+ Post New Thread
Results 1 to 5 of 5
  1. #1
    Newbie level 3
    Points: 24, Level: 1

    Join Date
    Sep 2015
    Posts
    3
    Helped
    0 / 0
    Points
    24
    Level
    1

    DC cable with specific coaxial connectors

    I have a portable lithium ion battery pack that powers a LED headlight. It uses this cable. The headlight came with 4 cables, however 2 of them have already died, giving only a few months of use each. I know someone else who has gone through all 4 cables already.

    I am awaiting a response from the company to see if they will replace the wires. As a back-up, does anyone know anywhere I can buy a cable with those two connectors or how I can make one?

    Perhaps it would be easier to just shell out the $25 they charge for 3 cables.

    Thanks in advance!

    •   AltAdvertisement

        
       

  2. #2
    Advanced Member level 5
    Points: 9,792, Level: 23
    d123's Avatar
    Join Date
    Jun 2015
    Posts
    1,726
    Helped
    402 / 402
    Points
    9,792
    Level
    23

    Re: DC cable with specific coaxial connectors

    Hi. Have a (patient!) trawl through a supplier's connectors, and cables, pages, and maybe check the datasheets available for current rating.

    http://uk.rs-online.com/web/c/connec...rs-connectors/

    Not sure which part of the catalogue the other barrel jack connector would be in, but RS have a chat option where some-one can point you in the right direction for that.

    I don't understand how a cable with nothing more than two connectors at either end can die in a few months, unless it's being "cooked", so in my ignorance I'd suggest seeing if you can get hold of a datasheet for the cable/connectors you have. Unlikely - but is the section (mm2) too small for the load, or are those connectors not rated for the actual load? It seems unlikely, but you never know.

    If you buy the parts yourself, you will no doubt have to buy packs of 5 or 10 of each connector, hope they are simple to crimp/connect to the cable, and be forced to buy at least a few metres or 30 or whatever of cable no doubt, so it might only offset buying the $25 pack to see if the ones you make last any longer than a few months.

    - - - Updated - - -

    Just thought, a probably/possibly more likely failure is something silly like a loose connection betweeen the cable and a connector from flexing them. If you have the time and inclination I'd try to take apart a "broken" cable, to see where the fault is coming from. The audio connectors are (hard work sometimes) slip on/off or screw twist on/off, the barrel jack one I don't know but will no doubt be a similar method, unless they have been glued, which shouldn't really be the case. In the worst of cases, just use a cutter/Stanley knife or similar (keep hands and fingers very behind cutting direction) to cut one open and trouble-shoot.
    If it's coax cable, I doubt it's flimsy, but another point to consider, if the terminations on the broken cable are sound, is to try with a different type of cable which is more flexible, and if it has to be shielded there are quite a few "shielded pair" type cables available for power.


    1 members found this post helpful.

    •   AltAdvertisement

        
       

  3. #3
    Newbie level 3
    Points: 24, Level: 1

    Join Date
    Sep 2015
    Posts
    3
    Helped
    0 / 0
    Points
    24
    Level
    1

    Re: DC cable with specific coaxial connectors

    Quote Originally Posted by d123 View Post
    Hi. Have a (patient!) trawl through a supplier's connectors, and cables, pages, and maybe check the datasheets available for current rating.

    http://uk.rs-online.com/web/c/connec...rs-connectors/

    Not sure which part of the catalogue the other barrel jack connector would be in, but RS have a chat option where some-one can point you in the right direction for that.
    Quote Originally Posted by d123 View Post
    If you buy the parts yourself, you will no doubt have to buy packs of 5 or 10 of each connector, hope they are simple to crimp/connect to the cable, and be forced to buy at least a few metres or 30 or whatever of cable no doubt, so it might only offset buying the $25 pack to see if the ones you make last any longer than a few months.
    I will have a browse through the supplier's website.

    I was also hoping that the cable used with the headlight is common enough so that I can purchase perhaps better quality ones elsewhere. I have no experience with electronics at all (I am in the health field) so was hoping it would be a last resort. The most I've ever done is taking apart my laptop but that was with a step by step tutorial.

    Quote Originally Posted by d123 View Post
    I don't understand how a cable with nothing more than two connectors at either end can die in a few months, unless it's being "cooked", so in my ignorance I'd suggest seeing if you can get hold of a datasheet for the cable/connectors you have. Unlikely - but is the section (mm2) too small for the load, or are those connectors not rated for the actual load? It seems unlikely, but you never know.
    Looked through the box and coudn't find any datasheets. I will ask the company if they would email a copy.

    The battery's output is 8.4V and 1.2A. I don't know if that helps at all.



    Quote Originally Posted by d123 View Post
    - - - Updated - - -

    Just thought, a probably/possibly more likely failure is something silly like a loose connection betweeen the cable and a connector from flexing them. If you have the time and inclination I'd try to take apart a "broken" cable, to see where the fault is coming from. The audio connectors are (hard work sometimes) slip on/off or screw twist on/off, the barrel jack one I don't know but will no doubt be a similar method, unless they have been glued, which shouldn't really be the case. In the worst of cases, just use a cutter/Stanley knife or similar (keep hands and fingers very behind cutting direction) to cut one open and trouble-shoot.
    If it's coax cable, I doubt it's flimsy, but another point to consider, if the terminations on the broken cable are sound, is to try with a different type of cable which is more flexible, and if it has to be shielded there are quite a few "shielded pair" type cables available for power.
    I think you could be onto something. I should have been more descriptive. The cable didn't die completely. If I jiggled the 3.5mm connector at the battery pack, I could sometimes get a few seconds of light on and sometimes flickering light but nothing sustained. Jiggling at the barrel connector had no effect. As soon as I change to a new cable, the light works as normal.

    Unfortunately, I threw the failed cables out. I will definitely keep the next cable that fails.



    •   AltAdvertisement

        
       

  4. #4
    Advanced Member level 5
    Points: 9,792, Level: 23
    d123's Avatar
    Join Date
    Jun 2015
    Posts
    1,726
    Helped
    402 / 402
    Points
    9,792
    Level
    23

    Re: DC cable with specific coaxial connectors

    Hi, that really sounds like a loose connection (or a break in the cable more or less where that connector starts, or don't discount the battery side receptacle connections) if jiggling it gets it to work. The 3.5mm means the audio jack, doesn't it?
    Unless it's vital to have more than one spare cable I wouldn't bother buying more yet; at most trawl online catalogues in the meantime looking for alternatives, and if there's a next time, as you said, try opening the connecter to see - if that is the problem you could ask anyone you know if they could solder/crimp it properly for you.
    Some-one here might know the correct term for that adapter cable, you never know.

    - - - Updated - - -

    Maybe I'm being naļve, some things are mistakes and some are fail-1-day-out-of-guarantee manufacture, but perhaps the supplier is unaware that that cable fails in the field with what really does sound like abnormal frequency. An example situation, is that the brand farm out manufacture of the various parts to subcontracts, and the cables are badly finished but the seller/brand is unaware of this, but does have users who seem like brutes who have to constantly reorder cables that should last longer than a few months. :)
    - Does the LED headlight have a 1 or 2 year guarantee, maybe none? All the same, If you have the time or deem it worthwhile of your time, I'd be a helpfully complaining customer and inform the brand/seller that their cables fail somewhat frequently, quite honestly they may actually genuinely appreciate the feedback.



  5. #5
    Newbie level 3
    Points: 24, Level: 1

    Join Date
    Sep 2015
    Posts
    3
    Helped
    0 / 0
    Points
    24
    Level
    1

    Re: DC cable with specific coaxial connectors

    Quote Originally Posted by d123 View Post
    Hi, that really sounds like a loose connection (or a break in the cable more or less where that connector starts, or don't discount the battery side receptacle connections) if jiggling it gets it to work. The 3.5mm means the audio jack, doesn't it?
    Unless it's vital to have more than one spare cable I wouldn't bother buying more yet; at most trawl online catalogues in the meantime looking for alternatives, and if there's a next time, as you said, try opening the connecter to see - if that is the problem you could ask anyone you know if they could solder/crimp it properly for you.
    Some-one here might know the correct term for that adapter cable, you never know.
    When I read your last post about a loose connection, that's when a light bulb went off in my head. It really does sound like a loose connection.

    Quote Originally Posted by d123 View Post
    - - - Updated - - -

    Maybe I'm being naļve, some things are mistakes and some are fail-1-day-out-of-guarantee manufacture, but perhaps the supplier is unaware that that cable fails in the field with what really does sound like abnormal frequency. An example situation, is that the brand farm out manufacture of the various parts to subcontracts, and the cables are badly finished but the seller/brand is unaware of this, but does have users who seem like brutes who have to constantly reorder cables that should last longer than a few months. :)
    - Does the LED headlight have a 1 or 2 year guarantee, maybe none? All the same, If you have the time or deem it worthwhile of your time, I'd be a helpfully complaining customer and inform the brand/seller that their cables fail somewhat frequently, quite honestly they may actually genuinely appreciate the feedback.
    I contacted them and they are happily sending me 4 new cables from overseas. I am quite happy with their customer service. Hopefully, I won't be needing to make any cables myself but I did learn a few small things from this problem. I don't want the cables to fail again but in some way I am excited to try and diagnose the problem next time it happens.

    Thank you so much for your helpful posts. :)



--[[ ]]--