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I need to decide what connector to use on my PCB to connect low power wires. Among the available options on Farnell/Mouser etc. The price and size are almost similar.

I wonder if using a screw terminal or a push-in terminal would be better for a vibrating environment?

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    \$\begingroup\$ I would say screw with some loctite around. but anyway, route and fix your cables in such a way the relative vibration between them and the connectors will be minimal.. \$\endgroup\$ – Eugene Sh. Jan 28 '16 at 15:35
  • \$\begingroup\$ What type of vibrations (frequency, intensity)? Generator, highway vehicle, offroad vehicle, ultrasonic cleaning station? \$\endgroup\$ – SpaceCowboyMDK Jan 28 '16 at 15:35
  • \$\begingroup\$ In either case, provide a tie down so that you minimise fatigue which is better absorbed in the length of cable \$\endgroup\$ – ChrisR Jan 28 '16 at 17:49
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Push-in or 'cage-clamp' terminals have been around for several decades now and are a reliable solution for connections in general and vibration-proof contacts in particular. Some of the electricians where I work still prefer the hand-tightened screw terminal but some of our machine builders have switched to cage-clamp, where possible, to eliminate problems with terminals vibrating loose during road transportation.

Cage-clamp terminals are made by many companies.

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Figure 1. Wago cage-clamp terminals.

Some of the terminals require a 'just right' screwdriver to release the cage properly. (Some screw terminals require the right tool too.)

Cage clamp and wire

Figure 2. Cage clamp and wire showing excellent contact area.

(Photos used previously in my answer to another question.)

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For most cases, your most vibration-secure (won't easily lose contact), after taking already-mentioned strain-relief & vibration-damping steps, will be one of the "latching" plug-in types, like the ATX & IDE power connectors inside a desktop/server computer case (and most connectors in automobiles as well). The (external to the circuit contacts) latch keeps the connection pins from "backing out" under most any strain that doesn't break the latch.

EDIT: For clarification, I mean something like this: connector pic 1
or this: connector pic 2
images credit molex.com, http://www.molex.com/molex/products/group?key=wire_to_board_connectors&channel=PRODUCTS&langPref=english

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  • \$\begingroup\$ Look at the photos in the OP. He's using PCB soldered terminals. You're answer as it stands is not relevant to the question and doesn't address his question of screw or push type. \$\endgroup\$ – Transistor Jan 28 '16 at 18:11
  • \$\begingroup\$ ...added example images of PCB soldered terminals, similar to OP photos. \$\endgroup\$ – Robherc KV5ROB Jan 28 '16 at 18:34
  • \$\begingroup\$ They're photos of plug connectors but OP isn't using plugs. He's wiring directly to fixed terminals in the PCB. Your answer is about latching connectors (which in all your examples use crimp pins). OP doesn't want crimps. OP wants screw or cage-clamp terminals for stripped wire ends. \$\endgroup\$ – Transistor Jan 28 '16 at 19:11
  • \$\begingroup\$ @transistor However, the OP can solder plugs on the wires, right? :) I see this answer as one that provides a good alternative. \$\endgroup\$ – yo' Jan 28 '16 at 19:28
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For high frequency, I would recommend push in. You cannot secure the screw terminals with vibra-tite, loctite, etc. so they could very possibly shake loose.

For high impact (like an off road vehicle), I would say either is safe but to Eugene's point, secure the wires so they do not add strain to the termination.

I would also mount the system on rubber pads/washers to minimize vibrations that might be damage sensitive components like crystals and oscillators.

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    \$\begingroup\$ add the above comment to your answer using the edit function \$\endgroup\$ – KyranF Jan 28 '16 at 16:39

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