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For Sale Again! WBA-TH1M Sensirion SHT11 Temperature/Humidity Sensor Module - Page 2 — Parallax Forums

For Sale Again! WBA-TH1M Sensirion SHT11 Temperature/Humidity Sensor Module



  • WBA ConsultingWBA Consulting Posts: 2,927
    edited 2010-05-14 20:10
    Just as an FYI to anyone interested, I have now dropped to less than 50 modules left. Unfortunately, when my current inventory of SHT11s is depleted, I will be forced to purchase parts at the normal going rate of $25, so the cost of the module will go up to about $32 if I continue to offer it. I have a few hundred PCBs and plenty of the passives, so the sensor and building are the only expenses to have more.

    Andrew Williams
    WBA Consulting
    WBA-TH1M Sensirion SHT11 Module
    My Prop projects: Reverse Geo-Cache Box, Custom Metronome, Micro Plunge Logger
  • WBA ConsultingWBA Consulting Posts: 2,927
    edited 2010-06-10 16:29
    It has been a wonderful experience, but it is time to bid farewell to the $15 WBA-TH1M SHT11 Module. A recent large order by a company in France has depleted my stock. (as of writing this, Gadget Gangster still has about 17, get one while they last!) This has been a lot of fun, especially seeing how people are using my module. Here's a short list from the 300+ modules out in the world, where they have gone and what they have been used for:

    Weather station at the Missouri School for the Deaf
    Orchid Greenhouse monitoring setup in Texas (for an award winning orchid grower)
    Exotic plant greenhouse controller in Sebastapol CA
    Humidifier controller for a basement somewhere back east
    Controller/Datalogger for a warehouse AC system in Minnesota
    Scale model of an alternative energy home for a college project in Michigan

    Outside the US:
    Cave monitoring in Italy
    Equipment rack datalogger for some sort of weather tracking van in Perth, Australia
    Solar/wind powered home ventilation controller in Denmark
    Alternative Energy Class training aid for a school in Belgium
    Industrial AC efficiency meter in Bosnia (I had to doublecheck export restrictions for that order)

    Other places where my modules have went:
    Singapore, South Africa, Greece, India, Ireland, Turkey, and at least 20 of the US states.

    I have hundreds of PCBs left so will be making modules for large orders as they come through (the company in France may order more even at the higher cost, since it is still cheaper than them developing their own for example). I will also have a handful of the blank PCBs thrown on the freebie table at UPEW.

    My sadness over the SHT11 modules "end" will be shortlived, as my PowerTwig is actually going into production before UPEW and will be available for purchase at my table.

    Andrew Williams
    WBA Consulting
    WBA-TH1M Sensirion SHT11 Module
    My Prop projects: Reverse Geo-Cache Box, Custom Metronome, Micro Plunge Logger
  • steve_bsteve_b Posts: 1,563
    edited 2010-06-11 20:19
    Add to that list:
    Climate monitoring for weather radar in Canada.


    What's the best thing to do in a lightning storm? "take a one iron out the bag and hold it straight up above your head, even God cant hit a one iron!"
    Lee Travino after the second time being hit by lightning!
  • Timothy D. SwieterTimothy D. Swieter Posts: 1,613
    edited 2010-06-12 14:41
    Singapore? Perhaps that is the unit that I ordered through Gadget least I think I ordered the unit there.

    It is neat seeing your creations come to life and be of economic value to others.

    Timothy D. Swieter, P.E. - Prop Blade, LED Painter, RGB LEDs, 3.0" 16:9 LCD Composite video display, eProto for SunSPOT, PropNET, PolkaDOT-51
  • WBA ConsultingWBA Consulting Posts: 2,927
    edited 2010-06-12 19:17
    steve_b, thanks for the additional "where-used". It's been fun finding out how they are getting used.

    tim, that was probably you then as the Singapore unit was through GG.

    Andrew Williams
    WBA Consulting
    WBA-TH1M Sensirion SHT11 Module
    My Prop projects: Reverse Geo-Cache Box, Custom Metronome, Micro Plunge Logger
  • WBA ConsultingWBA Consulting Posts: 2,927
    edited 2013-03-04 22:58
    I was fortunate enough to acquire a large order that has allowed me have an excess SHT11 and SHT15 sensors, so I will be making more of both versions over the next few weeks. I already have all of the parts necessary, just need to build and test them. Pricing will be increased slightly from the original due to increases in the sensor cost, but still very attractive and much less than other SHTxx modules:

    WBA-TH1M Sensor Module with SHT11 sensor will be $24 shipped
    WBA-TH5M Sensor Module with SHT15 sensor will be $30 shipped

    Each will come with two 4 pin headers, one straight and one right angle. I should have about 70 left from this order and should have a 50/50 mix of the two versions. I will post again once I have modules built. My site with more details is still available:
  • LoopyBytelooseLoopyByteloose Posts: 12,537
    edited 2013-03-05 02:48
    If I were to buy these modules, I would use them in commercial greenhouse settings as a means to monitor temperature and humidity throughout the growth cycle. Ideally, it would be most economical to have them on an RS-485 network feeding to a computer that collects all the data and prepares it for transfer over the internet to a home office. To do that, I'd probably use a PIC with CANbus for each node with the sensor to provide data as something like 15 minute intervals unless the grower wanted a higher rate.

    Another CANbus network might provide control of ventilation, irrigation, and light insensity in response to out of bounds readings.

    And alternative project would be third-world pig farming. The pigs need to be cooled and the fans that do so are run from bio-gas generated by the pig waste. Usually, the process is done manually by the farmer than just keeps an eye of the pigs all day, but it is worthwhile to automate and to collect the data to see how the pigs fare with tighter control.

    I'd love to see some real data on how these units hold up in a tropical climate. I fear that the humidity sensor might not last long enough for it to be viable for agricultural applications. Fungus may grow on them and clog the unit, or they may occasionally be hit by water spray. The water itself might be hard water and the coat the unit with calcium deposits. And then there might be wear and tear from nitrogen fertilizer.

    One additional use might be to create a passive cooling system that has been used since the Roman Empire. An air intake is created via a 2 to 3 meter deep 15 meter tube that provides air and a nature convection tower draws the air through the building. Actually, the air is warmed in the winter as well as cooled in the summer, so the system can operate year round to reduce cooling and heating cost.

    It does take a house with some land, and the trick is to use about 4 300mm diameter corrogated plastic flex pipe (because the rough surface causes more turbulence and more heat transfer). It all goes into the crawl space under the house and then can be distributed to rooms as required.

    Having data record the temperature and humidity at the intake would be very helpful to prove its worth.
  • RS_JimRS_Jim Posts: 1,444
    edited 2013-03-05 05:41
    Tracy Allen should have data on longevity in ag environment.
  • LoopyBytelooseLoopyByteloose Posts: 12,537
    edited 2013-03-05 06:11
    Thanks.. I will keep that in mind. A lot of more and better processors that are suited for these agricultural applications are now on the market for less cost than ever.

    We have a very active orchid export industry in Taiwan that is interested in monitoring greenhouses, and there are quite a few produce growers as well.

    I've friends that are pig farming in Chiang Mai in Northern Thailand and rely on the biogas powered fans with an evaporative cooling wall as the pig farm is off the grid. An automated system just needs to run of the car battery that starts the salaged car engine that runs the fans, the existing altenator keeps it charged.

    So, there are real uses out here in the less developed world.
  • WBA ConsultingWBA Consulting Posts: 2,927
    edited 2013-03-05 11:26
    Using the SF1 filter cap with the sensor allows for much greater longevity in high humidity environments. One of my customers that has a very high humidity environment but does not use the SF1 cap (for reasons of immediate response) has said that he changes out the sensors about once a year, but they are usually still working.
  • Tracy AllenTracy Allen Posts: 6,553
    edited 2013-03-05 12:09
    Humidity is a tough measurement in those environments. The sensor can recover from water in the form of condensation and sprays, but things like sulfur sprays or ocean salts or (pig?) dust are highly detrimental. Sensirion sells a gore tex cap (the SF1) that fits on top of the SHT11 or SHT15, and it can be made to project out through an opening in an enclosure or encapsulant. That protects it from direct insults, but you still don't want junk to be deposited on the filter, which would clog it and distort the vapor pressure. In agricultural settings I've mounted it in a louvered weather shelter, such as the Davis 7714 .
  • LoopyBytelooseLoopyByteloose Posts: 12,537
    edited 2013-03-05 22:03
    @Tracy Allen
    I am curious as to how long these last with adequate protection... 1 year, 5 years?

    I can install a scheme with adequate protection similar to what you recommend, and I can place the devices where they will be less abused.
  • Tracy AllenTracy Allen Posts: 6,553
    edited 2013-03-05 22:48
    Here's an SHT15 sensor with SF1 cap that ended up incorporated in a wasp nest. The wasp liked the weather shelter. In the tropics, of course the shelter will house myriad geckos!

    Loopy, I checked with the supplies coordinator for one of my customers who has installed 740 SHT15 sensors in the Davis 7714s since August 2011. He said he hasn't received any back or reports of failure in that time period. I hasten to add that is not the same as saying there were no failures, because word does not necessarily come back from field crews. Nevertheless, I would certainly hear about it if there had been any significant problems or gaps in the data sets. I did get quite a few back from earlier batches, but that turned out to be an issue unrelated to the sensor itself. These are deployed in agricultural fields, mostly in California, and they are subject to sprays and road dust, but not tropical humidity or pillars of lightning.

    I've had some installed and working for longer time periods, anecdotal evidence, but not 5 year statistics.

    Do note that the accuracy falls off at high RH. 100%+/- 5% means that you can see unadjusted readings over 100%. These work best at moderate RH.
    480 x 360 - 45K
  • LoopyBytelooseLoopyByteloose Posts: 12,537
    edited 2013-03-06 03:00
    For the novice, 100% RH reading might be considered important, but I have learned that the true utility of the humidity data in conjunction with temperature is to anticipate a dew point barrier.

    With the orchid growers, a drop below dew point might condense water on the plant leaves and do actual damage.

    For the pig growers, the pigs might get a bit wet and need the cooling fans shut off to prevent a chill.

    Dew point is also very important in a lot of other areas. Anyone painting houses outdoors needs to take it into consideration, especially when using new water based exterior house paints. And for automotive body shops in high humidity regions, this data is quite important.

    Another one is that I had a screw manufacturer here that was ignoring the humidity when packing his stock for delivery. It arrived in Germany rusty and each package of 1000 was one screw short. The trick for shipping is quite simple. Move your stock into a air conditioned environment under about 25 degrees centigrade and it won't have a 'dew point event' in transit. This is what I also recommended to a local orchid grower that was have in transit moisture damage. So, this is not a market for real-time temperature, humidity, and dew point positioning.

    The truth is that even though I have thought about this and tried to help out a few people over about a decade, I haven't found a way to make any real money with these applications. But somebody that either works through a government agricultural extension or an agricultural univeristy (like UC Davis) should find a potental following. The biggest orchid grower in the USA is in Homestead, Florida and he visits Taiwan nearly every year. But there are others, one just south of San Francisco. In fact, the biggest crop on a cash basis in the San Francisco Bay Area counties is flowers.

    Roses in the San Francisco Bay Area are subject to mildew due to local fog, and there are large commercial rose growers. Also, there is a huge following of competative amaturer rose growers that compete for prizes that might really love to monitor these conditions... especially with an SMS warning feature.
  • JLockeJLocke Posts: 351
    edited 2013-03-06 07:15
    I've been playing with a temperature/humidity data logger for a couple of years. I have a master unit with micro-SD, a DS1307 for the time, a Parallax SHT11 module, and an XBee. It has a 4x20 LCD. The outside unit has another SHT11 module, and an XBee. Since it is outside, it's powered by 3 AA batteries. I get about 70 days on a Fry's brand AA. The unit sleeps most of the time, and every 10 minutes or so, it wakes up and transmits the temperature and humidity. When the master receives the outside data, it then transmits its own temp/humidity to the downstairs unit. The downstairs unit originally had a DS1620 for the temperature (no humidity info from downstairs). The latest rev replaced that with a DS18B20. That unit has a 2x16 LCD, and is powered by a wall-wort. When the downstairs unit receives the upstairs info, it sends the current temperature to the master unit. Every quarter-hour the current data is written to disk in a .CSV format. I pull the disk usually once a week and import the files into an Excel spreadsheet I've set up.

    I originally set out to build an upstairs/downstairs thermostat, but after collecting some data, have seen that the real problem is that I don't have two separate AC units (upstairs/downstairs). I may still one day add another module for HVAC control. Here's an example of a couple of days; one particularly hot day, and one day recently.
  • WBA ConsultingWBA Consulting Posts: 2,927
    edited 2013-03-06 09:03
    JLocke, your project definitely has my interest and I would love to see pics and more details of your setups (post details in the projects forum, hint, hint). I do plan on building a weather station with my daughter as a science project and your setup sounds a lot like my notes and sketches in my notebook.
  • JLockeJLocke Posts: 351
    edited 2013-03-06 16:53
    OK... check the Projects subforum for my ThermoProp project.
  • WBA ConsultingWBA Consulting Posts: 2,927
    edited 2013-04-08 16:37

    SHT11 Modules are now available!
    I will be building up the SHT15 modules very soon. For now, send me a PM if you are interested. I may be adding a PayPal button to my site linked below once I get all of them built.
    WBA-TH1M Sensor Module with SHT11 sensor will be $24 shipped
    WBA-TH5M Sensor Module with SHT15 sensor will be $30 shipped

    Each will come with two 4 pin headers, one straight and one right angle. My site with more details is still available:
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