Android Device overheating due to Capacitors

Discussion in 'General Electronics Chat' started by appleton6509, Oct 16, 2016.

  1. appleton6509

    Thread Starter New Member

    Oct 16, 2016
    Hello Community!

    to start i work for a POS company which is trying to resolve an issue with a PC Device similar to a tablet. To start i know nothing about circuit boards and its components which is why i need help! i will try to answer any follow up questions as best as i can. Our client have over 1000 of these devices in there locations and are located in a hot topical country with high humidity. To add to that there business is HOT with lots of ovens and grills and the temperature can range for 40-50 degree F with high humidity. These PC devices seem to failing after extended use. while the manufacture claims the devices are rated for 50 F they are still failing. The manufacture is telling us that if they replace the capacitors in the device it will resolve the issue. Of course though if they replace these capacitors the client will have to shoulder the burden of paying for it and they are planning on buying hundreds more.

    i know im providing very limited information but any sort of information to point me in the right direction would be most appreciated. My question is this.....

    1) is this a possibility for resolving our problem? can a change to the capacitor resolve issues related to high temperatures?
    2) If im looking for a second opinion do i need to find an electrical engineer?

    thanks in advance!!! and sorry if i posted in the wrong section!
  2. dl324

    Distinguished Member

    Mar 30, 2015
    Welcome to AAC!

    Check your temperatures. The temps you mention are below room temperature. Did you mean degrees C?

    What makes you think failing capacitors are causing the overheating? What type are they (electrolytic, tantalum, ??)? What is the working voltage and temperature rating of the caps in question? What voltage are they operating at?

    Do the devices stop working?
  3. appleton6509

    Thread Starter New Member

    Oct 16, 2016

    1)OOPS! thats supposed to be celsius.
    2)The devices stop working completely. screens dont turn on. no lights. no power.

    i will follow up with the manufacture as they are the ones who are investigating it and simply told me "we have to replace the capacitors". i will get answers too those questions. thanks!
  4. crutschow


    Mar 14, 2008
    How much power does the device use?
    Its inside may be self-heating well above ambient temperature if it's not well ventilated.
  5. DickCappels


    Aug 21, 2008
    Things can be designed to operate up a high temperature but failure rates generally increase exponentially with temperature, even when using components rated at the operating temperature or higher. In other words, you might be seeing "normal" failures, especially if the devices are being used a lot more than the designers had intended.

    How long have these been in the field and what is the failure rate?
  6. wayneh


    Sep 9, 2010
    Personally, I would press harder for relief from the manufacturer. You purchased a product based on false claims made by the manufacturer. They should not get away with not helping you. I wouldn't pay them another cent unless they step up to support their product. Maybe a compromise on splitting the costs.
  7. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
    Not necessarily "false claims"..
    Did they state expected lifespan of 8000 hours at 50deg C,etc... and its only lasting 4000? Then that would push the ball into the manufacturers court.. assuming that 50deg C was never exceeded.. ever..
    Maybe one user has set it down next to a furnace a few times and it got to 75 deg C.... Or thousands of other variables..
    Not to mention MANY regulatory tests/certifications are nothing more than throw one device in a perfectly controlled environmental chamber and run it for 48 hours.. If its working.. Certification approved.. !!

    Sound like the margins on product standards and environments are simply too low.. aka bad purchasing decision on the clients side.. No "safety factor" at all..
    The second that local ambient hits 50.5 deg C the manufacturer is off the hook..

    If I'm buying a speed boat that needs to go 100MPH.. I'm certainly NOT buying one that is only rated to 100MPH..
  8. MrSoftware


    Oct 29, 2013
    Without more info, my guess would be that the capacitors are not causing the overheating, but the high operating temperatures are causing the capacitors to fail. Capacitors have temperature ratings, and generally the higher the temperature they operate at the shorter their service life might be. 50C is 122F, which is damn hot for a human to be working in for any length of time, and not real friendly for most electronics either. Maybe get the operating temperature inside the devices. If the internal device temperature is higher than ambient temperature, then adding a fan to circulate air through the device might help by bringing down the temperature of the electronics.

    In regards to buying more; if you measure the internal operating temperature, then compare to the temperature rating of the current capacitors and find that they are in fact operating at a higher temperature than they are rated, then that may possibly be the real explanation for the failure. And in this case, new and different (better) capacitors "might" actually resolve or at least improve the service life.
    Last edited: Oct 17, 2016
  9. wayneh


    Sep 9, 2010
    All true. We're not privy to all the details here. Quoting a temperature in the wrong units doesn't exude confidence in the poster.

    I would though ask the manufacturer to prove that their proposed fix actually works, before investing more money.
  10. bertus


    Apr 5, 2008

    What kind of capacitors are used in the system?
    There are capacitors that are rated 85°C , 125°C and even some 200°C at newark.