Amps are big.

Discussion in 'Off-Topic Members Lounge' started by flippineck, Oct 29, 2016.

  1. flippineck

    flippineck

    Joined:
    Sep 8, 2013
    Messages:
    235
    Likes Received:
    8
    Location:
    North of England
    Having spent an evening soldering 12 off, 20W 12V halogen lightbulbs together to create a 'dummy load' to simulate something behind a battery charger eating up the energy supplied by solar panels, I was quite suprised.

    Rigged them up as six strings of two each series string, all connected in parrallel.

    I expected that applying 24V from my new bench PSU, might result in a few amps flowing and an array of moderately lit bulbs.

    As it was, the bulbs started lighting up at a pretty low volts level and by the time I'd cranked it up to 24V, I had nearly 10A flowing and the fixture I'd rigged up to hold the lamps was starting to go on fire.

    The PSU's rated to happily supply 10A but I was starting to feel like I was in welding territory!

    There's a lot more punch in an amp than I thought.
     
    flippineck, Oct 29, 2016
    #1
    1. Advertisements

  2. flippineck

    (*steve*) ¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd Moderator

    Joined:
    Jan 21, 2010
    Messages:
    22,690
    Likes Received:
    1,928
    Location:
    Mid way between Beijing and the Ronne Ice Shelf
    Well... Each bulb requires 20/12A = 5/3A = 1 2/3A, so each string will be 1.667A times 6 strings, that's 10A.
     
    (*steve*), Oct 30, 2016
    #2
    1. Advertisements

  3. flippineck

    flippineck

    Joined:
    Sep 8, 2013
    Messages:
    235
    Likes Received:
    8
    Location:
    North of England
    Yes the maths should have been obvious to me I guess.. If there's 10A on offer then the bulbs will take it! Just pleased that my PSU survived the ordeal. Pity I've already left averagely good ebay feedback!

    Next time I won't use a plywood frame-thing to hold the bulbs. What was I thinking..

    This is the PSU in case anyone needs a recommendation for a really easy to use, rugged bench supply that seems capable of surviving abuse .. not the seller I used but same type

    www.ebay.co.uk/itm/142045067116
     
    flippineck, Oct 30, 2016
    #3
    1. Advertisements

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Similar Threads
  1. Jerome Jahnke

    12 Volts 3 Amps DC vs 12 Volts 6 Amps DC

    Jerome Jahnke, Sep 27, 2004, in forum: Electronic Basics
    Replies:
    1
    Views:
    1,160
    The little lost angel
    Sep 27, 2004
  2. support2
    Replies:
    2
    Views:
    495
    Robert_fay
    Jun 15, 2017
  3. Nuse

    Intel Edison Developer Challenge - Are you applying?

    Nuse, Jul 13, 2016, in forum: Microcontrollers and Programming
    Replies:
    0
    Views:
    261
  4. Bri Choj
    Replies:
    4
    Views:
    383
    Sunnysky
    Jul 29, 2016
  5. shax11

    Are Circuit Boards necessary?

    shax11, Jul 28, 2016, in forum: Electronic Projects
    Replies:
    5
    Views:
    596
    HippyNerd
    Aug 3, 2016
  6. Lawrenciumbc

    Are optical power and electrical power directly comparable?

    Lawrenciumbc, Jul 28, 2016, in forum: Electronic Projects
    Replies:
    4
    Views:
    292
    Lawrenciumbc
    Jul 30, 2016
  7. khobby

    What are these connectors called?

    khobby, Sep 18, 2016, in forum: General Electronics Chat
    Replies:
    2
    Views:
    250
    grumps
    Sep 19, 2016
  8. blackcats

    Transistor for supplying ground, I think mine are way overkill

    blackcats, Oct 14, 2016, in forum: General Electronics Chat
    Replies:
    3
    Views:
    252
    AnalogKid
    Oct 14, 2016
Loading...