Joining 2 PCBs for outdoors - Page 1
Forum section: electronics / beginners

author: abit
author_rank: Contributor
timestamp: May 02, 2015, 02:55:48 am
content: Anyone knows of a through-hole size connector which is suited for this? There is only 2 or 3 contact points needed, but it should preferably 'condensation' proof, by which I suggest it will not saturate to a point to conduct by any 'significant' amount, or rapidly corrode? This would be for a PV assembly on one PCB, and the storage circuit on the second. It should also be good for locking two light-weight PCBs - so releasing the assembly would not require latches or bolts? Of course, no gold-contacts or really high-level products for signaling or such... Any idea of obvious choices for this? Thanks!

author: T3sl4co1l
author_rank: Super Contributor
timestamp: May 02, 2015, 05:22:49 am
content: If a condensing environment is expected, won't that be worse for the components on the board than the connectors between them (and other things)?Are you looking at conformal coat, then? ($$$)An IP67 enclosure would be quite safe, but ($$$)...Tim

author: Refrigerator
author_rank: Super Contributor
timestamp: May 02, 2015, 05:24:18 am
content: Quote from: T3sl4co1l on May 02, 2015, 05:22:49 amOr you can get a can of spray paint or spray laquer to give it a coat.

author: abit
author_rank: Contributor
timestamp: May 02, 2015, 05:43:34 am
content: Well, I assumed 'condensation' and other concepts in my hobbyist mind is about the same as in pro minds.The PV side has nothing but the PV and two terminals (a third for short-circuit the PV for testing, optional). Not environment sensitive, the PVs are sealed glass pieces, low voltage and may be drenched in rain or snow.The storage side is the same. The ceramic capacitor bank is protected by a diode (from reverse-discharge through the PV) and low voltage enough for rain and snow.The connector, on the other hand should not take in water (ice will crack it, salt will corrode it, all of this will increase resistance to the point of no conduct).This is only a design, so please keep shooting holes through it, I truly appreciate it, I mean it.

author: Rerouter
author_rank: Super Contributor
timestamp: May 02, 2015, 05:59:30 am
content: Lets assume full outdoor exposure, and the connectors are the only part exposed, jut to rule out the rest of the issues that come with having a board living in rain water.if it is purely power, (assuming + and -), then why not use solar panel connectors, yes they are a bit pricy, but they do there job, join external to your enclosure, and use a gland or similar for wire entry,if you want it to be the PCB mounted connector that is water proof, then your playing the harder game, as most products are not designed with that in mind, the only time i have seen something similar was with M14 connectors, on a really ruggedised video system, (miltary connectors if pretty much where your dipping your toes anyway)

author: abit
author_rank: Contributor
timestamp: May 02, 2015, 06:06:35 am
content: Thanks again, the options seems very limited. I just needed to have some idea about that.

author: Rerouter
author_rank: Super Contributor
timestamp: May 02, 2015, 06:12:56 am
content: ok, flip side, create 3 6mm plated through holes and surrounding space for stainless steel washers, Coat the rest of the board in a resin or similar leaving just the bolt holes exposed to the outside worldbolt the 2 boards together using nylon nuts and seal in self amalgamating tape around the join and done, it will be a little awkward if you need to re-do the connections but the tape means its easy to reseal afterwards,

author: abit
author_rank: Contributor
timestamp: May 02, 2015, 08:13:58 am
content: That is something I was considering before, but I was thinking of 2 bolts on opposing corners - granted, the open corners and the center of the two plains would not hold the same as the bolted down corners.The problem as it seems is really academic, there is no practical solution to this, but it never hurts to ask...

author: Ian.M
author_rank: Super Contributor
timestamp: May 02, 2015, 09:20:24 am
content: Some of the connectors commonly used in high power RC model applications will stand up to that sort of usage and conditions *IF* properly installed and protected. E.g. a normally cable mounted bare bullet connector system likehttp://www.integy.com/st_prod.html?p_prodid=15802&p_catid=174, mounted by soldering into a close fitting plated through hole, with a sleeve of thick wall silicone tubing over the female connector, long enough to compress slightly and seal against both PCBs when fully mated + initial packing of the connector with silicone dialectric grease. Obviously the PCBs will need to be properly protected - e.g. epoxy coated everywhere except immediately round the connectors.

author: jay
author_rank: Regular Contributor
timestamp: May 02, 2015, 02:42:43 pm
content: How much current flows through the connector? Voltage?

author: abit
author_rank: Contributor
timestamp: May 09, 2015, 03:43:19 am
content: How much current?!Micro, nano. A 1000uF capacitor bank may only allow that much, and I am currently considering an SO-8 package of LTC1540 in COMPARATOR mode to the PV output - to swing when the PV is over/under 2.2VDCHere are my issues - I cannot deal with anything smaller than full-size SOT-23, no smaller pads and the pads and leads must be exposed. No QFN or other packages, made principally for SMT placement.Everything else comes down to scaling and experiments... cost of circuit is not an issue, it is a learning experiment... thanks for posting!