Does a DIN rail have to be a U shape? - Page 1
Forum section: electronics / general

author: e100
author_rank: Frequent Contributor
timestamp: February 03, 2023, 03:11:56 am
content: Are there any modules that expect there to be a void behind the mounting plane?Would a simple shape like this work just as well for the vast majority of things with DIN rail mounts?

author: ataradov
author_rank: Super Contributor
timestamp: February 03, 2023, 03:23:38 am
content: There are a lot of things that use this space, but I don't know how compatible they are to the actual standard. But they do exist in practice, so it is worth accommodating them.Examples:https://www.sourceasi.com/product/din-rail-knife-disconnect-terminal-block-green-lever-20-12awg-5-5mm-3/?ref=isp_rel_prd&isp_ref_pos=4https://www.camdenboss.com/camden-boss/cdr-bracket-din-rail-mounting-bracket/c-23/p-16624https://www.adafruit.com/product/4556I have not seen big modules needing it, but I think a lot of small ones rely on it for additional support.

author: e100
author_rank: Frequent Contributor
timestamp: February 03, 2023, 04:46:25 am
content: Quote from: ataradov on February 03, 2023, 03:23:38 amInteresting. These all appear to be designed to fit multiple sizes/shapes of DIN rail (top hat, mini top hat and G-section) using a series of nested slots. It looks like you should be able to cut out the redundant parts without compromising the integrity of the unit as a whole.

author: ataradov
author_rank: Super Contributor
timestamp: February 03, 2023, 04:59:56 am
content: Then there are things like thishttps://www.auberins.com/images/DRCN_profile.jpgwhere it may be actually functional. Or at the very least it would be quite an undertaking to remove it. For contractors this form factor seems to be very wide spread.Even in Adafruit case, it look like the width of the mount is at least 15 mm. And the geometry is not very accessible. Cutting all that out is not going to be fun.

author: e100
author_rank: Frequent Contributor
timestamp: February 03, 2023, 05:45:08 am
content: Quote from: ataradov on February 03, 2023, 04:59:56 amContactors do look to be a problem. The 'keep out' plane appears to coincide with the rear face of the 1.5mm thick metal DIN rail.For the other however, the oscillating multi tool comes to the rescue, wood, nails, dry wall, plumbing, electrical....anything

author: tooki
author_rank: Super Contributor
timestamp: February 03, 2023, 06:15:33 pm
content: Quote from: e100 on February 03, 2023, 03:11:56 amI think it’s quite common for them to intrude into the void, since that does appear to be part of the standard. (I also wonder what you mean about a “simple shape” like you’ve drawn: from a manufacturing standpoint, yours is a much more difficult shape to manufacture.)

author: e100
author_rank: Frequent Contributor
timestamp: February 03, 2023, 08:09:05 pm
content: Quote from: tooki on February 03, 2023, 06:15:33 pmYou're thinking folded sheet metal, whereas I'm thinking 2 pieces of rectangular stock metal/wood/G10/whatever joined together. No bending required.

author: KaneTW
author_rank: Frequent Contributor
timestamp: February 03, 2023, 08:55:46 pm
content: Check the standard. There's no requirement for the particular top-hat shape that's commonly seen on steel rails. Instead, there's a general standard and an annex for steel specifically:As long as you fulfill these requirements you're good.Also consider the loading requirements vs screw distance. For standard steel rails:For other materials, you need to do the math yourself.

author: ataradov
author_rank: Super Contributor
timestamp: February 03, 2023, 09:09:50 pm
content: Quote from: KaneTW on February 03, 2023, 08:55:46 pmSo, it looks like you will be choosing between compatibility with wide variety of practical modules, and raw standard compatibility.There are DIN mounted products from reputable vendors that would not mount on the solid rail. Here is a relay socket from Siemenshttps://www.mauriceelectric.com/siemens-3tx7144-4e2-8-pin-touch-safe-relay-socket-din-rail-panel-mountThe screw mounting shrouds would interfere. And this seems to be a very common design for relay mounts, they all look about the same.In practice, the market has spoken and what is generally understood under DIN-rail is the bent channel design. And I personally have never seen anything else.

author: KaneTW
author_rank: Frequent Contributor
timestamp: February 03, 2023, 09:53:08 pm
content: Yeah, I've never seen a non-hat profile DIN rail either. Actually, I saw one when googling earlier that was out of plastic and had ribs on the inside. Never seen one used though.

author: H.O
author_rank: Frequent Contributor
timestamp: February 04, 2023, 12:07:32 am
content: Standard compliant or not - IME simple relay sockets and such might fit on a flat rail but signal isolators, converters, monitoring relays etc might not. Either because they are compatible with BOTH 30mm AND 15mm DIN-rail OR because they might be relying on "the void that's usually there" for a power/comms busbar sort of thing (PR Electronics for example).