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12DC Sockets

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

  1. Muttley600

    Muttley600 New Member

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    Well that link I provided was useless, it saves them to a mobile version, so there was me thinking I could help while I was at work & it was no use at all as it was too small to see [​IMG]

    More interestingly, when I just edited the original post, there was an static electro tech message instead of photobucket image message, so it looks like this site is killing my photos [​IMG] am I not meant to be psoting photos or does some computer think they are spam [​IMG]

    anyways, glad theres nothing wrong with photobucket account & you figured it out CBB [​IMG]

    I'm just going to grab a cuppa an smoke then try & get these questions asked as I will be out all day tomorrow & won't get chance to get on here until the evening
     
    Last edited: Feb 15, 2012
  2. Muttley600

    Muttley600 New Member

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    What were you looking at then [​IMG]

    In case that happens again, put this link somere safe so we can still discuss if I cant sort it out straight away, I've made a new album & photos/screensnips will appear as I add them

    http://s1201.photobucket.com/albums/bb348/Mutley41/Electric training/

    Even that's no good, they are still too small for me to see properly

    I've put snips back in post #533 so you can see what my query was regarding measuring, but for the main questions I'll post them in new post

    ok, forget today, I'm going to try & find out what the problem is, they have been taken off again, we aren't going to get very far without pictures

    I said earlier it was going to be one of those days, I'm off to sulk.................
     
    Last edited: Feb 15, 2012
  3. KeepItSimpleStupid

    KeepItSimpleStupid Well-Known Member Most Helpful Member

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    Links with words can be made like this:

    [url=http://the link/]The text you want[/url]

    Pictures can be added using "Go advanced". You don't have control of them when you use this option. i.e you cannot remove them, I think. You MAY, not sure, but you may be able to remove pics if you use the album function of the forum. If you want to use text, like above, you will have to put the image into an album. Some VB forums allow access to pics posted.
     
    Last edited by a moderator: Sep 14, 2013
  4. dave

    Dave New Member

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  5. KeepItSimpleStupid

    KeepItSimpleStupid Well-Known Member Most Helpful Member

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    He has an iPhone which is the WORST one to deal with. SO you ABSOLUTELY need a USB charging port. That little box does something special for the iPhone.

    You might have to build a way to check that stuff is working too. By that, I mean a way to measure the current drawn by the USB wire. This might require creating a breakout box to look at the current flowing in the 5V line.
    Or you can assume it's going to work.

    You could create a crowbar for the 12 V devices, just in case the electrical system on the bike malfunctioned.

    You could also generate 12 V regulated power for those devices that are 12 V.

    ====

    Remember when the bike was 12 V DC. In a way it's not. When the bike is off, the battery can be represented by an ideal voltage source, a series resistor and a parallel resistor at constant temperature. The battery discharges slightly just sitting.

    When the bike is running, it's an entirely different story. The voltag will rise to about 13.8 Volts

    There is a DC component, but there is also an AC component to the mix. The AC component will look like the following:
    Take a sine wave and flip the negative portion. Now, put it on top of the DC. The height will be small, but it's there. This is called "ripple". The frequency will change with regulation and the amplitude will change with load. If you remove a two diodes from the alternator, every third peak will be missing.
     
    Last edited: Feb 15, 2012
  6. Muttley600

    Muttley600 New Member

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    Keep that thought KISS, making more boxes sounds like fun but I gotta learn AC with your & CBB's help first, otherwise like just I'm not really understanding, I need to be able to put pics up so we can all see what we are actually talking about.

    Back tomorrow evening & hopefully find out whats going on by then

    Night both
     
  7. cowboybob

    cowboybob Well-Known Member Most Helpful Member

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    KISS,

    That's a new term to me. What's a "crowbar" in this context?

    CBB

    OK. I googled it. I see. Most of the schematics looked like they'd, basically, short to ground.

    Do they "latch" for the duration of the over voltage? I assume they would, thus blowing the fuse. Course, that's better than smokin' the toy.
     
    Last edited: Feb 15, 2012
  8. KeepItSimpleStupid

    KeepItSimpleStupid Well-Known Member Most Helpful Member

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    Yep. Basically this: http://www.radio-electronics.com/info/circuits/scr_overvoltage_crowbar/scr_over_voltage_crowbar.php However that overvoltage automotive thing that Graham found might make it obsolete. Remember that the regulator could fail in the bike probably creating an 18V rail although most of the alternator failures I've experiences were undercharging or shorted diodes, one firewall connector and th one with no warning. The solder joint on the rotor broke and the car stopped without warning.
     
  9. cowboybob

    cowboybob Well-Known Member Most Helpful Member

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    KISS,

    Good info.

    If we're gonna do this, may as well do it right. Always best to assume and prepare for the worst.

    After many years of being involved in off-shore work, I made it an iron clad policy that I did not go to sea on a boat with only one engine.
     
  10. KeepItSimpleStupid

    KeepItSimpleStupid Well-Known Member Most Helpful Member

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    The LT4356 surge stopper looks essential.
    Not sure about the crowbar at this point.
    The USB Power port seems essential. The question is "How do you know it works?"
    A 12 V to 5V power supply seems essential. I don't think it makes sense to make from scratch, but the TI low component count part might be OK, but not sure of the current rating and I don't think you can synchronize the oscillators.

    For the 12V ports, we could opt for current limiting and/or fuse protection

    Then there is the real estate agent. How much room is there? Kinda need to be looking at the case options too. We could be close.

    Not sure if any of this needs to run unless the cycle is stopped because that "could" add another can of worms. e.g. a Bluetooth headset charger

    the program USBDeVIEW, I think will show the power of devices. I'm not sure if the device manager will, but I think it does.
     
  11. cowboybob

    cowboybob Well-Known Member Most Helpful Member

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    Looks like a plan.

    And I think it's obvious that Graham would like to build himself, as much a possible, the gear.

    I know I would, just for the thrill of having done it and be able to say so.
     
  12. Muttley600

    Muttley600 New Member

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    Have been busy today but means I get to finish early, should be able to get on here properly about 17:00hrs, now 14:00. Looks like you guys have been busy, tried to log in on last smoke break but couldn't, just went to try again & already logged in, I swear I'll never understand these phones.lol
     
  13. cowboybob

    cowboybob Well-Known Member Most Helpful Member

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    Hey, Graham.

    On-line...
     
  14. Muttley600

    Muttley600 New Member

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    Hiya CBB, giveme 5 to get cuppa & then I'll ask those questions, nice finishing work early [​IMG]
     
  15. cowboybob

    cowboybob Well-Known Member Most Helpful Member

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    Okey dokey. (Was that fast or what??)
     
    Last edited: Feb 16, 2012
  16. Muttley600

    Muttley600 New Member

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    First off, sorry for being a grump yesterday, I had a stinking headache & not being able to see photos was the straw that broke the camels back, sorry.

    Then there are posts we need to return to afterwards: #529/#544/#544-550

    For the sim, first question was about how your measuring the 0.33 volts in post #533

    I'm not understanding where your getting your 1.414v measurement from???? I've got the right reading on the multimeter but would like to know the process

    Why is the DC signal moving up the scope? or is that normal for all DC signals

    Why do we have different waves: In properties of voltage generator, then under waves, there are all diffrent styles, how do you know which wave to choose, there are about six?
    For the life of me I can't find them now but there was another bit that had names like hammerhead etc, are they waves as well

    What is the phase bit for?

    What are the differences between:
    Linear
    Linear -db - I take it this one is for sound
    Logarithmic
     
    Last edited: Feb 16, 2012
  17. KeepItSimpleStupid

    KeepItSimpleStupid Well-Known Member Most Helpful Member

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    Graham:

    What kind of electronics test equipment to you own? Multimeter? Power supply? Soldering stuff?

    CBB:
    Do you think it's reasonable for graham to acquire some USB breakout boards? These are boards that make the USB connector to a terminal strip? and

    Acquire a Hall effect current sensor such as this one: http://search.digikey.com/us/en/products/ACS714ELCTR-05B-T/620-1258-6-ND/1955914 and of course the USB power port IC and a sacrificial USB something even if it's an external battery charger?

    The idea would be to breadboard a current sensor for USB, so that it's possible to figure out what the system is supplying to the device. Then breadboard a USB power port and see if it works correctly.

    In the process, use something sacrificial, so you don;t have to risk an iPhone while debugging. Once the test jig becomes boxed, then test with the real thing. Think of something cheap that can be used sacrificially. All it would take is an unintentional polarity inversion on the power and poof.

    Just thinking out loud.
     
  18. Muttley600

    Muttley600 New Member

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    I have a breadboard/multimeter, soldering stuff (guess that will show if If I can use my 1.2mm solder or need 0.7mm) Power supply

    Have a look here & give me a clue

    I could buy a couple of these thet are cheap & we will know load
     
    Last edited: Feb 16, 2012
  19. cowboybob

    cowboybob Well-Known Member Most Helpful Member

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    That's the RMS (Root mean square) value of the AC signal, or 0.707 X Peak to Peak value of of a Sine Wave (which is, in this case, 2 VAC, or 1.414V).

    Anytime you measure an AC voltage with a voltmeter (as apposed to observing it on a scope) the voltmeter displays the "so-called" RMS value. It's a trigonometric function needed to get the "real" value. Don't ask.

    Moving up how? If it's a true DC signal, at the very first it will cause the trace to "move" to the level of its value (1VDC, 12 VDC, etc) but then remain at that level. It should not move.

    ALL the names fairly well describe their shape, i.e., Sine, Square, Sawtooth, Pulse, etc. They all have different attributes (and there are a BUNCH) that are useful in electronics. We can cover them later as they become important.

    I'm going to go back and look at the posts you mention.

    Also, if you can, when you "sniip" a schematic shot, can you make sure the schematic is fully shown (i.e., not under an instrument)? Reason I ask is so I can see how that circuit is set up for that particular test. Thanks.

    And KISS, Yes, a USB BOB is a good idea. I might get one myself.

    CBB
     
  20. cowboybob

    cowboybob Well-Known Member Most Helpful Member

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    KISS,

    The ACS714 sure is sweet. That could be placed (with a few other components) way upstream and protect the whole shebang.

    The surface mounting isn't so attractive, but hey...

    Never thought about the Hall effect being used for anything other than a switch. Pretty (actually, very) clever.
     
    Last edited: Feb 16, 2012
  21. Muttley600

    Muttley600 New Member

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    I don't know why but sitting here trying to work it out, going to have to come back to in a min

    I'm looking for this 333.3mVDC reading & I can't find it anywhere
    [​IMG]

    Why can I get the 471.4mV but not the 333.3mVDC [​IMG]

    Moving up the scope but that makes sense [​IMG]
    so whats all this about DC on AC bias [​IMG]

    Fairy nuff


    ok
     
    Last edited: Feb 16, 2012

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