Enclosures for humid or damp environments

Does anyone have any advice regarding external enclosures?

I’ve been making a couple of solar powered soil sensors with Xenons, one for the garden one for the greenhouse. I need to make an enclosure to protect them, but I am also doing environmental monitoring including humidity. Clearly that will not work if I go for a high IP rating.

I was going to design print the enclosure myself. If I have the xenon and battery in an enclosure with vented sides, is it likely to last long? Or, is it better to go for a split thing where the humidity sensor is in a vented part and the rest of the project in a more sealed section with the wires running out? I did wonder if I go for the latter if there are any over heating issues to consider or if any moisture does get in it will not dry out as easily. I’m in England where we specialize in drizzle.

If you mean having your humidity sensor inside your IP rated enclosure - correct.

I am in England as well - I have a Photon controlling my driveway lights - it is sat inside a commercial IP rated junction box from ScrewFix with sealed/gland wire entries from sensors - no overheating issues and no other issues for the past 2 years that it has been working.

Depending on the size of the project, this might also work? Handy with a Feather PCB included as well.

Yeah, that is it. I didn’t know if I should split the project into two boxes, one protected and a vented cover for the sensor, or just vent the whole lot.

Thanks, that does look good.

Hi Dave,
could a sensor like this one help you?

I used to work for a company where we made our own remote telemetry equipment, stuff that went into some pretty terrible environments. There were a couple of things. This makes me think cause I actually want to build a simple little weather station for myself. TBH I was just going to poke a hole in the bottom of an electrical box and call it a day.
The first was that all the equipment PCBs were conformally coated. I wonder if you could get some kind of conformal coating in a can. To be honest, sometimes small parts were just encased in silicone. Even if you could spray everything with a thin layer of silicone that would be alright.
The second part was that for remote sensors the sensor was separate from the electronics. So ya, like a sealed housing with a sensor coming through to measure what it had to measure.

Point of interest on this topic. For the sensors which went into really tough environments, we found that if the housing was completely sealed it would actually fill up with water. The only thing we could think of was the constant heating/cooling cycle of it being in the sun, maybe some humidity permeating and then condensing. The only solution was to use a little vent made of some kind of GORE-TEX which let moisture go only one way.