plated with no nickel under layer. (https://www.finishing.com/library/stransky/nidifbar.htmldetails on why it's needed, and also talking about how bulk material diffusion happens at 200C ish, explaining why I'm seeing bare copper after soldering) some bargain bin headers with plating of that quality are certainly prone to intermittent failure in time.

author: ArdWar
author_rank: Frequent Contributor
timestamp: September 22, 2023, 08:00:08 am
content: Samtec header with TigerEye contact is pretty reliable with shock/vibration. If you want a functional equivalent, try to get similarfull ringcontact with multiple spring wipe. Avoid fork style contact!I don't really know about their longevity or heat/UV/oil resistance however. They list the plastic as "liquid crystal polymer", what exactly was that even? That's way too wide grouping.