Electronics Box with IP68 rating

[mechEhere]

I need to design a box that will enclose some electronics. The box needs to be IP68. I am thinking of just placing potting compound in the box to seal/enclose the printed circuit board. Anyone familiar with a potting compound that can achieve this? Or is there a design reference guide on how to design a box for IP68? Thanks!

 

[itsmoked]

Run! Run screaming! Away from that idea. Wait till you see what potting costs these days and the nightmare of rework.


There are IP68 boxes out there. Look around.

http://www.industrial-enclosures.com/html/ip65-enclosure.html

http://enclosures.alliedmoulded.com...page/Ind_Home_Page/template/products_main_ind

What is your application type?

Keith Cress
kcress -

http://www.flaminsystems.com

 

[drawoh]

mechEhere,

I would think any potting compound will work, as long as it is not water soluable, and as long as it is applied properly.

According to my chart here, IP68 must withstand continuous submersion. I do not see a depth specified, but I recall it is something like 2[ ]meters for something like 24[ ]hours. Definitely, you should look it up. Your options are to buy an off-the-shelf IP68 compliant enclosure, or to build a 2m tank to test out your own design.

Find out how much heat you have to dissipate. A ventilation fan will not work, although a circulating fan might. Your electronics designers are going to have to co-operate with you, and at least tell you how much heat you have to dump.

JHG

 

[Tunalover]

Much depends on cost. You could mold the entire assembly into potting compound thus precluding a protective box entirely. The potted assy will be impervious to contamination provided there are no leakage paths through the potted compound (e.g. wires with inadequately etched jackets to promote adhesion with the potting). This concept means to throw it away and replace it when it breaks. If it's an expensive assy and you want to repair or service it then an IP68 box is the solution. Note that even an IP68 assembly is not immune to internal condensate; humidity will permeate the seals. To remediate that use a dessicant.


Tunalover

 

[drawoh]

tunalover,

Heat is still an issue. I used to own a Commodore[ ]64. The old Commodore power supplies were potted, and they used to fail. The reason usually given for this was that, as the components heated and cooled, the internal connections would rip apart. The C64 did not meet IP68, so there was no need for the power supply to meet it!

In the absense of standard, IP68 compliant components, you would have to test this thing. You have to assume that the OP's customer intends to submerge this thing.

JHG

 

[itsmoked]

But who knows since the OP isn't bothering to participate.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[Tunalover]

I wfasn't aware heat was an issue. It would be a fairly simple heat transfer problem to determine if the assy would overheat provided you know the internal power dissipation.


Tunalover

 

[drawoh]

tunalover,

I am the one who brought up heat. Unless there is a rotating shaft extending out of this thing, all the power that goes into it will be dissipated as heat. This potential problem is often ignored until it is too late. You cannot just put a ventilation fan on an IP68 enclosure.

Probably, heat is not a problem. This should be investigated before mechEhere does any design.

JHG