Hi! Robert, for low power radio please see https://www.mysensors.org/ - framework based on arduino/raspberry pi and cheap radio NRF24L01 or RFM69. I'm using it for more than 2 years now and it's very reliable (NFR24L01 + MQTT gateway). On web site you will find a lot of ready to use examples with different sensors. Yesterday I give it a try and connected mysensors to weewx via MQTT and Node Red. Working so far!
Regards, Robert On Monday, January 30, 2017 at 5:52:41 PM UTC+1, Robert Mantel wrote: > > I'm interested in the MQTT standard, didn't really know anything about it, > but may migrate to that idea and skip the phant server step altogether, but > using the fileparse extention with the jsonp query of the phant server just > made things simple for me. > > As for the lower power radios I did consider using xbees, which I may do > at some point, but I'm not sure if they will save me enough power to > warrant the extra cost, we'll see how my experiment plays out. I guess I > would have to migrate from my BME280 because it's either SPI or I2C and I > haven't read anything about how to deliver that over an xbee radio > connection. What radio's are you using? > > On Monday, 30 January 2017 10:50:28 UTC-5, Bill Morrow wrote: >> >> Very nice. I considered flower pots for the radiation shield also, but >> then that wouldn't align with your snowflake theory, would it? >> >> I like both Sparkfun and Adafruit's ecosystem. Phant looks interesting. >> I'm reading temperature and humidity in the house using an Adafruit Feather >> Huzzah publishing over wifi to the MQTT broker. weewx subscribes to the >> MQTT broker to get the data. Powered by a wall wart, but the Feather has >> the capability of charging a battery. So in theory I could cut the cord >> there too. >> >> My main goal is to harvest power from the PV cell on the top of the >> lantern. It maxes out at about 25 mW at 3.2 volts. I should be able to >> easily get 30 mAh every day, and a lot more than that on a sunny day. My >> station averages about 25 mAh consumption per day. I've made no attempt to >> cut power consumption on board, e.g there is a small power LED that is >> always on. >> >> I'm working on a circuit provided by LInear Technologies: >> http://cds.linear.com/docs/en/design-note/dn491.pdf, which boosts almost >> any voltage to Li-ion charging levels. No success yet, mainly because of >> the difficulty of working with parts with millimeter dimensions. >> >> You're dealing with a much higher power regime. But sounds like you have >> some good power management strategies going. You might be able to reduce >> your power needs by going to low power radios instead of wifi? >> >> On Monday, 30 January 2017 11:20:17 UTC-4, Robert Mantel wrote: >>> >>> Hey Bill, no problem. I can't provide pictures right now but will when >>> I get home. I'm using an 8000 mAh battery I got from ebay (I may upgrade >>> to a 12000 mAh), that is connected to an Adafruit Solar Lipo charger. I >>> also bought a 6 volt solar panel from ebay or amazon, can't remember right >>> now, but the adafruit charger works best with a 6v panel. The charger >>> board has a connector for the battery, the solar panel and the load as well >>> as an older mini-usb connector to charge the battery from an ac usb adapter >>> if you just want to top up the battery when it's too low and it's really >>> cloudy. You can also configure the rate of charge with the addition of a >>> resistor to boost the charge rate to 1000 mA which is what I did. Most >>> lipo's can only handle a charge rate of 1C (C being the capacity of the >>> battery) so I'm well within the 8000 mAh that the battery could take charge >>> wise. I'm currently experimenting with how many days I can go without >>> intervention (hence the reason I may go with a larger 12000 mAh battery to >>> get more days of autonomy out of the weather station). Ideally I would >>> like it to run 24x7 without intervention. >>> >>> To save power I do with the Particle P1 redboard is that I have >>> configured it to run in manual mode, meaning I control the wifi and cloud >>> connections. Because I have a local phant server collecting the raw sensor >>> data from the redboard I have no need to connect to the cloud and because I >>> have it in manual mode I briefly turn on the wifi every 2 minutes to dump >>> the sensor data to my phant server in the house. Wifi is by far the >>> biggest power consumer so the more you can control that the better. I'm >>> waiting for a 6 dBi wifi antenna to put on the particle P1 because I've >>> noticed that sometimes the wifi doesn't connect where I have it placed >>> inside my shed. All the sensors are outside the shed of course, but I >>> wanted as much of the electronics sheltered from the elements for longevity >>> sake. The only active electronics I have outside is the BME280 sensor >>> inside my own home brew radiation shield I made out of flower pot trays. >>> >>> While I only post data to weewx every 2 minutes, the station is >>> processing data continuously, so rather than feed for example the current >>> wind direction and speed, I dump the average wind direction and speed over >>> 2 minutes to weewx. In a previous iteration of my weather station I had it >>> sleeping during each cycle but that proved to be a problem for getting >>> accurate rain readings because if the station was asleep it would miss a >>> bucket tip. So I went with a larger battery and then controlled the wifi, >>> which saves a ton of power. The system has a rescue mode so that if the >>> battery falls below 20% soc it will begin sleep cycles of 5 minutes so that >>> the solar panel can pump all the power into the battery until it rises >>> above that threshold and comes back online. So far so good, hasn't had to >>> do that yet, but it may tonight because we've had quite a few overcast days >>> lately. >>> Let me know if you want more specifics and I'll help fill in the blanks. >>> >>> On Monday, 30 January 2017 09:59:03 UTC-5, Bill Morrow wrote: >>>> >>>> Robert, can you share any details on the solar powered Redboard? My >>>> weather station is based on an Arduino Pro Mini, powered by an old Li-ion >>>> camera battery. The weather station sleeps most of the time, waking up >>>> briefly every 10 seconds or so to sample weather. I get about 2 weeks out >>>> of the battery, then swap it. >>>> >>>> It's all housed inside an old solar garden lantern and a container >>>> which originally held some delicious carrot ginger soup. It communicates >>>> with a Raspberry Pi 1 in the house via nrf24L01 radios, using the RF24Mesh >>>> libraries. The radio is pretty power hungry, and the main reason for the >>>> large sleep duty cycle. On the left of the case, you can see the antenna >>>> pointing at the base station in our house. >>>> >>>> >>>> <https://lh3.googleusercontent.com/-cf4BRy65O2w/WI9S_5UBXLI/AAAAAAAAEfY/YPV_pxfK36cppzaMq9XYPsbg0Lr7F0gKgCLcB/s1600/weather_lantern.jpg> >>>> >>>> The temperature sensor shield on the bottom is made from some sports >>>> drink bottles. >>>> >>>> My main project these days is developing a circuit which will use the >>>> small amount of power generated by the cell to keep the battery charged. >>>> I've done some measuring, and it should be enough. I've gone down the >>>> rabbit hole of tiny surface mount components, so making slow progress. >>>> >>>> Oh, and this is all supposed to be done under a zero cost budget! >>>> >>>> On Monday, 30 January 2017 10:33:58 UTC-4, Robert Mantel wrote: >>>>> >>>>> Seems like raspberry pi systems are like snowflakes...lol. I use a >>>>> solar panel charged battery powered Particle P1 Redboard from Sparkfun >>>>> that >>>>> I have an I2C BME280 (temp/pressure/humidity/altitude) sensor, a >>>>> rain/wind >>>>> set from sparkfun as well. The redboard sends weather data over WiFi to >>>>> my >>>>> Phant server every two minutes, I have a cron job on my Pi that does a >>>>> jsonp query to the phant server to retrieve the latest record and parse >>>>> it >>>>> out into a text file with the "* = *" pairs that fileparse wants. Then >>>>> my >>>>> weewx system running on my pi archives every 2 minutes. Not realtime, >>>>> but >>>>> good enough for my purposes. I also have steelseries gauges running as >>>>> well. Been a great learning experience and everyone here has been very >>>>> helpful. >>>>> >>>>> Many ways to skin the cat here. >>>>> >>>>> On Monday, 5 December 2016 04:32:46 UTC-5, Joaquin Lopez wrote: >>>>>> >>>>>> Hello, at the School we have this weather station >>>>>> https://www.raspberrypi.org/education/weather-station/ >>>>>> >>>>>> It would be possible to configure the weewx system to be able to >>>>>> receive the data from the different sensosrs of our weather estation? >>>>>> >>>>>> Thanks in davance! >>>>>> >>>>> -- You received this message because you are subscribed to the Google Groups "weewx-user" group. To unsubscribe from this group and stop receiving emails from it, send an email to weewx-user+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
