How To Use This Meter?

Discussion in 'The Projects Forum' started by Pjam, Apr 25, 2016.

  1. Pjam

    Thread Starter New Member

    Apr 25, 2016
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    First I should say Hi to everyone here and also warn you, I don't have a clue what I doing, I'm probably dangerous to myself and others! heheh
    But, I'd love to use this somehow. Ideally in a box / domestic bulb / dimmer arrangement.
    It was designed many years ago in a very non-domestic situation. It was in a UK railway switch room (600V I think!)
    Anyway, how can I use it in a way that'll make that needle swing? Is there any practical way? It is a beauty I think.

    Ammeter brighter.jpg
     
  2. Dodgydave

    AAC Fanatic!

    Jun 22, 2012
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    Its an AC ammeter, you will need to remove the shunt wire and diodes inside, and you can use it as a simple voltmeter or other range ammeter by altering the shunt resistance.
     
    Last edited: Apr 25, 2016
  3. Pjam

    Thread Starter New Member

    Apr 25, 2016
    8
    2
    Ah !

    Shunt wire Dave? Can you tell me any more? what am I looking for? Imagine you talking to a 5 year old hahah

    Maybe I should get a photo of the guts :confused:
     
  4. Dodgydave

    AAC Fanatic!

    Jun 22, 2012
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    Pictures would help....
     
  5. Pjam

    Thread Starter New Member

    Apr 25, 2016
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    Ok more photo's tomorrow. Thanks for your help Dave :)
     
  6. KL7AJ

    AAC Fanatic!

    Nov 4, 2008
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    I believe that might be a thermocouple ammeter...if so you do NOT want to modify it....it's far too valuable in its native state. If you have an HF transmitter and a dummy load, you can see if it reads with RF excitation.
     
    Pjam likes this.
  7. Pjam

    Thread Starter New Member

    Apr 25, 2016
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    Can you tell from this Detail 1a.jpg photo? Tis a lovely old thing. Must say I'm reluctant to mess with it ..... but then I'd love to have it working and on display.
     
  8. Picbuster

    Member

    Dec 2, 2013
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    Help!!!! stop!!!!!! antique do not modify keep as is. should be in a museum.
    The coil will, when current flow, move the L shape part connected to the arm.
    Size of coil number of windings will define reading.
    Please promise the whole world that you keep this as is.
     
  9. MrChips

    Moderator

    Oct 2, 2009
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    That is a moving iron ammeter that measures RMS DC or AC.
    You don't see too many of those.
    I would suggest you donate it to a school that teaches physics.
    You should also document it by taking lots of photographs.
     
  10. Pjam

    Thread Starter New Member

    Apr 25, 2016
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    :) Hahhah. OK I promise. Just to really show off I have a pair of these!

    Must say, even without knowing much about the thing, it is impressive ....... does it have any sale value?
     
    ErnieM likes this.
  11. KL7AJ

    AAC Fanatic!

    Nov 4, 2008
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    Yes...it is a direct RMS ammeter. It is a gem. Do not modify...do not pass Go....do not collect $200.
     
    Sinus23 likes this.
  12. Pjam

    Thread Starter New Member

    Apr 25, 2016
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    Thanks to everyone for the good advice.
    I did a little research, EEC was right there at the beginning of electrification of trams and railway! Amazing.

    [​IMG]
     
    RichardO likes this.
  13. MrChips

    Moderator

    Oct 2, 2009
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  14. profbuxton

    Member

    Feb 21, 2014
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    It looks like a moving iron meter driven via a 5A current transformer. feeding it with 5A ac should get it moving.
     
  15. Pjam

    Thread Starter New Member

    Apr 25, 2016
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    Thanks Prof. If you think this might work then I should take a closer look ......... hmmmmm a 5A current transformer. What kinda thing did you have in mind?
     
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