Hi list, Apologies for the slightly off-topic message but I figured someone here may have some suggestions for me on this non-owfs issue I am having...
I have a DS18B20 sensor located outside. It is in a location that is safe from water (unless it rains horizontally). My bus master reaches this sensor through a cat5 bus that has about 10 more sensors. The sensor, its pins, and the small PCB the sensor is soldered to, are all exposed (to wind and humidity, but not to direct water). Parasitic powered, and Vcc pin is floating (not connected to ground). This setup has been pretty stable (no 1-wire errors or bad temperature readouts in 6 months of operation). Last night there was heavy rain and thunderstorms in the area and for a period of about two hours I was getting the dreaded 85 degrees C from this sensor. All other sensors were fine during this time and did not report 85 degrees. The problem fixed itself a bit after rain and thunderstorms passed. I think it is humidity what causes the 85 degrees C readout since we've had a few warm and humid days/nights recently (but no rain) and I've gotten a few 85 degrees C readouts here and there from the same sensor. But nothing like last night when I consistently got 85 degrees C readouts for about two hours. Next time this happens I plan on grounding Vcc to see if that helps, but I also wanted to ask the list for theories on what could be causing these 85 degrees C readouts when it is humid (or when there are thunderstorms in the area). If grounding Vcc does not help I think my next step should be to protect from the elements the sensor, its pins, and the small PCB. Any ideas on how to accomplish this; is there some coating I can spray on the sensor's pins and on the PCB that will protect them from humidity? Thanks in advance for any suggestions. Cheers, Eloy Paris.- ------------------------------------------------------------------------------ Free Software Download: Index, Search & Analyze Logs and other IT data in Real-Time with Splunk. Collect, index and harness all the fast moving IT data generated by your applications, servers and devices whether physical, virtual or in the cloud. Deliver compliance at lower cost and gain new business insights. http://p.sf.net/sfu/splunk-dev2dev _______________________________________________ Owfs-developers mailing list Owfs-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/owfs-developers
