We used a PCB in an explosion proof enclosure. The side you connect to power and signal has to be physically isolated from the electronics and sensor. An FR4 board with solder mask is very waterproof. We put in a rubber gasket, made the board double thickness, and screwed it into the enclosure. It was a connector on each side, and ground plain to the screws.
Usually this was done by tapping holes in the aluminum enclosure, then screwing in sealed ferite beads and soldering them to a connector or a wire. Cost was huge, plus over tightening the bead would strip the threads out of the hole way to often.
One round board, and a soldered on connector had no leaks. I left the enclosure full of water for weeks, til it got stinky and I had to throw it out. Saved about $60+ per unit.
All of this stuff looks like enthusiasts/hobbists level manufacturing and it isn't clear if any of this has any kind of Nationally Recognized Test Laboratory markings.
Where required, and where the product is released for production (some of the stuff shown only made it to the prototype phase) the product has been approved and carries the necessary CSA and UL markings.
I put together the photos from stuff hanging around the lab, so it is mostly prototypes or stripped down to show the PCB without all the packaging around it.
Another neat module on DIN rail I've seen is the current sensor, It's just a current transformer and relay on the PCB, the actual current carrying wire just goes through the hole in the CT without touching the PCB.
Where do you get the DK5 and DK6 housings from ? (fig11 & 12), they seem really hard to get hold of , I have about 20 x DK5 but can't seem to get any more. (There is apparently a thicker version of the DK5 too.)
I love figure 9 ! , just yesterday I completed a (DIN rail mounted annunciator) PCB for a client that has only 9 leds and is 7" x 3" (It's a copy of an existing PCB they have) your approach is much more elegant.
Figure 8 is agreat way to use up all that spare real estate on a pcb panel. But you need the right brand of fuseholder, a quick look in my box of DIN bits shows it won't work on any of the fuesholders I have :<( but you have inspired for something else I can do with them.
=============== using the wasted rails on PCB panels ==========
Another "structural use" for PCB's , in addition to your excellent examples:. Make up some rails to use to hold cut tape on the PnP machine, (I've just included some on my most recent PCB panel) , does something useful with all the wasted rails on top and bottom, You can hold about 15-20 strips each ~ 100 smt parts in 8,12,16,24mm tape , (when you push the tape onto the 1.55mm pins, the tape stays put as the sprocket holes are 1.50mm) :
You make up a set of rails like a picket fence, the top and bottom rails just have 2.7mm holes , spaced at 4mm pitch , I make them 0.300" wide but it's not critical. Like this Ascii art:
O O O O O O O O O O <-2.8mm @ n x 4mm ______________________________________________________
The "pickets" are 7.5mm wide , and have some small holes on 4mm pitch, 1.25mm in from right edge (solder some 1.55mm diam millmax type pins in these later) , and also 2.7mm holes at top and bottom, positioned 5.0mm from right edge. make them a bit more than 400mm long (=100 parts on typical tape) Like this:
Another neat module on DIN rail I've seen is the current sensor, It's just a current transformer and relay on the PCB,
We have done several variations of those as well- funny I didn't think to include them.
Where do you get the DK5 and DK6 housings from ?
The DK5 and DK6s have been through several manufacturing iterations but are now made exclusively by Weidmuller. I doubt that any of their distributors would know about the housing and you would have to speak to Wedimuller directly in whatever country you are. They have ben superceded by many newer housings and I believe they are trying to discontinue them. We were Weidmuller's design facilty in Canada and were spun off. In fact we still (for the next 2 months) work out of Weidmuller's Canadian facility. We still manufacture the products that we originally designed, under licence (those devices in the photo are theirs).
(There is apparently a thicker version of the DK5 too.)
I (and the Weidmuller tech support guy downstairs) am unaware of any wider DK5 package. There was a company called Sensorpulse that made a "top hat" cover for the DK6 that would allow you to use taller components in the DK6. We did use that top hat on some designs and I think we still have stock.
I have about 20 x DK5 but can't seem to get any more
If you need a few more, I think I may be able to help- but if you are going into production you may want to reconsider.
Another "structural use" for PCB's , in addition to your excellent examples:. Make up some rails to use to hold cut tape on the PnP machine,
Interesting.Actually using the word "rail" makes me think of some of the unusual things I have used DIN rail for. Maybe there is another blog in that.
That power outlet cracked me up! Why was taht even on a pcb?
"Ours is not to reason why..."
As near as I can tell, the reasoning goes like this:
When you have a panel (in an industrial environment) there are times that you want a 120VAC outlet to power instrumenation. Often it is transient like when you need a 'scope for debugging.
I have seen panels with loose extension cords inside them for that purpose, but there are issues (agency approval for one thing). So it would be nice to have the outlet mount on a DIN rail. Also, given the environment, it is prudent to have a circuit breaker or earth leakage.I doubt that the outlet manufacturers would see enough volume to justify a different rail mounting enclosure, not to mention further agency approvals, so this became our niche.
Mounting the outlet on a PCB so it can fit in a housing then allows it to mount on a DIN rail. Figure 6 gives you an idea of the board mounted in a housing. The board in Figure 5 actually has an enclosure that completely encases it. It also has a rail foot or screw mounting option. In addition the connection to the outlet are brought out to screw terminals on the PCB so that the power can be wired to the top side of the board after all the modules have been installed in the panel. You can see the two 3-way black connectors on the top side of Figure 5 and the 6-way orange connector in Figure 6.
Well, there's a big enough market for DIN rail outlets that at least one more company, ASI, makes them. Another use for them is convenient outlets for devices within your machine that like standard electrical cords (such as PCs, monitors, and some power supplies) -- and DIN rail outlets are easy to mount.
One reason I use Phoenix DIN rail enclosures is that Phoenix Contact's availability is quite good through Mouser, Digikey, etc -- and we get pretty good pricing through our local distributor.
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