Trixology
Weather => Weather Hardware/Measurement => Topic started by: elagache on October 20, 2014, 09:53:14 PM
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Dear WeatherCat subscribers to my Davis station "mellar-drama."
Sufferin' succotash, I got another station sensor error this morning. Once more it was the remote temperature and humidity sensor that had errors. Alas, it happened at exactly the same time, early morning, the coldest part of the day. That gave me a sinking feeling.
So the first thing I did was check the voltage of the 123 battery in the ISS. Heavy sigh, it had dropped from 3.23 volts to 3.1 volts and I replaced that battery 6 days ago.
I did a little checking around and the most likely culprit is the super capacitor that allows the ISS to store solar power. They are dirt cheap, but I don't have the skills to solder on a circuit board like the one in the ISS. So I punted and ordered a new ISS circuit board from Scaled Instruments. Given my symptoms, replacing that circuit board should finally get rid of this problem once and for all.
Anybody have some other thoughts that I should consider?
Maintaining a weather station is so much . . . . fun!?!??? . . . (http://www.canebas.org/WeatherCat/Forum_support_documents/Custom_emoticons/clonk_head.gif)
Cheers, Edouard [cheers1]
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From 3.23 to 3.1 in 6 days, in my estimate, would not be cause for alarm. The IR drop from a fully charged battery is not linear. That last bit of topping off when charging the battery is packing those little electrons under pressure into a very crowed subway car. When you first open the door, the little buggers can't wait to get out of there. Later it gets a little more orderly and as the voltage drops a little, the circus in your instruments slows down a bit. Also, the first ones out of the subway head straight for those little resistors, capacitors and chokes to fill the rides before the lines start forming.
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Howdy Herb and WeatherCat Davis station troubleshooters,
From 3.23 to 3.1 in 6 days, in my estimate, would not be cause for alarm.
Well, as far as I understand how a Davis station works - yes it is. The super-capacitor is supposed to store up enough power so that the station can run 24/7 without using the battery at all. We've only had 2 cloudy days in the past 6 and hey, this is California, so there is plenty of solar power available. So this battery shouldn't have been drained at all.
Further evidence to back up my pessimistic conclusion is that this is the second time I've had sensor error problems. The first time was on October 11th. Once more replacing the battery caused the problem to go away for a few days. Two identical appearing events in less than 2 weeks basically rules out bad batteries.
;) . . . . . . Besides it is all your fault Herb! In the old days I only bought 123 batteries in a 2 pack. Now that you've convinced me to buy them in an 8-pack, there are plenty of them in the house. I suppose my ISS saw all that bounty and became a gluten!! . . . . [lol2]
Oh well, my ISS circuit board has already shipped. I hope it will arrive before I run out of 123 batteries!! (http://www.canebas.org/WeatherCat/Forum_support_documents/Custom_emoticons/eek2.gif)
Cheers, Edouard [cheers1]
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Lol! OK, Edouard. Sitting on the edge of my seat, to see how this drama reaches its climatic end!
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Howdy Herb and WeatherCat Davis station caregivers,
Lol! OK, Edouard. Sitting on the edge of my seat, to see how this drama reaches its climatic end!
Well, this morning I got another station sensor error just like I got on Monday. So it seems that the super-capacitor is consuming a 123 battery every 4 days or so. Worst still, I decided to have the ISS replacement circuit board shipped by the post office. Normally that doesn't take more than a week and I placed the order on Monday. It won't arrive until next Wednesday. So I might burn two more 123 batteries before I can replace the circuit board. That certainly would have paid the difference between UPS and the post office rates. (http://www.canebas.org/WeatherCat/Forum_support_documents/Custom_emoticons/D%27oh.gif)
Oh well, . . . .
Cheers, Edouard [cheers1]
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Dear WeatherCat Davis station troubleshooters,
My poor weather station continues to suffer from da' dreaded ISS battery "eatin'" syndrome. I replaced the ISS circuit board and enclosure on Monday and to my disgust once more I was getting sensor errors from my anemometer and remote temperature-humidity sensor. As before this was happening in the pre-dawn period where the battery is coldest and there is no solar power to help out. I pulled the battery and replaced it. Just like every battery before it, the 123 battery dropped from 3.23 volts to 3.15 volts in just 5 days.
Since the ISS circuitry is completely new it can be eliminated as a suspect, so what's left? Could the solar panel have gone flakey somehow? The only other possibility is that the sensors are now a greater drain. I checked the long cable run from the temperature-humidity sensor under the deck - no signs of damage. I took apart the shield and inspected the sensor - it looks brand new and I haven't touched it since installation.
I think I'm licked and will call Davis tech support on Monday to see what they suggest. I also started another thread on WXForum:
http://www.wxforum.net/index.php?topic=24235.0 (http://www.wxforum.net/index.php?topic=24235.0)
If any of you get a clever idea on this one, please send it my way!!
Cheers, Edouard [cheers1]
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Sorry to hear it, Edouard. Finding obscure hardware bugs can make a young man go bald quick.
All I see to suggest is, again, 3.15v is still a very good battery. I'd look for other causes of the error than battery drainage issues. I've tested my batteries with the Fluke both going in and coming out. When the batteries are done, that voltage is near or below 2v. Perhaps you're getting radio interference.
I hope Davis can tell you something that helps!
Buena suerte, buddy.
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If I remember right Edouard, you are connected to the computer via an Envoy? As a test, can you replace it with a console? (Just to completely eliminate that bit of the system).
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Howdy Herb, Stu, and WeatherCat fans,
Sorry to hear it, Edouard. Finding obscure hardware bugs can make a young man go bald quick.
All I see to suggest is, again, 3.15v is still a very good battery. I'd look for other causes of the error than battery drainage issues. I've tested my batteries with the Fluke both going in and coming out. When the batteries are done, that voltage is near or below 2v. Perhaps you're getting radio interference.
I have gotten some replies from the folks on WXForum and the latest diagnosis is that most likely the super capacitor on the second ISS circuit board from Scaled Instruments is also bad. Certainly an unexpected fluke, but it is the most plausible explanation. Herb you may be correct that the batteries aren't dead, but what appears to be the problem is with that super capacitor not charging up properly it is demanding more current than the 123 batteries can provide. After 4-5 days of that load, the batteries can't supply the load. Of course you see the first symptoms at the point when the battery is under the most stress: before dawn when temperatures are coldest and there is no solar assist.
Nobody on the WXForum saw any reason to suspect the sensors and I took down my temperature-humidity probe and it looks brand new. I also checked the voltage on the solar panel and according to the folks of WXForum once more, it is performance within the expected range.
The suggestion over there was for me to contact Scaled Instruments and see what they think. If they agree with the diagnosis and agree to replace the board perhaps that's the most hopeful solution to be found.
If I remember right Edouard, you are connected to the computer via an Envoy? As a test, can you replace it with a console? (Just to completely eliminate that bit of the system).
Well, yes I could and did that when all these problems first started up. Eventually the console also ran into trouble. In addition, WeatherCat is reporting specific sensor errors. The last time WeatherCat was reporting that both the temperature-humidity probe and anemometer were generating sensor errors. The rain gauge wasn't reporting any errors though. If the Envoy was able to receive the details of the sensor errors, that would seem to rule out the Envoy as the cause. So I really think the problem is on the ISS end of things. If the diagnosis is correct, I'm just having a run of really bad luck.
Oh well, .. . .
Cheers, Edouard [cheers1]
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Dear WeatherCat viewers of my ISS battery eatin' soap opera,
This morning I got in touch with Ryan Wilhour, the owner of Scaled Instruments. I sent him a link to the WXForum discussion that concluded the most likely cause of my troubles was a second failure of the super-capacitor in the ISS circuit board he had sold me. He not only agreed with the diagnosis, but offered me a most generous solution. If I shipped out the broken board he sold me via something UPS which has a tracking number, he would send me a new board via priority mail at his own expense!! No deposit required!
I put back the original 5 year board so that I wouldn't lose any data in the transition. It was very cranky, but finally it started transmitting data correctly. I got the other board out via UPS this afternoon and Mr. Wilhour promised to ship out the new board this evening! So with any luck at all I won't be burning too many more 123 batteries! I've already had to start using the second 8-pack! (http://www.canebas.org/WeatherCat/Forum_support_documents/Custom_emoticons/eek2.gif)
Cheers, Edouard [cheers1]
P.S. ;) . . . . I hope that Herb finds some other sucker to help boost his battery commissions!! . . . [lol2]
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I hope that Herb finds some other sucker to help boost his battery commissions!!
Ha ha! I know he could use the cash to replace his ISS that the brainless and heartless eejits stole from him.
As for you, I hope this nails it for you.
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Everything crossed :)
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Shoot, Edouard? if I did get a commission from Amazon it would likely be paid in batteries. First batch, I'll send 'em to ya!
Blick, It's getting close to time to fix my mangled ISS (actually, it's just a rain gauge at the present). I sold some stock in my company and will be calling Davis soon.
Edouard, there may be a drought, but look out for inflation in Calie's economy. I'm about to send 'em (Davis) some money.
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Edouard, well, I hope the new board does the job. But if I may offer another possible solution??..
I'm in Indiana and from Octember to January, we are socked in with cloudy skies, and my ISS gets very little solar charge time. I am also running an old ISS that has been out there for over 8 years now. I don't have any extra sensors on the ISS and it's one of the wireless versions. I also have had issues this time of year, or rather as soon as the night time temps start to fall under 20?F, which still won't be for another month or so. This Winter is predicted to be very cold with little precipitation, so I'm looking at the battery freezing again.
A brief history of batteries: My Uncle, who worked for P.R.Mallory (they became Duracell) in research and development from WWII until he retired in the late 90s was always a good source of information about batteries and what they did, specifically how they did in different environments. He always told me to check the environmental specifications of the batteries I used if there was a problem with outdoor use. These are lithium batteries and this type of battery was designed to work with a generally fixed constant low current drain over a very long time period, perfect for the ISS as a rule.
Over the years I have ordered or bought locally the 123 batteries from wherever I could find them. And usually each time I would end up with a different manufacturer's product. So here's what I found looking back, a lot of battery manufacturers have a lot of differing temperature specifications and only a few are made with sub-freezing temperature specifications. And some just don't hold up in the cold. The most expensive 123s I found didn't hold up, and the cheapest didn't hold up when they got cold. The voltage drop often fell below 2v on a brand new battery after it got frozen once. The best battery I have found was the Duracel Procell PL123BK (12pack from Amazon, and usually inexpensive). The operational temperature range for these batteries is -20?C to 75?C (-4?F to 167?F). So far these batteries have outlasted anything I've used (including the direct replacement from Davis). You just need to pay attention to the manufacturers temperature curves.
I used to swap out my ISS batteries in December, but so far, haven't for the last three years on the Duracells. Time will tell. Also, when you change your batteries, wipe off the battery terminals with a little bit of alcohol to clean the contacts, it helps a lot.
My view on things, hope it helps a little.
Good Luck
Doc
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Thanks for the info Doc.
I have a question about the operating range of the 3 volt batteries. Testing them without a load (at the store before you buy, or at home before you put them into the ISS) what is the acceptable range of voltage? I have a Nuon battery on my shelf that I picked up for US$1 somewhere that tests at 3.15 volts. Should I be tossing that one our before it even gets a chance to be used?
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Here ya go, Blick.
[interesting]
Product Data Sheet - Duracell Ultra DL123A. (http://ww2.duracell.com/media/en-US/pdf/gtcl/Product_Data_Sheet/NA_DATASHEETS/Li123_US_OS.pdf)
Found on this page. (http://ww2.duracell.com/en-US/Global-Technical-Content-Library/Product-Data-Sheets.jspx?icn=Prim/PrimNav/Product-Data-Sheets&cc=Primary)
? what is the acceptable range of voltage? ?
I take it that you mean "what is the lowest acceptable end of the range of voltage?"
From the data sheet, 3.2 to 3.3v is new battery voltage. The acceptable range of voltage to the device using the battery is from that voltage at the outset to the cutoff voltage designed into the device. My measurements (if memory serves me correctly) of the voltages of removed batteries, after the device no longer functioned, were somewhere close to 2v, give or take. It will differ slightly between devices.
In the graph below you'll see that in a continuous discharge use, the voltage drop off is rather quick after full discharge, but a battery with 3v can still have considerable life in it if the discharge rate is low, which should be the case for the ISS.
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Hi Doc, Blick, Herb, and WeatherCat Davis station caregivers,
Edouard, well, I hope the new board does the job. But if I may offer another possible solution??..
Thanks for the thoughts, but it really seems unlikely that the problem is the batteries. This station just had its 5th anniversary and I've never had problems like this before. Since this station is located in mild northern California, the 123 battery isn't even close to its operating limits. The lowest recorded temperature since the station has been up is 30.4˚ F.
The replacement ISS circuit board and enclosure are supposedly on the mail truck as I type. As soon as it comes in I'll make the swap. However, I won't be sure that things are really cured for another 5 days. The sensor errors have always happened about 5 days after a fresh 123 battery was installed. I just hope that indeed I've been jinxed by a factory board with another bad super capacitor and this new board will finally break the jinx! (http://www.canebas.org/WeatherCat/Forum_support_documents/Custom_emoticons/pray.gif)
Cheers, Edouard [cheers1]
P.S. Thanks Herb for getting the battery specs. It is more than I probably would ever care to know, but it is interesting to see how these batteries perform.
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Dear WeatherCat subscribers to my Davis station "mellar-drama." (http://www.canebas.org/WeatherCat/Forum_support_documents/Custom_emoticons/SOS_help.gif)
The replacement ISS circuit board and enclosure arrived this afternoon as the tracking number promised. I've swapped in the new part and so far everything is looking good. However, I've got to get past that dreaded 5 days of battery eatin' to be absolutely sure. So I'm keeping my fingers crossed! (http://www.canebas.org/WeatherCat/Forum_support_documents/Custom_emoticons/pray.gif)
Cheers, Edouard [cheers1]
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Hi edouard
Hope all goes well you might want to cross your toes too [biggrin]
Let hope this takes care of it
cheers
[cheers1]
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Thanks for the battery information Herb. I was looking at similar charts for a dozen different brands.
In all the tests I saw, the Duracell 123 performed at or near the top. There is less of a difference in performance between brands at low discharge rate than at a high rate. I cannot see that there is any difference in specifications between Duracell Ultra and Duracell Procell. They appear to be the same battery in different pajamas. The manager of a local batteries and bulbs store told me there is only one plant that makes all 123 batteries and that all are alike so buy the cheapest one you can find. However, the data suggests that brands perform quite differently in the field so after taking all this into consideration, I will be purchasing the Duracell Ultra. It performs well, is easy to find and I don't have to buy them in 8 or 12 packs (I don't have any devices that use this battery other than my ISS).
That being said, I live in a harsh winter climate and my original battery from Davis lasted 7 years before I replaced it. Davis told me the average life of their battery is 2-3 years.
Edouard, I hope you have nailed this thing finally and that you get it running properly, just in time to records what's happening during a rain storm.
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Dear Randall, Blick, and WeatherCat station caregiver support group . . . :)
Thanks for the sympathy! So far everything is working fine but that was expected.
Edouard, I hope you have nailed this thing finally and that you get it running properly, just in time to records what's happening during a rain storm.
We aren't expecting rain until Thursday. I took advantage of the limping along situation to do some maintenance of the wooden brackets supporting the ISS. They sure needed a few coats of varnish. I'll try to repaint the bracket for the anemometer before the rain hits - it also could use some "luv" . . . .
After that I indeed hope to leave the station alone and have it collect lots and lots and lots of rain!! (http://www.canebas.org/WeatherCat/Forum_support_documents/Custom_emoticons/rain_happy.gif)
Cheers, Edouard [cheers1]
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Dear WeatherCat subscribers to my Davis station "mellar-drama."
Can you believe it!?!?! Day 6 after once more swapping the ISS circuit board and enclosure and this time . . . . no more batteries being eaten!! [tup]
I varnished the bracket supporting the ISS. I've repainted the bracket supporting the anemometer so everything is buttoned up for winter.
Better still, we got a little rain today! (http://www.canebas.org/WeatherCat/Forum_support_documents/Custom_emoticons/rain_happy.gif)
Now all I need a whole lot more of da' stuff!!! [rain2]
Cheers, Edouard [cheers1]
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no more batteries being eaten!!
(http://www.morrisgarage.com/misc/stuff/crowd_clapping.gif)
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Good news then, glad it's working out!
Doc
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Howdy Doc and WeatherCat station caregivers, . . . .
Good news then, glad it's working out!
It's been two weeks since swapping the second ISS board and enclosure and everything is working as it once did. I don't have to worry about the station anymore! [bounce]
That's good, because there are - always - things to worry about! [rainyluck]
Cheers, Edouard [cheers1]
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Dear WeatherCat subscribers to my Davis station "mellar-drama."
*Sniff* I gave the all clear too soon. This morning once more sensor errors from the temperature/humidity probe and the anemometer. The event lasted for about 30 minutes started at 1am and once more there was exactly the same number of errors for each instrument.
We got some rain this morning (http://www.canebas.org/WeatherCat/Forum_support_documents/Custom_emoticons/rain_happy.gif) so I couldn't check the battery until around noon. Under load the battery was down to 3.03 Volts. This battery has been in the station for only 12 days, so it looks like the same scenario. I have another thread on the WXForum:
http://www.wxforum.net/index.php?topic=24426.new;topicseen#new (http://www.wxforum.net/index.php?topic=24426.new;topicseen#new)
However, this time I've decided to try something else. I have two temperature/humidity probes. So this afternoon I swapped the data cables. If it is the probe under the deck that is causing my problems, it should kill the battery in the Wireless Temperature/Humidity Station instead while leaving my ISS alone. If the battery still dies, that strongly suggests that my anemometer or perhaps the rain gauge or solar sensors are to blame.
Of course I obligingly put another battery in. Sure hope you are enjoying your battery commissions Herb!
Oh well, . . . .
Cheers, Edouard
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Dang! Sorry to hear this. Keep us posted. Even Herb will be unhappy to hear this.
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Sorry 'bout that, Edouard. Two boards down and a peck of trouble to go. Keep going, though. You'll find it. I guarantee it'll be the last thing you check!
[tup]
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Dear WeatherCat subscribers to my Davis station "mellar-drama."
Thanks Blick and Herb for the sympathy. I have successfully stumped the crew on WXForum as I suspected I would. It is definitely time to call the folks at Davis Instruments and see if they have heard of anything like this happening. Beyond that I must confess to have that itch to buy a whole new set of instruments and ISS to get this nightmare to go away.
Oh well, . . . . .
Cheers, Edouard
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Dear WeatherCat subscribers to my Davis station "mellar-drama."
I just got off the phone with Davis Instruments tech support. I asked the fellow if there was any way that the sensors could be causing the battery to drain. He flat out said that is just not possible. There is precisely one way for a Davis ISS to exhibit the symptoms I'm seeing: yet another defective super-capacitor. Could I have been so unlucky that I would have gotten two replacement ISS circuit boards with bad super-capactors?
I just sent an email to Ryan Wilhour at Scaled Instruments. I'll be very interested in learning what he think this . .. . . . . .
Stay tuned!! (http://www.canebas.org/WeatherCat/Forum_support_documents/Custom_emoticons/tune_in_TV_emoticon.gif)
Cheers, Edouard [cheers1]
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Edouard, have you checked to see if the solar panel in the ISS is actually charging the super-cap? I had to replace mine a couple years ago. This could explain the problem.
Regards,
Dave
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I was about to suggest that too, take your solar panel off and expose it to sunlight while checking the output voltage. I don't know if the ISS you have is wireless, I'm assuming that it is. On occasion I have run a power cord out to my ISS during times of extreme cold and powered the board through the test power plug inside the ISS housing. I also run a small incandescent light bulb in there too for heat in the winter. Both remote power and heat lamp are switched from the house.
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Dear Dave, Doc, and WeatherCat subscribers to my Davis station "mellar-drama."
First, the latest developments in this gripping drama . . . . . (http://www.canebas.org/WeatherCat/Forum_support_documents/Custom_emoticons/eek-sign.gif)
I got back on the phone with Davis and got another guy who admitted . . . he has no idea what is going on! (http://www.canebas.org/WeatherCat/Forum_support_documents/Custom_emoticons/scratch_head.gif)
He had a talk with the Davis engineers and came up with a good idea. The battery collection must be loose.
Just one small problem. The battery connection cannot possibly be loose. This is a brand new ISS board. I checked it anyway and send the result back to Davis, so the ball is back in their court.
Edouard, have you checked to see if the solar panel in the ISS is actually charging the super-cap? I had to replace mine a couple years ago. This could explain the problem.
Interesting. According to this tech guy, the solar panels never fail. He had never seen one. I am a bit suspicious. However, I checked the voltage on the solar panel and it is 2.5 Volts. That is supposed to be a perfectly healthy value. Still, that isn't a measure of current under load so I'm not convinced just yet.
I was about to suggest that too, take your solar panel off and expose it to sunlight while checking the output voltage.
That's what I did. Do you agree Doc that a 2.5 Volt value is adequate?
That's today's installment. . . . . . . having "fun" yet? . . . [rolleyes2]
Cheers, Edouard [cheers1]
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So much for Davis Tech support! When I had a problem a few years back I measured open circuit voltage of about 0.8 volts and dropping down to around 0.7 when connected to the ISS. Davis Tech guy said "yeah, that sounds about right". I did not believe him. The new panel produced something around 2.5 as I recall. I just went out and measured my ISS panel voltage at 2.20 under a solid overcast sky, so 2.5volts in direct sunlight would be good. Plugging and unplugging the ISS connection showed only about a 10 millivolt change as the current required is very small once the capacitor is charged.
So, time for a new theory.
Dave
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Dear Dave and WeatherCat Davis station troubleshooters,
So much for Davis Tech support!
Thanks for your own reports . . . Yes, indeed Davis instruments are very miserly about power so they can run on amazingly small amounts of power.
So, time for a new theory.
Yes, indeed and there one more piece of information that suggests an alternative. There is a fellow on the WXForum complaining about ISS circuit boards with problems with the power switching circuitry. There has to be some logic that switches from the solar panel, to the super capacitor, and finally to the battery if there is no other source of power. If that logic is working incorrectly, like for example not switching to the battery early enough, then the ISS would shutdown.
It may well be the case that my long cable run to my temperature/humidity probe may require a bit more current than usually expected. Eventually my old ISS circuit board had its super-capacitor fail. After all, it is 5 years so. What I have tried to replace with are newer boards with updated firmware. I wonder if these newer boards cannot handle that additional current draw properly and are not using the battery quickly enough.
However, that gives me another sneaky idea. It turns out that the 6382 transmitter is exactly the same circuit board as the as the ISS transmitter. However, it has no solar panel and thus presumably never uses the super-capacitor. I'll see if I run into problems with my temperature/humidity probe plugged into that. If I don't, I might just buy a second one of those and use that as my ISS transmitter instead something with the solar panel. Right now I replace the 123 battery 4 times a year on the 6382 transmitter. If I can make my present setup work with just that change, I'll gladly pay Herb his battery commission and get rid of this super-capacitor nonsense completely.
For now I'll just keep monitoring the situation and see what happens. I just hope nothing goes haywire during the rain event we are expected starting this weekend.
Cheers, Edouard [cheers1]
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Dear WeatherCat subscribers to my Davis station "mellar-drama."
Alas this problem insists on continuing even on Thanksgiving. Here is what I found this afternoon when checking WeatherCat:
(http://www.canebas.org/misc/Voila_images/Station%20sensor%20errors%202014-11-27.jpg)
This rules out the assumption that it was the long cable run to the thermometer under the deck that's the problem. Since there are two sensors having problems at once, it also seems unlikely that it is a sensor error, especially since this is now claiming that a thermometer that has never given errors before is to blame.
Definitely something really strange going on here . . . . (http://www.canebas.org/WeatherCat/Forum_support_documents/Custom_emoticons/scratch_head.gif)
Oh well . . . . . .
Cheers, Edouard [cheers1]
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Dear WeatherCat subscribers to my Davis station "mellar-drama.",
*Sniff*, like clockwork I had another batch of sensor errors early in the morning. Here is outage between midnight and 2am:
(http://www.canebas.org/misc/Voila_images/External%20temperature%202014-11-28.jpg)
and here is the WeatherCat Live data report:
(http://www.canebas.org/misc/Voila_images/WeatherCat%20channels%202014-11-28_08-28-42_AM.jpg)
I gave up and "fed" the ISS another battery. Since I have suspicion that the problem has something to do with the circuity that switches from the solar panel, to the super-capacitor, and the 123 battery, I left the solar panel disconnected. I'm hoping that the station will switch to the 123 battery and that should give me months to come up with another solution.
Oh well, . . . . . (http://www.canebas.org/WeatherCat/Forum_support_documents/Custom_emoticons/shrug_shoulders_confused.gif)
Cheers, Edouard
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It's still possible that it is interference. Weaker Xmitter current leads to weaker signal strength.
Just supposing?
[computer]
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Hi Herb and WeatherCat station troubleshooters,
It's still possible that it is interference. Weaker Xmitter current leads to weaker signal strength.
I believe this possibility can be ruled out because the episodes do stop after a while with no intervention on my part. The last episode lasted from midnight to 2am. From then on the ISS provided valid data. That's why I believe it must have something do to with the ISS power switching circuitry. At midnight there wasn't enough power to get data from the temperature/humidity probe and the anemometer. Something was automatically switched at 2am so that there was now enough power. This problem happens at a very odd battery voltage: ~3.12 Volts. I'm guessing that is some sort of trigger point for the power switching logic.
The pattern has been so amazingly regular that I really suspect some change in the logic that Davis uses to switch from solar panel, to super-capacitor and finally to battery. The ISS board of 5 years ago could provide power to my temperature/humidity probe under the deck. I'm guesses that Davis tweaked the power settings to extend the battery life and now there isn't enough power for those long cable runs under some conditions when the ISS is powered by the super-capacitor. When the ISS board finally switches to the battery, everything if fine. That explains why there isn't enough power when the battery is indeed in the prime of its life as you had pointed out.
Cheers, Edouard
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Dear WeatherCat subscribers to my Davis station "mellar-drama."
Well it took 7 days instead of 6, but alas this morning my station did its sensor error thing:
(http://www.canebas.org/misc/Voila_images/Live%20Data%202014-12-06.jpg)
Fortunately, the rain gauge wasn't effected by the sensor errors because we got a little more rain overnight . . . (http://www.canebas.org/WeatherCat/Forum_support_documents/Custom_emoticons/rain_happy.gif)
When I got to the ISS things were slightly different. Instead of the battery being down to 3.1 Volts, it had gone down to 2.95 Volts. That still should have been more than enough to keep the station going, but it does show that disconnecting the solar panel has some effect on this problem.
There was one other interesting bit of evidence. When I replaced the battery, I got a low voltage warning. That suggests to me that the super-capacitor is completely discharged.
Nonetheless, something is very strange here. The Davis tech I spoke with insisted that with the solar panel unplugged the ISS could run for months and Blick's station did just that.
I'm feeling like my problem has to be related to the extensions to the temperature/humidity probe cables I added. Somehow Davis has changed either the circuitry or firmware on the ISS circuit board and under some conditions it cannot provide sufficient current to reach those sensors over that long cable.
I think I've have to swallow my pride change the configuration of my station to eliminate those extended cables.
Oh well, . . . . . (http://www.canebas.org/WeatherCat/Forum_support_documents/Custom_emoticons/shrug_shoulders_confused.gif)
Edouard
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2.5 volts from the solar panel is just what I get, so I think you are OK there. At this point, I'd be pulling all the circuit boards that are outside, including the sensors and checking everything for old solder connections. I'd be looking at each one with a strong magnifier or microscope or I'd just resolver the thing just to be sure. I'd check every circuit tracing on the board to make sure you don't have any cracks. I would pull every remote sensor wire and replace the connector on all of them with fresh and newly crimped connectors. For those I can get too, I would go into each sensor and resolver each solder point.
Old solder can corrode over time and get covered with oxides, to get through the electricity needs more and more current to get past the oxidized solder. at the same time this puts a heavier drain on the batteries as well.
Doc
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Dear Doc and WeatherCat Davis station troubleshooters,
Thanks for the advice, but I'm reasonably confident that the problem has to be those extensions I made to both temperature/humidity probes. I've heard from both a Davis tech and a member of the WXForum that the electronics in the temperature/humidity probes are extremely sensitive to cable length and since I setup the station 5 years ago, Davis has discontinued selling the 6-conductor splicing kits and is closing out the 6-conductor extension kit. Since the kit Davis sold was 40 feet max, and I'm running more like 100 feet . . . . As both guys exclaimed, I'm amazed it ran for so long!
So I need another mousetrap. I looked carefully at what other options I might have to allow me to use a unmodified Davis temperature/humidity probe. I would like to keep my anemometer where it is, so that basically limits me to positioning the ISS no more than 100 feet from where the anemometer is now (I have to call Davis and confirm this.) The anemometer is on the south side of the house where alas the central air conditioner condenser exhaust fan is also located. So I need to make sure to put this temperature/humidity probe far enough away so that the thermal wake of the air conditioner won't distort the readings.
I'm going to head out and try to plan all this out, but my current hypothesis is that I should reverse my current scheme. Instead of having a long cable from my temperature/humidity probe under the deck. I should run all the other cables to that location under the deck and replace the sensor there. To do that I would abandon the ISS electronics and instead use a Davis 6382 transmitter as my ISS transmitter. According to Davis they are exactly the same board inside, just tell your console or Envoy that there is an ISS at that frequency ID, plug in your sensors and you are good to go. Another thing I learned is that these boards have a jack for a Davis AC adapter, so I'll switch from solar power to AC power. I'll run a extension cord to provide the power from the other end of the deck. The other thing I would like to do is add a small electric fan. I have a feeling the air under that deck can become stagnant if there is very little wind, and as a result, temperature values can be off because of the deck causing a thermal gradient.
I'm about to head out and see how to make this all work! . . . . Wish me luck!
Cheers, Edouard [cheers1]
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Ambitious plan but well thought out. You are a capable guy and if you can pull yourself away from worrying about the Buick you should be able to put it to rest.
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Dear Blick and WeatherCat regular soap opera watchers, . . . . .
Ambitious plan but well thought out.
Unfortunately the weather and other "issuez" are going to force me to put this project on hold.
You are a capable guy and if you can pull yourself away from worrying about the Buick you should be able to put it to rest.
Speaking of my trusty wagon, I finally had to spill the beans of the miserable fate of my wagon on the largest forum of Buick muscle car guys. That finally brought out the engine builder to make a public statement on the matter for the first time. So far everything is civil, but . . . . definitely trying to thread lightly over there.
Never a dull moment . . . . (http://www.canebas.org/WeatherCat/Forum_support_documents/Custom_emoticons/juggle.gif)
Cheers, Edouard [cheers1]
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Dear WeatherCat subscribers to my Davis station "mellar-drama."
I have all the Davis parts I need to move the ISS transmitter from its present location on the end of the rain gauge to a 6382 enclosure that will be powered by an AC adapter. Alas, trying to get all the conduits and brackets ready is taking much longer than I would have preferred. In the meantime, the darn ISS board started giving me sensor errors when I replaced the battery yesterday! :(
I sure hope Herb is enjoying this battery commission because he should be making a fortune on me! (http://www.canebas.org/WeatherCat/Forum_support_documents/Custom_emoticons/eek2.gif)
Oh well, . . . .
Edouard
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Dear WeatherCat subscribers to my Davis station "mellar-drama."
Could it be that deliverance is at hand? . . . .
It was a terrific struggle, but today I finally completed relocating my station transmitter from the Davis factory position at the end of the rain gauge to a 6382 enclosure next to my temperature/humidity probe under the deck. This meant running 3 50+ foot data cables from the anemometer, rain gauge, and solar radiation sensor back to under the deck. It took a lot of prep work, but today I actually spliced the data cables, moved the ISS transmitter board into the new enclosure and replaced the old temperature/humidity probe with a new fan-aspirated assembly (fan is also AC powered via a universal AC adapter.) I had to buy an extra Davis AC adapter to power the ISS board since solar power was no longer available.
This afternoon, I powered up the ISS board and waited . . . . . At first the console couldn't find the instruments, but eventually everything worked normally. I ran some water through the rain gauge and used a blower to get the anemometer moving just to be sure. I then deleted the data logger in the Weather Envoy using the Davis WeatherLink software so all erroneous data was purged before WeatherCat was launched. Everything has been working fine since.
I'll write-up the changes in gory detail, but I've had to put some other projects on hold that are now pressing. So it may be while.
In a word Phew! (http://www.canebas.org/WeatherCat/Forum_support_documents/Custom_emoticons/phew.png)
Cheers, Edouard [cheers1]
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Congratulations. I love it when a plan come together. This should eliminate your spare change going to Herb for battery commissions and is actually a much better arrangement for data transmission.
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Good job, Edouard! [rockon] With all the spare change you've sent my way, I can retire! ? Oh, wait. [rolleyes2] I am retired. ? Never mind.
Can't wait to read the gory details.
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Dear Blick, Herb, and WeatherCat soap opera viewers,
Thanks! It was a terrific struggle but clean living prevailed! ;D
Everything looks just fine after a bit over 24 hours. The one pleasant surprise is the responsiveness of the thermometer now that it is fan aspirated. I was a bit concerned when I first put the thermometer under the deck that the air was a bit stagnant. I removed some of the baffles in the radiation shield to improve the air flow. Clearly that wasn't good enough.
The only downside with using the Davis fan kit is that the motors aren't supposed to last very long when running at 3 volts. So I'll have to come up with another fan in the not too distant future. The guys on the WXForum suggested trying a fan for PC. Sounds like a good idea since those fans run a long time and have to be tough.
Cheers, Edouard [cheers1]
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I'm a bit slow catching on. Why did you want to move the transmitter board to under the deck? Doesn't the 6382 have its own transmitter? (I have one on order as an add-on to my station.) Glad it all worked out, but am confused about the new setup.
Speaking about the fan aspirated retrofit, I did this. Can't tell if it is still operating. I know it requires pretty direct sunlight to make it work. Suspect that the solar panel is not putting out the "juice" that it should be.
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Dear LesCimes and WeatherCat soap opera viewers,
I'm a bit slow catching on. Why did you want to move the transmitter board to under the deck? Doesn't the 6382 have its own transmitter? (I have one on order as an add-on to my station.) Glad it all worked out, but am confused about the new setup.
The reason I had to make this change is that I had been running a 50+ foot data cable between the temperature/humidity to the ISS transmitter when I put up the station 2009. It turns out that Davis no longer recommends extending the data cables at all on the temperature/humidity probe. It is likely to cause problems. Last fall, my station started to generate sensor errors after I replaced the ISS transmitter, and I believe Davis made some changes in the past 5 years and caused that long temperature/humidity data cable to generate errors (even if it had worked for 5 years.) I didn't want to relocate any of my instruments, so I basically used the same strategy in reverse. Instead of running 1 long data cable from the deck to my other instruments, I ran 3 long data cables from my rain gauge, anemometer, and solar radiation sensor back to the temperature/humidity probe. According to Davis tech support, all those instruments work just fine with longer data cables. I then moved the ISS transmitter into a 6382 enclosure. I was able only buy the enclosure from Scaled Instruments so I saved a little money.
Speaking about the fan aspirated retrofit, I did this. Can't tell if it is still operating. I know it requires pretty direct sunlight to make it work. Suspect that the solar panel is not putting out the "juice" that it should be.
Do you have the daytime only fan setup or the 24 hour version with the additional batteries? According to the tech support guys at Davis, the solar panels basically never wear out. So if you aren't hearing the fan motor, odds are something else is wrong. There are reports on WXForum and elsewhere that the Davis motors that you buy today are poorly constructed and just won't last very long. So replacing the motor with another Davis one is most likely a costly mistake.
Cheers, Edouard [cheers1]
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Davis no longer recommends extending the data cables at all on the temperature/humidity probe.
Odd. I emailed them about this same thing, extending the cable on 6382 which I ordered last week. I expect I will need to locate the transmitter, which comes with 2' cable connecting to the sensor, a short distance from the sensor unit in order for the signal to reach my Console. Davis tech said it can be extended. Hmm, we shall see. Hopefully I won't need the extension or if I do the extension will be within tolerances. Thanks for the info - helpful. Alternatively, they sell a relay to extend the transmitters reach. Expensive, but it would work.
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Do you have the daytime only fan setup or the 24 hour version with the additional batteries?
I retrofitted the fan, so it doesn't have batteries, just the solar panel. So it runs only when the sun is shining on it. I haven't investigated it closely to see if indeed it is no longer operating. Need to find time on a bright sunny day to go out to the unit and look/listen closely. Hopefully it is still operational. If not, then what your saying is that it is likely to be the fan motor. Bummer. Would really like to upgrade to the 24 hour fan unit, but that requires a totally new VP2 with the feature included. Something to save for.
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It was a terrific struggle but clean living prevailed! ;D
This is the key to most successes in life. [tup]
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Dear LesCimes, Blick, and WeatherCat Davis fans,
Davis no longer recommends extending the data cables at all on the temperature/humidity probe.
Odd. I emailed them about this same thing, extending the cable on 6382 which I ordered last week. I expect I will need to locate the transmitter, which comes with 2' cable connecting to the sensor, a short distance from the sensor unit in order for the signal to reach my Console. Davis tech said it can be extended. Hmm, we shall see. Hopefully I won't need the extension or if I do the extension will be within tolerances. Thanks for the info - helpful.
I'm a bit confused. You were considering extending the cable between the temperature/humidity probe? Davis still sells the 6 conductor extension cable but only as a close-out:
http://www.davisnet.com/weather/products/install_cables.asp (http://www.davisnet.com/weather/products/install_cables.asp)
It may be okay for the Soil sensors, but the techs I spoke to at Davis were really against extending the temperature/humidity cable. They buy the actual sensor from another company and that company has made it clear that these cables need to be kept as short as possible.
I retrofitted the fan, so it doesn't have batteries, just the solar panel. So it runs only when the sun is shining on it. I haven't investigated it closely to see if indeed it is no longer operating. Need to find time on a bright sunny day to go out to the unit and look/listen closely. Hopefully it is still operational. If not, then what your saying is that it is likely to be the fan motor. Bummer.
If you made this upgrade a long time ago, the motor should be of the better quality type Davis used to have. However, these motors do operate in a tough environment. They won't last forever.
Would really like to upgrade to the 24 hour fan unit, but that requires a totally new VP2 with the feature included. Something to save for.
Actually you can just upgrade to the FARS probe. Scaled Instruments parts out Davis VP2 stations and sells just the FARS setup:
https://www.scaledinstruments.com/product/davis-6153s-24hr-solar-powered-aspirated-shield-for-pro2/ (https://www.scaledinstruments.com/product/davis-6153s-24hr-solar-powered-aspirated-shield-for-pro2/)
It is expensive at $250, but that's still a small fraction of replacing the entire station.
Cheers, Edouard [cheers1]
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Thanks, Edouard, for the tips. I'll look at that option from Scaled Instruments for a new fan.
Yes, a person at Davis sent me a link for cable extensions. http://www.davisnet.com/weather/search_product.asp?pnum=7876 (http://www.davisnet.com/weather/search_product.asp?pnum=7876) I'm not convinced he was paying close attention to what I was asking. He answered my email addressed to the sales department. I also email the tech department at Davis to get a different perspective. That guy also said the cable could be extend but he thinks I'll be able to connect wirelessly, i.e. that the distance won't be too far. So, I ordered the sensor and will verify it is calibrated the same as my VP2 ISS (I presume it will read the same) and then move the new sensor to the final location further from my house, hoping that the signal will be strong enough to reach the Console in the house.
Appreciate the input. Helpful.
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Dear WeatherCat fans of Davis stations,
Just a quick heads up. Running the daytime fan aspiration setup at 3 volts via a universal AC adapter is known to shorten the life of the Davis motor, but this morning I walked by the temperature/humidity probe and the motor is already "rattling" much louder than it was when I first installed it . . . . 6 days ago. ::)
So it seems these fan motors are indeed of a poor quality. I was planning to replace it with a PC case fan as these are inexpensive, tough, and run on 12 volts that my adapter can also supply. Looks like I'd better start shopping for one!
Cheers, Edouard [cheers1]