Electronics > Projects, Designs, and Technical Stuff
are wire nuts vibration resistant?
<< < (5/7) > >>
CatalinaWOW:
Safer under what circumstances?  Carrying current enough to melt wire insulation isn't good enough?  Surviving many, many newtons of pullout force?  Is there a source for this concern about the safety of wire nuts?  What is the failure mode and what is the failure rate?

I do agree with the concern about buying low quality copies of ANY configuration. 
james_s:
There is no issue whatsoever with wire nuts. For some reason there are a few people in UK/Europe who don't like them, most of those people clearly having only seen pictures and never used one. As with any connector type it's possible to improperly install them, but used correctly I find wire nuts to be the most mechanically secure device available. If you need to repeatedly connect and disconnect then a screw clamping terminal block is superior but for more permanent connections a wire nut will hold the wires more securely and be more resistant to mechanical issues or loosening of the screw. I've never had a wire nut fail in my house, I have however had the screw clamp on a circuit breaker fail. It loosened up somehow over time and arced.
coppercone2:
How about the repeated cooling and heating of the wire nut causing it to loosen some how? Is that possible?

In my mind a crimp is deformed mechanically so much that the effect is small. With a wire nut I am not sure, it seems mechanically different. Can it 'walk' off?

Say it heats, some area loosens and oxidizes a bit, then when it tensions again from cooling the stresses are different because of the oxide layer. Then it keeps happening. I think a mechanical crimp avoids this by being gas tight.

Say its exposed to a bad gas like H2S or something.
Monkeh:

--- Quote from: james_s on November 04, 2018, 10:41:40 pm ---There is no issue whatsoever with wire nuts. For some reason there are a few people in UK/Europe who don't like them, most of those people clearly having only seen pictures and never used one.

--- End quote ---

And then there are those of us who have.

I also don't like your plug design, outlet and box construction, breakers, voltage.. And yes, I have experience with using all of those, too.
CatalinaWOW:

--- Quote from: Monkeh on November 04, 2018, 11:12:36 pm ---
--- Quote from: james_s on November 04, 2018, 10:41:40 pm ---There is no issue whatsoever with wire nuts. For some reason there are a few people in UK/Europe who don't like them, most of those people clearly having only seen pictures and never used one.

--- End quote ---

And then there are those of us who have.

I also don't like your plug design, outlet and box construction, breakers, voltage.. And yes, I have experience with using all of those, too.

--- End quote ---

All connectors fail occasionally.  Either due to improper installation, manufacturing defect, or whatever.  What are the failure rates?  Anecdotal information is not data. 

Thermal expansion and contraction is an issue for any connector design.  Some designs have an explicit and fairly free floating spring to deal with this.  Others have a more implicit spring action.  Screw terminals and wire nuts are in this class.  Crimp joints have little if any.  All of the connector types mentioned in this thread form a gas tight seal.  Some with more area than others.  Some with some control over the pressure exerted.  There are reasons to hypothesize failure for all of these, but I don't have any information on the actual fielded failure rates.  There is also reason to expect those failure rates to vary regionally due to climate and construction differences.

I would really like to see engineering data rather than prejudice.  I am uncomfortable with some aspects of European wiring, but readily admit that my discomfort is driven more by unfamiliarity than facts.
Navigation
Message Index
Next page
Previous page
There was an error while thanking
Thanking...

Go to full version
Powered by SMFPacks Advanced Attachments Uploader Mod