1. Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.
    Dismiss Notice

12DC Sockets

Discussion in 'Automotive Electronics' started by Muttley600, Jan 16, 2012.

  1. Muttley600

    Muttley600 New Member

    Joined:
    Jan 16, 2012
    Messages:
    681
    Likes:
    5
    Location:
    Worcestershire, England
    Hi All

    Please point me in the right direction if I'm in the wrong place

    You know when you have a brainwave then hit a stumbling block well, Ive just hit the block

    If I explain what I'm trying to do, then hopefully you can tell if it will work or not.

    I have made a little box to supply power for gadgets on my motorbike, it was all going well, I know to fuse each supply, then I had this great idea of putting a LED to show if fuse blown or not (I'm trying to keep it all in a very small plastic box) then I thought wouldn't it be good if LED only light up when the jack is connected, I don't really want to put switches in as they could get knocked & the only dc sockets I can find have closed ciruits meaning the LED is on once power is in the box.

    Edit: Sockets have outgoing power with jacks on toys
    These are the sockets

    Is it possible to do what I want, do they make a open circuit dc socket, I've looked but can't find one.

    Hope someone can tell me if I'm barking up the wrong tree

    Thanks
    Graham
     
    Last edited: Jan 16, 2012
  2. cowboybob

    cowboybob Well-Known Member Most Helpful Member

    Joined:
    Oct 22, 2011
    Messages:
    3,048
    Likes:
    478
    Location:
    James Island, SC
    12VDC Sockets

    If I understand correctly, all you need to do is connect an LED with the appropriate current/voltage limiting resistive network (so as not to blow the LED with the 12VDC) across the + and - terminals of your socket. This will give you an indication that power is available, whether or not any load is applied.

    Any load you connect to the socket won't significantly change the 12VDC level such that it affects the operation of the LED.

    However, should the fuse blow due to an overload, the LED will go out.
     
  3. Muttley600

    Muttley600 New Member

    Joined:
    Jan 16, 2012
    Messages:
    681
    Likes:
    5
    Location:
    Worcestershire, England
    Thanks coyboybob, I have got that far, just wanted to make project a little more interesting:D
    So is the idea of led only lighting up when jack inserted a no then?

    does anyone make an open circuit dc socket?
    Could I remove the shunt sleeve fron the socket, has this been done by anyone?

    Thanks for any help
     
    Last edited: Jan 16, 2012
  4. dave

    Dave New Member

    Joined:
    Jan 12, 1997
    Messages:
    -
    Likes:
    0


     
  5. cowboybob

    cowboybob Well-Known Member Most Helpful Member

    Joined:
    Oct 22, 2011
    Messages:
    3,048
    Likes:
    478
    Location:
    James Island, SC

    Muttley600,

    There are all manner of sockets out there. Check Jameco.com, Digikey.com, etc. You've got the right idea about using a switched closure for positive (or negative, for that matter) DC source. Anything that gives you a closure when a plug is inserted to complete the circuit to the LED.

    There would also be a way to achieve this with the Jack you referenced (which breaks when a plug is inserted), with a simple transistor switch. It would draw current when not in use, but it could be designed to draw extremely little when off.

    With no plug in the jack, the "sleeve shunt" contacts are closed and grounded. This could be used to ground the base of a transistor and keep it in a non-conducting state. Insert a jack, thereby opening the shunt to ground and the transistor would then conduct, thereby powering the LED.

    It's late. I can get you an example schematic tomorrow, if you like.
     
  6. Muttley600

    Muttley600 New Member

    Joined:
    Jan 16, 2012
    Messages:
    681
    Likes:
    5
    Location:
    Worcestershire, England
    Wow, that sounds ideal, I'll look forward to your post:D
    Thanks a miliion

    Edit: wow your -5 hours on me, have you been up all night?
     
    Last edited: Jan 17, 2012
  7. cowboybob

    cowboybob Well-Known Member Most Helpful Member

    Joined:
    Oct 22, 2011
    Messages:
    3,048
    Likes:
    478
    Location:
    James Island, SC
    Left image is ON condition, right is OFF.

    You can play with R3 (collector side) to increase or decrease forward voltage and current on the LED. This will, of course, vary the total current in the system.

    Note that, as depicted, the OFF (quiescent state) current is 1.2 mA (with 90mV across the LED) and 3.089 mA (with 1.45V across the LED) when ON.

    A 1 mA OFF condition "leakage" is not a significant drain on your battery.

    Jack Shunt Switch is the switch inside the Jack you have selected that is NC (Normally Closed) and opened when a plug is inserted.

    Obviously, the ammeter is not needed for the circuit. Just connect the Battery B+ to the juncture of R1 and R3. Also, the "VF1" symbol is not a needed part of the circuit. It's an output tap that displays the voltage across the LED (in the simulation) that I forgot to remove.

    I did not include an image of the fuse(s) already in the battery circuit.

    Hope this suits your needs.

    View attachment 60248 View attachment 60247
     
    Last edited: Jan 17, 2012
  8. Muttley600

    Muttley600 New Member

    Joined:
    Jan 16, 2012
    Messages:
    681
    Likes:
    5
    Location:
    Worcestershire, England
    will get back in morning with Q's, Getting grief for being on here late.eek! lol
    Thanks
     
  9. Muttley600

    Muttley600 New Member

    Joined:
    Jan 16, 2012
    Messages:
    681
    Likes:
    5
    Location:
    Worcestershire, England
    Ok this should be fun, as a complete newbie to electronics this is the start of my learning.
    I have looked up 2N2222 & that makes sense, so this would be purely for lighting led & not have main power going through it?
    I take it R3 etc are resistors with varying outputs & I would need tovary these according to the load being drawn.
    Have I understood that right?
    Thanks
    Graham
     
  10. Diver300

    Diver300 Well-Known Member

    Joined:
    Oct 19, 2007
    Messages:
    3,089
    Likes:
    102
    Location:
    England
    Why not just put an LED (with appropriate limiting resistor) in parallel with each fuse? Then the LED will light if the fuse is blown and there is a load.

    On mains circuits, fuses are protection against electric shock, and any indicator like that could be dangerous. On a 12 V system, there is no need for protection agains shock, only overcurrent, and the LED will work fine.

    You should probably put a high value resistor, maybe 10k or so, in parallel with the LED. Otherwise you might get the LED glow with stupidly small leakage currents. With a 10k resistor, you need at least 0.2 mA to flow before the LED will light.
     
  11. cowboybob

    cowboybob Well-Known Member Most Helpful Member

    Joined:
    Oct 22, 2011
    Messages:
    3,048
    Likes:
    478
    Location:
    James Island, SC
    We just lost power, so I'm writing this by candle light. What an interesting juxtaposition.

    OK, by the term "main power", I'm assuming you mean the Bike's 12VDC battery.

    Think of this circuit, in all its parts, as simply an on/off switch, not unlike a light switch in your house: connected to the mains, it either interrupts, or passes power from the mains to the light (or, in this case, from the battery to the LED). A good example would be a flashlight, or torch, I think you all call it.

    So, to answer your first question, the circuit IS connected to the battery.

    As to the resistors, they don't really have an output as such. They AFFECT the parameters (working characteristics) of a circuit. In this case, there's no need to alter the values at all. Build the circuit as specified. I only suggested varying R3 since doing so would vary the intensity of the output of the LED.

    Your last thought concerning a varying load: again, this is an on/off switch circuit: it does not control any load, other than the LED. Were the plug not connected to anything, merely putting the plug in the jack will cause the LED to turn ON. Removing the plug will cause the LED to turn OFF.

    For some useful info on electrical/electronic theory, try the Theory button at the top of this page.

    Power's back up. Now I can post this.
     
    Last edited: Jan 18, 2012
  12. Muttley600

    Muttley600 New Member

    Joined:
    Jan 16, 2012
    Messages:
    681
    Likes:
    5
    Location:
    Worcestershire, England
    Because the load will be there as soon as bike is turned on, if that makes sense

    Is there a link anywhere so I can get a better understanding of what resistors are, do etc, I'm starting with very little knowledge here :eek:
    I know a 470r will work with led, but after that I'm lost :D

    sounds like you were having fun :D

    yes, bike battery

    cool, got that


    yep :D


    so resistors can be used for a lot more things than leds, they can alter V's as well if i were to .....
    hold that thought, lets do the one box to start with :D
    I'm trying to start on something easy that I can then move onto something more complicated to help my understanding of how & why things do what they do


    sounds ideal for this bit of project


    Thanks

    I have limited time this week as I'm rushing at work as I'm off next week, so hopefully I can learn lots more next week :D

    Heres a basic diagram of what I wanted to start with, hopefully, you can see by my diagram that I need to get my head around the way people put things onto paper & what it actually means.
    but if I don't start somewhere I'll never learn anything

    [​IMG]

    Thanks for all your help with this both [​IMG]
     
  13. 4pyros

    4pyros Well-Known Member Most Helpful Member

    Joined:
    Oct 22, 2010
    Messages:
    4,368
    Likes:
    282
    Location:
    Pennsylvania, USA
    Having a LED on when nothing is pluged in is easy, no additional parts.
    Having the LED on only when somthing is pluged in is alot harder and needs more parts.
    Is it worth over complicating the power box for something "its nice to have"?
     
  14. cowboybob

    cowboybob Well-Known Member Most Helpful Member

    Joined:
    Oct 22, 2011
    Messages:
    3,048
    Likes:
    478
    Location:
    James Island, SC
    I've taken the liberty to re-draw your schematic below, as I understand it.

    There are some component issues that need to be addressed, but for the time being I'm asking that you peruse the schematic and see if it is a fair representation of you thoughts.

    Note that LED2 is always on when Accessory power is applied to the "Power Box". LED1 is on anytime ANY jack has a plug in it. If each Jack has to have its own LED, then 3 more LED switches (like the one already shown) will be needed.

    Let me know what you think.
     
    Last edited: Jan 19, 2012
  15. Muttley600

    Muttley600 New Member

    Joined:
    Jan 16, 2012
    Messages:
    681
    Likes:
    5
    Location:
    Worcestershire, England
    I see what your saying but If I explain my toys work already, hopefully you will see that this is not just about getting something to work but to actually *read hopefully* understand what componants do what & why, so I can learn about electronics but still holding an end goal so I can see something & relate it to my understanding :) I could read what componants do all day long but I wouldn't remember it by tomorrow, if I actually relate it to something, it will stay with me for life & in the process be able to use what I've made :)
    Hopefully this is a nice easy starting project & gradually increasing difficulty with each one.
    I hope to build a rear mounted box that cleans power etc, repair an old radio for the fun of it, the list could go on & on along with many numpty Q's along the way [​IMG] but hopefully that way I'll remeber what I learn

    Wow, what can I say, fantastic, you must have a nice bit of software to be able to create that [​IMG]

    ok, now I'm starting to enjoy this, it has taken me ten minutes to get my head around which are earth & live wires *don't give up on me yet [​IMG]*

    I take it F1,2 etc are fuses but I can see only three, if you look between numbers 9/10/3
    then 7/6 there are 8 + that depict fuses in my world [​IMG] one to each jack

    Can I have a go at drawing *sorry, I don't have nice software* it tomorrow & get your advice on my understanding of it. Then I can look a bit more at what resistors do & why & see if I have understood what a transistor does, then you can correct me if needed [​IMG]

    Thanks for all your help, I really appreicate the time you have put in [​IMG]

    Best regards
    Graham
     
  16. JMW

    JMW Member

    Joined:
    Nov 21, 2011
    Messages:
    92
    Likes:
    1
    Location:
    Puerto Rico
    Go with Diver 300. You don't need useless lights, you will know when it is working but need to know when it fails. As for fusing, remember, in general you are protecting the wire, the device will normally clear to protect the fuse. And unlike the idiots on that TV bike show, please use grommets or armored cable.
     
  17. 4pyros

    4pyros Well-Known Member Most Helpful Member

    Joined:
    Oct 22, 2010
    Messages:
    4,368
    Likes:
    282
    Location:
    Pennsylvania, USA
    Ok sounds like fun.
    As always the skys the limit, knowing when to stop will come from experience.
     
  18. 4pyros

    4pyros Well-Known Member Most Helpful Member

    Joined:
    Oct 22, 2010
    Messages:
    4,368
    Likes:
    282
    Location:
    Pennsylvania, USA
    As for the fuses;
    The main fuse should be at the power source, IE battery to protect the wire run to the load.
    The 5 volt regulator should have a fuse on the input to protect the regulator.
    The outputs have to be fused.
    If you put a LED with a dropping resister across a fuse it will light if the fuse blows.
    If you put two diodes in series with each connector power supply. They will light a LED if a load is present, IE something plugged in.
    this can all be done with diodes and maybe better suited for a beginner.
    Let me know if you would like more info on the diode approach.
    Andy
     
  19. cowboybob

    cowboybob Well-Known Member Most Helpful Member

    Joined:
    Oct 22, 2011
    Messages:
    3,048
    Likes:
    478
    Location:
    James Island, SC
    Works for me.

    Once you done the hand drawing (schematic) of one jack wired and configured it the way you like it, all you've got to do is "clone" it and it's components/wires (with the appropriate power) as many times as you like. Give yourself lots of room to draw the thing. Hopefully, you can see some of the standard symbols for various components normally used. All part of the learning curve.

    Fusing everything is the same thing. I didn't fuse things as I ordinarily would because, especially, the voltage regulation (and the associated current requirements) issue is yet to be determined.

    And yeah, I like simulator I have. It's pretty versatile (TINA Basic, ver. 9).

    I applaud your goals. As you will see, not all that difficult once it starts to click.

    This can be an incredible fun.
     
    Last edited: Jan 19, 2012
  20. KeepItSimpleStupid

    KeepItSimpleStupid Well-Known Member Most Helpful Member

    Joined:
    Oct 30, 2010
    Messages:
    9,963
    Likes:
    1,099
    ONLINE
    I'm going to come in here from left field without actually reading everything in this thread.

    I'd like you to look here: http://www.motorcaravanning.co.uk/shopuk/procar_adaptors.htm

    Those Procar lighter plugs are the BEST I have ever seen. They work and I'm in the US. Most of the JUNK I've seen in the US just randomly looses connection. They do have an internal European fuse that is a little strange looking.

    Note that when you remove the red collar, they become a DIN automotive LOCKING power connector. This is what I would reccomend.

    For the fuse blown indicator, I would consider the LED/Resistor combination across the fuse although I would probably make this only work at "Lamp Test" part of the ignition circuit. This part of the "LAMP TEST" would indicate a failure instead. You would also have a separate push button to check for a fuse failure as well.

    Just a suggestion.

    You can buy the coaxial power jacks/plugs like yours that can be locked in place too. Minuteman Electronics has them.
     
    Last edited: Jan 19, 2012
  21. 4pyros

    4pyros Well-Known Member Most Helpful Member

    Joined:
    Oct 22, 2010
    Messages:
    4,368
    Likes:
    282
    Location:
    Pennsylvania, USA
    Opps Repeat
     
    Last edited: Jan 19, 2012

Share This Page