Somewhat related to the "diagnosing disappearing devices" thread, I have 
also noted that sometimes my temperature readings go crazy.  Example 
from a temperature log:

2013-11-05 04:31:10 ,Basement Fridge Thermometer,       7.125
2013-11-05 04:32:10 ,Basement Fridge Thermometer,      7.0625
2013-11-05 04:35:10 ,Basement Fridge Thermometer,          45
2013-11-05 04:36:10 ,Basement Fridge Thermometer,        40.5
2013-11-05 04:37:10 ,Basement Fridge Thermometer,     43.4375
2013-11-05 04:38:10 ,Basement Fridge Thermometer,      43.375
2013-11-05 04:39:10 ,Basement Fridge Thermometer,     45.3125
2013-11-05 04:40:11 ,Basement Fridge Thermometer,      45.875
2013-11-05 04:41:10 ,Basement Fridge Thermometer,          85
2013-11-05 04:42:10 ,Basement Fridge Thermometer,      46.125
2013-11-05 04:43:10 ,Basement Fridge Thermometer,      7.4375
2013-11-05 04:44:10 ,Basement Fridge Thermometer,      7.5625
2013-11-05 04:45:10 ,Basement Fridge Thermometer,      7.6875
2013-11-05 04:46:10 ,Basement Fridge Thermometer,     11.1875
2013-11-05 04:47:10 ,Basement Fridge Thermometer,      11.375
2013-11-05 04:48:10 ,Basement Fridge Thermometer,       7.875
2013-11-05 04:49:10 ,Basement Fridge Thermometer,     10.4375
2013-11-05 04:50:10 ,Basement Fridge Thermometer,          10
2013-11-05 04:51:11 ,Basement Fridge Thermometer,     43.1875
2013-11-05 04:52:10 ,Basement Fridge Thermometer,       46.25
2013-11-05 04:53:10 ,Basement Fridge Thermometer,       45.75
2013-11-05 04:54:10 ,Basement Fridge Thermometer,          46
2013-11-05 04:56:10 ,Basement Fridge Thermometer,      46.875
2013-11-05 04:57:11 ,Basement Fridge Thermometer,      7.5625
2013-11-05 04:58:10 ,Basement Fridge Thermometer,           9
2013-11-05 04:59:10 ,Basement Fridge Thermometer,          85
2013-11-05 05:00:10 ,Basement Fridge Thermometer,          85

The logging is supposed to happen every minute so any minutes with no 
logs means the temperature data was invalid (probably null).  But then 
there are readings like these three:

2013-11-05 04:41:10 ,Basement Fridge Thermometer,          85
2013-11-05 04:42:10 ,Basement Fridge Thermometer,      46.125
2013-11-05 04:43:10 ,Basement Fridge Thermometer,      7.4375

I know for certain there is no way the temperature inside the fridge 
went from 85 C to 7 C in two minutes!

So what is going on here?  Is this a problem with a rampant device on 
the wire, or the reader (a DS9490), or owfs?  If the values are 
checksumed then this seems like a software issue since any corruption of 
the data on the wire should have failed the checksum and been flagged as 
invalid.

Also, in case it helps, other 1wire sensors, including a family 10 
sensor, also get crazy readings so this is affecting multiple sensors.

Any guidance on resolving this would be appreciated.

Thanks,

Jeff

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