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I have 4 wires 10AWG stranded, that I need to connect to a PCB that I'm designing. They will be in a high vibration environment, so direct through hole soldering may not be the best solution.

I've thought about ferrules, but those are usually used with screw terminals, which are also not ideal for high vibration env. I've also thought about crimping the ferrule onto the wire and then soldering the ferrules to the PCB, but I can't find any information on that idea, good or bad.

What other options are there?

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    \$\begingroup\$ Can you be more specific about what high vibration is exactly? Magnitudes and frequency would help. \$\endgroup\$ – Ron Beyer May 6 at 1:14
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    \$\begingroup\$ Solid or multicore wire? \$\endgroup\$ – Ocanath May 6 at 1:16
  • \$\begingroup\$ Would metal grommets provide a stronger attachment? \$\endgroup\$ – DrMoishe Pippik May 6 at 1:24
  • \$\begingroup\$ Does this answer your question? How to connect 50 A 12AWG cable to a shunt resistor in PCB? \$\endgroup\$ – DKNguyen May 6 at 1:24
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    \$\begingroup\$ @Aaron Just toss in some threadlocker. Or jam nuts. Or lockwashers. Screws are used in high vibration environments all the time. It's not like solder joints don't suffer from fatigue. \$\endgroup\$ – DKNguyen May 6 at 17:53
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My general strategy for dealing with vibrating wires is to provide strain relief. I would consider adding holes in your PCB specifically for wire retention, like in the image below. You can use superglue or a potting compound to adhere the wire to the PCB to further prevent the solder joint from vibrating and failing.

enter image description here

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    \$\begingroup\$ I had no idea that was the purpose of those extra holes! \$\endgroup\$ – PeterT May 6 at 17:17
  • \$\begingroup\$ I've done this before for small wires, but 10AWG might require more room than I have. I'll have to investigate the allowed bend radius. \$\endgroup\$ – Aaron May 6 at 17:19
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    \$\begingroup\$ you could also lay the termination point flat so the wire is parallel to the plane of the board, reducing the required bend radius \$\endgroup\$ – Ocanath May 6 at 17:22
  • \$\begingroup\$ @Ocanath "...lay the termination point flat..." I think I like that the best. \$\endgroup\$ – Aaron May 6 at 17:28
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    \$\begingroup\$ A point I'd consider is that the wires are so inflexible that they will place quite a bit of stress on the board as the assembly is manipulated into place. Consideration must be given to somehow re-enforcing the board (or using a stronger board material) to avoid damage. \$\endgroup\$ – Hot Licks May 7 at 16:30
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Ferrules on each conductor, then into spring cage connectors on the PC board.

I do a lot of work on very large earth-moving machinery and the field techs tell me that connections done that don't ever fail.

I've since started using those spring-cage terminals on some of my products and have had zero failures since going to them.

The following link shows Phoenix rail-mount terminal blocks but will allow you to find PC mount variants.

https://www.phoenixcontact.com/online/portal/ca?1dmy&urile=wcm:path:/caen/web/main/products/subcategory_pages/Spring-cage_connection_P-15-03/c252a030-3764-4828-a692-d0ba1dd45a27

Sorry for not enclosing the link in the proper hyperlink format but I can't find how to do that on my new phone.

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  • \$\begingroup\$ it is nicer to see the URL in its entirety \$\endgroup\$ – jsotola May 6 at 3:12
  • \$\begingroup\$ I poked around on their site, but when I get to PCB mount, I don't see "Spring-cage" that can handle 10AWG or 5mm^2. \$\endgroup\$ – Aaron May 6 at 17:26
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    \$\begingroup\$ phoenixcontact.com/online/portal/ca/… not sure if this is spring cage though \$\endgroup\$ – Yet Another User May 6 at 22:12
  • \$\begingroup\$ @YetAnotherUser Yes, that's push-lock spring connection. \$\endgroup\$ – Mast May 7 at 11:10
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Can't you just use a Faston? They'll do AWG 10.

PCB Part Wire part

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    \$\begingroup\$ Probably cheapest and simplest option available. Just a couple notes: first, look for terminals with special lock notch in the middle (not all of them have it). These will not disconnect from vibration, in fact they are quite hard to remove manually after installation. Second, I'd recommend using insulated connectors marked "double crimp". These are used with special crimping tool that compresses plastic insulation around wire jacket, creating sort of additional strain-relief. In fact, you can put your own strain relief (e.g. shrink wrap) on the wire and crimp over it. \$\endgroup\$ – Maple May 12 at 20:17
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I used to work in a lab that tested high speed cables. These cables were much thinner than what you're dealing with, but you may be able to use the same technique for strain relief.

We would zip-tie the cable to the PCB an inch or two away from where it needed to terminate and then solder the wire to surface-mount pads on the PCB. The zip-tie passed through holes in the PCB and wrapped around the cable

Here is a blurry picture of how it was done:

Cable strain relief

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Spring loaded terminals are one option worth considering. This really depends on the vibration strength.

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depending on vibration strength, you might probably want to consider pcb mounted circular connector. might be expensive depending on size and number

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A terminal block is a pretty normal way to get big wires onto boards. They come in a dizzying array of shapes, sizes, styles, etc. If you don't like the spring clamp or screw terminal types, there are also ring terminals of a variety of types, etc. Whether you choose something like this depends on whether or not the wire ever needs to be disconnected again (service, replace parts, user connection point, etc).

enter image description here

enter image description here

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How high is high vibration?

My default answer would be to use an appropriate connector. There are many good, high current options.

Spring loaded contacts from Wago, Phoenix Contact, and others are available in this wire size. Watch the current ratings carefully. Many of these have surprisingly low current ratings for larger wire sizes.

You might also consider a locking Faston - these have a locking tab that goes onto the hole on the tab. You could also consider riveting a ring terminal to the board. You could even reflow it after it's riveted. It all depends on your application.

10AWG implies pretty high current. How are you getting the current capacity in a board as small as you imply?

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