Page 2 of 2 FirstFirst 12
Results 11 to 15 of 15

Thread: Newbie with a problem ?

  1. #11
    Newbie
    Join Date
    Nov 2009
    Posts
    7
    Hi moysie....

    I've been looking at these .....

    http://www.maplin.co.uk/Module.aspx?...6&U=shop_N98AP....


    and....wats this polarity thing ?

    cheers

  2. #12
    Newbie Moysie's Avatar
    Join Date
    Oct 2007
    Location
    Fife, Scotland
    Posts
    46
    Blog Entries
    1
    Quote Originally Posted by 784cy View Post
    Hi moysie....

    I've been looking at these .....

    http://www.maplin.co.uk/Module.aspx?...6&U=shop_N98AP....


    and....wats this polarity thing ?

    cheers
    Hi Tracy,

    The Polarity is which way the Positive and negative are, if you reverse the connections there is a very good chance that you will cause damage to the device that will be connected to the lead.

    To find out which wire is pos and neg, if you get hold of a multimeter/ Voltmeter (Maplins sell cheap ones around 5 like this )
    Wth the multimeter set on "voltage DC", put the red probe onto one wire and the black probe onto the other wire and read the voltage.
    If the multimeter shows negative voltage then the black probe is on the Positive and the Red probe on the Negative wire. If multimeter shows positive voltage Then red= positive, Black = negative.

    TIP: Label each wire so that you know what is pos and neg, otherwise you may get muddled up and end up getting the wrong wire.

    To double check that you got the wire identification correct you can take the multimeter again on "volts DC" and put the red probe to one wire and theblack wire to a earth/ground point on the car (such as ignition barrel, one of the bolts under the dash etc). One of the wires will read voltage to ground (this is the positive), and one won't read voltage to ground (this is the negative).

    These types of conectors can be handy, im sure the two pins are different sizes so can only be insterted into the holder one way. One problem with this type of connection is that is is TOO EASY to change the connector. Yes i know that sounds stupid, but if you can easily change the connector to suit what ever device you want to power, plug it in and BANG!!! (Exageration) You overlooked the voltage side of things, you just plugged in a 6V device onto a 12V supply and fried the internals.

    If you have any other questions let me know.

    Regards Michael

  3. #13
    Newbie
    Join Date
    Nov 2009
    Posts
    7
    Right....I understand now....

    My neighbour has the gadgets to do the Voltage check, just got to catch him....

    If say I wanted to power portable dvd player or Tv 12v and it's got enough volts coming through the cable, is there a standard DC plug size for such items ?

    Or.....should I remove the power cable end from the DVD player and put it onto the one in the car ?


    I've also looked at these

    http://www.maplin.co.uk/Module.aspx?ModuleNo=43094

    In the hope that I can convert the exsisting plug into something smaller.....


    You can probably work out that I want to do this as simple as possible...and I'm not expert, so any information would be greatly rec'd


    Tracy

  4. #14
    Newbie Moysie's Avatar
    Join Date
    Oct 2007
    Location
    Fife, Scotland
    Posts
    46
    Blog Entries
    1
    Quote Originally Posted by 784cy View Post
    Right....I understand now....

    My neighbour has the gadgets to do the Voltage check, just got to catch him....

    If say I wanted to power portable dvd player or Tv 12v and it's got enough volts coming through the cable, is there a standard DC plug size for such items ?

    Or.....should I remove the power cable end from the DVD player and put it onto the one in the car ?


    I've also looked at these

    http://www.maplin.co.uk/Module.aspx?ModuleNo=43094

    In the hope that I can convert the exsisting plug into something smaller.....


    You can probably work out that I want to do this as simple as possible...and I'm not expert, so any information would be greatly rec'd


    Tracy

    Tracy,

    I believe that the DC plugs are not really standardised for certain voltages/ currents etc, refer here.

    In order to decide the best approach, you would have to decide/check several factors:

    1. What devices are you going to use. I.e. Only DVD or additional devices as well?
    2. What is the required input voltage for these devices?
    3. Do all of the devices use the same size of plug?

    once the above decisions and checks are done then it would be easier to decide wherer to:

    1. Use the lead supplied with DVD player.

    2. Use a universal incar laptop power supply like this. This device allows you to alter the supply voltage to the devices and has the interchangable plug to suit which device you want to use. If you wanted you could cut off the cigarette lighter plug and join the cable to your cable in the car.
    Remember what i said earlier about the interchangable plugs and the voltage, as long as you alter the voltage before plugging in your device you;ll be fine.

    3. Convert the cable to have a cigarette lighter socket on it. Most portable devices now come with incar cables/supplies.

    Let me know how you get on or if you require further assistance.

    Regards michael

  5. #15
    Newbie
    Join Date
    Nov 2009
    Posts
    7
    Interesting....I didnt think about put the cig lighter socket back on it....

    mmm....1 and 2 are going to be my best options...

    The portable dvd player I have got does not fit the cable, hence why I'm doing all this......

    I was going to get a better player when I've sorted the cable problem out, what I didnt want to do was go and get a new once and it not fit the socket....

Page 2 of 2 FirstFirst 12

Similar Threads

  1. Newbie with a problem
    By TreColl in forum Newbie
    Replies: 5
    Last Post: 08-11-2008, 09:58 AM
  2. Newbie problem with aux and external dvd player
    By wirelessdude04 in forum Car Audio
    Replies: 5
    Last Post: 06-07-2008, 05:49 PM
  3. DSATX problem, not power switch problem!
    By VThokieME in forum Power Supplies
    Replies: 4
    Last Post: 05-04-2008, 12:22 AM
  4. The craziest USB soundcard problem ever
    By Sibi in forum General Hardware Discussion
    Replies: 6
    Last Post: 03-07-2008, 09:25 AM
  5. Newbie DC/DC PSU problem
    By masch in forum Power Supplies
    Replies: 2
    Last Post: 06-30-2002, 07:43 AM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •