Best Quick Terminals

Discussion in 'General Electronics Chat' started by MrAl, Jun 17, 2014.

  1. MrAl

    Thread Starter Well-Known Member

    Jun 17, 2014
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    Hi,

    Recently i wanted to upgrade some of my quick terminals used for connecting wires to batteries like lead acid 7.5AHr or smaller 6v 4AHr types.

    I find that the wires break off of the terminal after a while of normal use.

    I'd like to find the best terminals made which take into account that the wire needs to be carefully attached to the terminal so it does not break off as easy.

    So what are the best terminals you've found so far?

    Note these are quick terminals, female, and they are sometimes called "F" terminals, 1/4 inch size, also called simply "Disconnect Terminals".

    I can show a pic if that's possible here.

    Thanks in advance.
     
    Last edited: Jun 17, 2014
  2. inwo

    Well-Known Member

    Nov 7, 2013
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    Open barrel type.
    There are inexpensive hand tools available.

    [​IMG]
     
    Last edited: Jun 17, 2014
  3. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
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    You want one with an "insulation crimp" like shown in inwo's pic above. The additional crimp band that goes over the insulation of the wire acts as a strain relief..
    BUT sliding shrink tubing over the terminal crimp area/wire insulation will offer far better protection vs just an insulation band.
     
  4. THE_RB

    AAC Fanatic!

    Feb 11, 2008
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    The battery terminals are flat "spade" lugs.

    What you need are female spade connectors with strain relief. If you can't find them with integral strain relief you can use the femals lugs with hard square plastic outer shell, and use some hot melt glue to make them support the wire after the crimp.

    Or a couple layers of heatshrink over the crimp like mcgyvr suggested. But commercial apps like alarms etc use the female spade connectors with square plastic outer shells;

    [​IMG]

    They give you something to wiggle and pull on instead of the wire.
     
  5. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
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    yeah..stop pulling on the wire to disconnect and you won't have that problem in the first place.. ;)
     
  6. Sensacell

    Well-Known Member

    Jun 19, 2012
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    I love these 3M™ Scotchlok™ T-Tap Disconnect connectors:

    1) Easy to install without stripping or fancy crimpers

    2) Right angle wire exit.

    3) Expensive!
     
  7. GopherT

    AAC Fanatic!

    Nov 23, 2012
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    Don't solder the wire to the bare metal spade terminals - the wire will break where the solder ends and bare wire stares if there is any repeated flexing.
     
  8. MrAl

    Thread Starter Well-Known Member

    Jun 17, 2014
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    Hi,

    Thanks for all the ideas. BTW, i dont pull on the wire though (he he) but yes that would break the wire too.

    I am currently looking at these other connectors and now have found a few other types too, very interesting. I also now found a type that mounts into PC board holes, which gives lots of flexibility on how i can use them to get a super strain relief setup.
     
  9. inwo

    Well-Known Member

    Nov 7, 2013
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    It's hard to beat the strain relief of these.
     
  10. #12

    Expert

    Nov 30, 2010
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    Of course, using a zip tie on the wire bundle reduces flexing, but I feel like we're repeating the obvious. Probably because I do this for my day job and you don't.
     
  11. bwilliams60

    Active Member

    Nov 18, 2012
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    Not sure who uses these or where you would use them but they are one of the worst connectors ever created:
    1) Tends to cut wires being joined created a voltage drop
    2) Sometimes does not make good connection
    3) If exposed to elements, corrosion easily invades copper and bulky in wire harnesses
    Proper wire repair should not require the use of these
     
    shortbus likes this.
  12. #12

    Expert

    Nov 30, 2010
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    I'm with bwilliams. I hate those connectors.
     
  13. inwo

    Well-Known Member

    Nov 7, 2013
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    I always thought they were pretty neat.

    Now that I think of it. The last one I used, wire was too short to cut on a mower, it failed.

    On further thinking, all my experiences with them have been bad.:(
     
  14. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
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    Scotch Locks work decent "when used properly".. BUT Most don't pay enough attention to the size/wire limits or to ensure that the wire is seated in the terminal opening properly before squeezing it all down or use a hammer on it or whatever..
    That style of connection is called an "insulation displacement connector" (IDC) and should just cut through the insulation and "funnel" the wire down safely between the terminal.

    But the OP wants "quick disconnect" and they are Scotch locks are not. ;)
     
  15. MrAl

    Thread Starter Well-Known Member

    Jun 17, 2014
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    Hi,

    What wire bundle, who said wire bundle?

    I am talking about one single wire, one single Faston connector.

    I am not happy with the standard crimp wire and crimp insulation like that shown in the post just before yours. I wanted something extremely durable.

    In my case, the wire may move around a little so it has to be super rugged, and there is nothing to tie wrap to.

    Thanks to all for the ideas, and the more the better :)
     
  16. #12

    Expert

    Nov 30, 2010
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    Here. You can use this one with only one wire.
     
  17. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
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    As already stated just apply shrink tube over the terminal barrel after crimping.
    Also make sure you are using a proper crimp tool as that can have an effect on crimp reliability. Don't just use needle nose pliers,etc.. and don't solder it.
     
  18. MrAl

    Thread Starter Well-Known Member

    Jun 17, 2014
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    Hello again,

    #12:
    I have a feeling you have a good idea, but you'll have to clarify how you want to use the tie wrap. You mean tie wrap the wire insulated part to the connector after soldering it on, as in fold it over, or something else?

    mcgyvr:
    Well, i need to solder the wire onto the connector. Shrink tubing will help yes, but it's not enough for my purpose. I want a physical strain relief of some kind.

    I've attached an illustration of one way to do this, but it's just one way im sure there are other ways or better terminals to begin with.
     
  19. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
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    huh? its a crimp terminal.. why are you soldering it?

    "IF" shrink tubing and a crimp terminal with insulation crimp is not suitable then you need to find a different style of connector. Faston is just NOT for you then. There is clearly something you are not sharing with us about this connection.. Those connections should be MORE than sufficient.. Come on.. let out the secret.

    If you give more details (wire size/use,etc..) on this connection I would be happy to suggest a suitable connector with appropriate strain relief.
     
  20. MrAl

    Thread Starter Well-Known Member

    Jun 17, 2014
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    Hi,

    I appreciate your reply and also hope that #12 gets back with a better explanation of how he can use the tie wrap. I have plenty of tie wraps of various sizes, and have actually used them on connectors, but they were much bigger alligator type 'connectors' not really connectors. There were no strain reliefs at all on the large alligators, so i used tie wraps. These little Faston's are quite small however, so i'd like to hear how he would like to do it. I guess there might be some way to thread the tie wrap in there somewhere before or after soldering.

    The connector MUST be a female that mates with a male Faston terminal that is typically found on lead acid batteries around 7AHr or so.

    I want to solder the wire to the terminal. For one thing, i like to reuse the terminal even if the wire breaks off, and crimping does not allow this. There's no secret here.

    The wire size can be 18 or 16 AWG, insulated, stranded, more than 7 strands per wire that make up the full wire gauge.

    I thought about using test lead wire, but the insulation is too thick so i am using regular stranded wire with regular insulation.

    The application is to connect to a lead acid battery to a drill, where the wire is connected and disconnected every so often, and the wire moves around a little as the drill is used although not too much. I want to use the Faston terminals because that is what the battery has, and this isnt the only battery i will be using with it so i dont want to have to retrofit the terminals on every battery i have.
    The batteries will also be used for other purposes so i can not solder new terminals to the battery male Faston terminals either.

    To provide an idea of the stress related to the terminals, the wire breaks now and then with a good crimp or solder and crimp, but the male terminal on the battery never bends or gets damaged in any way. The wire holds up longer when the wire is wrapped around a regular female Faston connector at a 90 degree angle and then soldered, rather than pushing into the normal 'sleeve' and crimping or soldering and crimping. That could be because of the way the wire lays when it is being used, at roughly 90 degree angles to the battery itself. With a standard crimp the wires come out of the terminal and have to bend at 90 degree angle to the connector, but with a built in 90 degree bend they come out straight so there is little side to side wobble, most of the direction of the stress would be straight out along the length of the wire, and in that way all the strands get roughly equal stress.

    I am open to other ideas though. For example, another type of connector mounts in a PC board. I could solder them in to a small board then thread the wire through the board holes a few times, which would work really well. I dont have any of those type yet so i am working on other ideas first (i have heavy duty angled connectors already but would like to improve upon the connection to these as well).
     
    Last edited: Jun 20, 2014
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