DS18S20 - Common Fail Symptoms?

[SteveD.]

Hi there,

I've got an old version 1 Dallas Wind/temp array running with lightning, solar and other temp sensors on the LAN. Last night, the temp sensor in the wind/temp array started recording wild fluctuations (-22F to 8600F and some "normal") for several hours.

I didnt catch it until I got home from work and by that time it had caused Wdisplay to hang up. A restart cleared the hang but the fluctuations came back and it was causing lock-ups when I tried to access the extra sensor graph where I view the 1wire sensors.

I've cleared "that" sensor from the program so it no longer looks for it and the program is behaving now.

My question is, is this a common type of fail mode for a DS18S20. I've had 'em blow out from a lightning strike but never "lose their mind". Can anyone give some feedback on what kind of failures you've seen?

Thanks,
Steve

 

[ericvic]

Steve,

I have not seen one fail in that way. I have seen them either completely disappear from the 1-Wire network or start giving CRC errors but not very strange temperature readings.

Eric

 

[SteveD.]

Hi Eric and thanks for the reply.

I was scared that I was going to get that reply. You might recall that I recently added that lighting struck solar sensor back to the LAN and am fearful that it's causing the "hitches".

BUT - Have you seen anything like this when the LAN is overloaded (running too many passive powered sensors?)

My setup is qty 3 DS18S20's, 1 solar, 1 lightning and the wind array. Approx 300ft of cable. All passive. I used to run a temp/humidity and the solar on supplemental and never saw a problem but after my last lightning strike seemed to follow my ground loop, I chickened out and dropped the supplemental. (Also not running the temp/humid board either).

Any insight?

Thanks,
Steve

 

[ericvic]

Steve,

Don't really have any good answers for you but I can tell you that you should be able to run many more sensors than you have on parasitic power.

Eric

 

[SteveD.]

OK Eric,

I'll try dropping the entire 1wire net off my 'puter today and just run my Lacrosse to see if the problem goes away. If it does, I'll start dropping off sensors (starting with the lightning struck solar.)

As always, thanks for your support.

Steve

 

[SteveD.]

Hi folks,
It turned out to be my solar sensor causing some kinda pull on the network. After dropping it out of the loop. Everything was fine. Thanks!

Steve