Easily see how hot your new iPad is getting from its log files

Discussion in 'iPad' started by TrimmTrabb, Apr 11, 2012.

  1. TrimmTrabb, Apr 11, 2012
    Last edited: Apr 11, 2012

    TrimmTrabb macrumors member

    Joined:
    Apr 10, 2012
    #1
    I thought this might be helpful to anyone who's concerned about heat with their new iPad. This isn't to rehash the long discussions about whether the iPad gets too hot or not. This is simply to help anybody who doesn't have measuring equipment and wants a better understanding of how hot their iPad gets.

    No jailbreaking or anything funky required!

    Step 1: Under Settings > General > About > Diagnostics & Usage, ensure this is set to Automatically Send.

    Step 2: On this same screen, go to Diagnostic & Usage Data. In that list, you should find a log called log-aggregated-YYYY-MM-DD.plist where the date of that file should be 2 days ago.

    Note that if you had the setting in Step 1 originally set to Don't Send, it may take until midnight for your iPad to create the log file. Look for it the next day.

    The iPad automatically creates this log file every night and sends it to Apple. It always appears to be for 2 days ago. So you'll have to wait a couple of days to see the readings for any heat you experience on your iPad today.

    Step 3: Inside the log file, you'll see temperature readings for the internal sensors of your iPad. Although you may see a few entries, I believe those are just multiple readings, but only one sensor is used on the WiFi model, and two sensors (one on the baseband) on the 4G model.

    The entry should look something like this:

    <key>com.apple.cltm.Temperature1</key>
    <array>
    <real>18.52</real>
    <real>33.009999999</real>
    <real>23.4532211</real>
    …..


    My educated guess is that for each entry like this, the 1st value is the lowest temperature recorded, the 2nd is the highest temperature recorded, and the 3rd is the average or median temperature. All measurements are in Celsius.

    Feel free to post your own readings here. In particular, if you feel your iPad is genuinely suffering from excessive heat issues, then giving the community here your temperature readings may help us give advice, or show that your iPad is normal and the perception of high heat is just subjective.
     
  2. squidkitten macrumors 6502

    squidkitten

    Joined:
    Mar 10, 2012
    Location:
    Omaha
    #2
    If your educated guess on the meaning of the readings is correct, then the hottest my iPad has gotten (as seen between all of the logs) is about 36.07ºC, so just below average human body temperature, though it typically runs much lower.

    I've never been particularly bothered by any heat from my iPad. Occasionally it does feel noticeably warmer when I have it running a strenuous app for a while, but nothing uncomfortable. Definitely no where near as hot as my MBP gets.

    On average, it's running at a nice, comfortable 73º F.
     
  3. Menel macrumors 603

    Menel

    Joined:
    Aug 4, 2011
    Location:
    ATL
    #3
    Uh oh,
    Code:
    <key>com.apple.cltm.Temperature1</key>
    		<array>
    			<real>20.559999999999999</real>
    			<real>34.509999999999998</real>
    			<real>27.543395680249336</real>
    			<real>53566.34151587636</real>
    			<integer>4491</integer>
    		</array>
    Thats like 96,000 F!
     
  4. TrimmTrabb thread starter macrumors member

    Joined:
    Apr 10, 2012
    #4
    Ha. I have no idea what the 4th and 5th values are. So ignore those. Only the first three values are clearly temperature readings.
     
  5. Batavian macrumors 6502

    Batavian

    Joined:
    Mar 10, 2011
  6. TrimmTrabb thread starter macrumors member

    Joined:
    Apr 10, 2012
    #6
    Thanks.

    I'm especially interested if anybody gets to temperatures over 45C, which is the upper limit that Apple recommends for storing the devices. However, as the temperature sensor might be on the CPU itself, it wouldn't mean that the iPad itself is "overheating". It would be interesting to hear from people who have pushed their iPads hard at 100% brightness.

    This relates to another thread I started about temperature limits for lithium polymer batteries, and whether excess iPad heat could be a concern. Unlike a laptop, the iPad battery is housed snugly against the casing, logic board, and display LEDs, and would be soaking up that heat to a greater extent.
    http://forums.macrumors.com/showthread.php?p=14699763#post14699763
     
  7. ewo1992 macrumors regular

    ewo1992

    Joined:
    Mar 11, 2012
    Location:
    Southern, CA
  8. iHeartsteve macrumors 65816

    iHeartsteve

    Joined:
    Feb 12, 2012
    #8
    Cool! I had an apple genius do this to one of their hand held devices but I didn't know you could do it yourself right on the iPad!
     
  9. Mrrikki macrumors regular

    Joined:
    Apr 7, 2010
    #9
    That's a great find, hottest mine got was 33 and I was playing EPOCH.
     
  10. nonnynz macrumors newbie

    Joined:
    May 24, 2008
  11. ZipZap macrumors 603

    Joined:
    Dec 14, 2007
    #11
    Where the hell are all the "It does not get hot" blow-hards when you need them.

    That's pretty hot. Can you still hold the iPad? Cause if you can, then you dont have a heat issue. :rolleyes:
     
  12. TroyBoy30 macrumors 68020

    TroyBoy30

    Joined:
    Jun 9, 2009
    Location:
    Atlanta GA
    #12
    so youre saying you think it really got to 96,000 degrees f? :confused:


    pretty sure what people have said is...'mine doesn't get hot', not 'none of the them get hot'
     
  13. Batavian macrumors 6502

    Batavian

    Joined:
    Mar 10, 2011
    #13
    I'm wondering if using a back cover makes a difference in heat. Were any of these results using a back cover? The aluminum back is a very effective heat sink and I'm wondering if bottling that heat is not good.
     
  14. brentsg macrumors 68040

    Joined:
    Oct 15, 2008
    #14
    That is not hot.

    32.5C is a pretty typical temperature for the fingers, so we're talking about the temperature measured by a diode that is likely embedded inside a chip, that is embedded inside a device being a MAX of 2C higher for this user.
     
  15. Menel macrumors 603

    Menel

    Joined:
    Aug 4, 2011
    Location:
    ATL
    #15
    Pretty hot, my comment about 96,000F is a joke.

    The high temp there is 34.5C, which is below normal body temperature, and very low for an IC.

    nVidia/Intel chips can safely operate as high as 100C depending on model.

    ----------

    See my post above, mine has a ZAGG LEATHERskin on the rear.
     
  16. TrimmTrabb thread starter macrumors member

    Joined:
    Apr 10, 2012
    #16
    Looks like someone on the Apple Discussion boards got up to over 46C in his log file.
    https://discussions.apple.com/thread/3810951?start=390&tstart=0
    https://discussions.apple.com/servlet/JiveServlet/showImage/2-17915468-100054/photo.PNG

    To me, that sounds like it would become a concern in certain situations. I don't have a degree in thermodynamics so feel free to correct me, but if the iPad has a case or something on the back to trap that heat, and other components like the battery start to reach over 45C, that's when gradual damage can start to occur. My guess is that user is pushing the thing to its limits as in another thread he complains that the iPad doesn't charge when plugged in and being used.
     
  17. brentsg macrumors 68040

    Joined:
    Oct 15, 2008
    #17
    Yeah, not an issue.

    One user reached what would be an uncomfortable temperature to touch, were the chip being measured accessible.

    It sounds like that individual was engaging in usage that should push temps up. Heck, I'm used to my MBP pushing 90C+.
     
  18. eq2675 macrumors regular

    Joined:
    Apr 16, 2008
  19. Fruit Cake macrumors 6502a

    Joined:
    Mar 31, 2012
    #19
    My battery gets to about 34,5celcius unde autumn weather, the iPad can get hot, but it would shutdown before it reaches critical temps. Will be interesting to see how they fare up in the north American summer in a few months time...
     
  20. eq2675 macrumors regular

    Joined:
    Apr 16, 2008
    #20
    I'm using the Incase Book Jacket and getting average temperatures of 25c

    [​IMG]
     
  21. PrayForDeath macrumors 6502

    Joined:
    Jan 3, 2012
    #21
    Very interesting tip. Thanks OP, i will turn on the diagnostics reports from now on.
     
  22. PrayForDeath macrumors 6502

    Joined:
    Jan 3, 2012
    #22
    <key>com.apple.cltm.Temperature5</key>
    <array>
    <real>26.57</real>
    <real>45.149999999999999</real>
    <real>33.526672036985232</real>
    <real>232011.81018847038</real>
    <integer>14276</integer>
    </array>


    Should I be worried? lol
     
  23. TrimmTrabb thread starter macrumors member

    Joined:
    Apr 10, 2012
    #23
    Well nobody knows for sure what the values represent, and as I said at the top, those are just my best guesses as to what the first 3 values mean.

    But let's assume they mean what I think they do: does it seem right to you that the low for that day was 26.5C (80F)? That feels a bit warm! Unless you live somewhere hot with no aircon...

    My low temperatures are between 15C and 18C, which is dead accurate in terms of the room temperature in my house. I figured that reading is from when the iPad was sleeping and not plugged in. I suppose that if your iPad is always on the charger while you're not using it, that could bump up the internal temperature higher than room temperature, even when it's in sleep mode.
     
  24. iapplelove macrumors 601

    iapplelove

    Joined:
    Nov 22, 2011
    Location:
    East Coast USA
    #24
    Here is mine..

    No idea what it means but mine hardly gets warmer than my ipad2

    key>com.apple.cltm.Temperature1</key>
    <array>
    <real>20.73</real>
    <real>36.020000000000003</real>
    <real>25.726655011654955</real>
    <real>46507.200299650125</real>
    <integer>2574</integer>
    </array>
     
  25. sekazi macrumors 6502

    Joined:
    Jan 12, 2012
    #25
    Mine shows 161,139 F

    <key>com.apple.cltm.Temperature1</key>
    <array>
    <real>18.59</real>
    <real>35.450000000000003</real>
    <real>26.439323765786426</real>
    <real>89504.631916979008</real>
    <integer>8710</integer>
    </array>
    <key>com.apple.cltm.Temperature3</key>
    <array>
    <real>17.850000000000001</real>
    <real>34.530000000000001</real>
    <real>25.081995407577384</real>
    <real>79450.194919815272</real>
    <integer>8710</integer>
    </array>
    <key>com.apple.cltm.Temperature5</key>
    <array>
    <real>19.5</real>
    <real>35.399999999999999</real>
    <real>27.06195063145805</real>
    <real>77056.149958772541</real>
    <integer>8710</integer>
     

Share This Page