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

burnt parts

Discussion in 'General Electronics Chat' started by jonathan halder, Sep 16, 2017.

  1. jonathan halder

    jonathan halder New Member

    Joined:
    Sep 16, 2017
    Messages:
    3
    Likes:
    0
    i connected my mastech mas830l directly to the wall outlet to measure amperage thus burning.. now what should i do? 20170917_074840.jpg
     
  2. Les Jones

    Les Jones Well-Known Member

    Joined:
    May 15, 2015
    Messages:
    1,474
    Likes:
    191
    Location:
    Lancashire UK
    First get out your school science books (Probably from when you where about 13 years old) and refresh you memory about basic electricity. Then you will know that you measure the current that a device takes. NOT THE CURRENT IT TAKES TO BLOW FUSES OR TRIP CIRCUIT BRAKERS IN THE SUPPLY DISTRIBUTION SYSTEM. (Unless you have a meter capable of measuring thousands of amps.) You measure current through a wire. You measure voltage between two wires. You will then realise why you have destroyed your meter so you can buy a new one and know how to avoid destroying it.

    Les.
     
  3. JonSea

    JonSea Well-Known Member

    Joined:
    Oct 1, 2012
    Messages:
    1,198
    Likes:
    110
    Location:
    Seattle, WA
    If you haven't figured out your mistake, giving the meter a fitting burial and finding a safer hobby probably covers it.
     
    Last edited: Sep 17, 2017
  4. dave

    Dave New Member

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


     
  5. jpanhalt

    jpanhalt Well-Known Member Most Helpful Member

    Joined:
    Jun 21, 2006
    Messages:
    6,062
    Likes:
    520
    Location:
    Cleveland, OH, USA
    ONLINE

    Yes, not a good idea. Maybe you can contribute to this thread someday: http://www.electro-tech-online.com/threads/what-was-your-worst-injury-as-a-hobbyist.151918/

    Back to the present, presumably you want to try to repair the meter (MAS 830L ). Q1 is a transistor. That meter is quite popular and its schematics are on the internet. Here is one of several examples: http://airborn.com.au/circuits/mas830l.gif

    It is possible a generic transistor and the other component values are also available.
     
  6. Reloadron

    Reloadron Well-Known Member Most Helpful Member

    Joined:
    Dec 23, 2009
    Messages:
    6,801
    Likes:
    282
    Location:
    Cleveland, Ohio USA
    Consider it a lesson learned and remove and replace the meter with a new meter. The burned components are merely a symptom, the root cause should be apparent. You also may want to start with the Instruction Manual which describes how to measure DC current and note the meter was never designed to measure AC current.
    "GENERAL DESCRIPTION: The meter is a handheld 31/2 digital multimeter for measuring DC and AC voltage, DC current, Resistance, Diode, Transistor and Continuity Test with battery operated". There is no mention of an AC current measurement.
    I would write the meter off as a lesson in what not to do as visually you can only see the obvious damage done. There could be other components which are bad and not plainly visible. A new meter is available for under $12.00 USD from suppliers like Newegg.

    Ron
     
  7. jonathan halder

    jonathan halder New Member

    Joined:
    Sep 16, 2017
    Messages:
    3
    Likes:
    0
    but i want to repair it ...all others are working like i can measure wall outlet voltage,,,actually i know to measure current i need to put the leads in series with the component to check the currecnt drawn ...the thing happened is tht i connected the leads to the wall outlet to measure current
    the meter was off.... one hand i was holding thge leadson the other hand i was holding the meter ...than i turned the knob... and it somehoe landed to amperage....i am from india...everything costs much...so i cants afford to buy a new one please help!!!! 20170917_074939.jpg
     
  8. jonathan halder

    jonathan halder New Member

    Joined:
    Sep 16, 2017
    Messages:
    3
    Likes:
    0
    i
    cant make out anything in the image
     
  9. jpanhalt

    jpanhalt Well-Known Member Most Helpful Member

    Joined:
    Jun 21, 2006
    Messages:
    6,062
    Likes:
    520
    Location:
    Cleveland, OH, USA
    ONLINE
    There are several examples on the Internet. That one is quite legible on my monitor. There are other examples that may be more legible on your monitor.
     
  10. cowboybob

    cowboybob Well-Known Member Most Helpful Member

    Joined:
    Oct 22, 2011
    Messages:
    3,051
    Likes:
    479
    Location:
    James Island, SC
    You've fried the below indicated resistors:
    upload_2017-9-18_10-25-53.png
    Just before those resistors sacrificed themselves (probably Q1 also), it is extremely likely that the Vref- and IN+ inputs to the AME7106Y processor were fried as well. And no telling what else within the μC was trashed, with all that high current VAC flying around, however briefly.
     
  11. Dudley

    Dudley New Member

    Joined:
    Nov 18, 2016
    Messages:
    19
    Likes:
    1
    Location:
    Co Durham
    OK I agree with everybody else that basically the meter is probably trashed to the extent that on the internet you will probably get one cheaper than trying to repair it. The main lesson is never connect the leads of a meter to anything before selecting the correct scale to use. We have all made similar mistakes at one time or another and I'm afraid you just have to learn from it and move on. best wishes for the future
     
    • Like Like x 1

Share This Page