24-04-2016, 22:41
(23-04-2016, 22:45)Wizza Wrote: [ -> ]Have posted a couple of photos of my receiver station, finished and mounted into a plastic instrument case ...Congratulations!
Very good job!
24-04-2016, 22:41
27-04-2016, 10:46
Passive Cooling for the TX Enclosure
After running the receiver station in its new enclosure for almost a week now, I had noticed that the top of the case was a little warm on the rear LHS, which is right above the heatsink on the powersupply. Nothing too concerning, but warm none the less. So I decided to cut open a 52mm hole and install a 60mm fan guard. For now it is merely an air vent, as the case has absolutely no ventilation otherwise. I think this should be enough to solve the problem. If I cut over to battery power and run down the battery somewhat, and also turn on the LCD backlight, the power supply heatsink runs at about 38 degrees when the chargig circuit comes in. So not too bad. If it is an issue next summertime, I'll simply install a 60mm fan directly below this fan guard.
[attachment=653][attachment=654][attachment=655]
{click on photos to enlarge}
After running the receiver station in its new enclosure for almost a week now, I had noticed that the top of the case was a little warm on the rear LHS, which is right above the heatsink on the powersupply. Nothing too concerning, but warm none the less. So I decided to cut open a 52mm hole and install a 60mm fan guard. For now it is merely an air vent, as the case has absolutely no ventilation otherwise. I think this should be enough to solve the problem. If I cut over to battery power and run down the battery somewhat, and also turn on the LCD backlight, the power supply heatsink runs at about 38 degrees when the chargig circuit comes in. So not too bad. If it is an issue next summertime, I'll simply install a 60mm fan directly below this fan guard.
[attachment=653][attachment=654][attachment=655]
{click on photos to enlarge}
07-05-2016, 02:18
5.1V DC Buck Power Supply for Raspberry Pi
Saturday morning, and time to tinker in my workshop and a little bit of relax time. During the week I have been experimenting with a 'buck' type power supply module for the Pi3. The theory was to step down the internal 12v power supply to 5.1v, after the battery backup module. This would give me the required 5.1v power supply to run the Raspberry Pi while implementing "uninterruptable power' for the whole system (WeatherDuino RX station and the Pi3).
After a bit of searching and looking around, I purchased a DC-DC buck power supply module from Altronics (in Aust) - part no. Z6334
Refer here - http://www.altronics.com.au/p/z6334-dc-d...40v-input/
This module will take an input of 3-40V DC and output 1.5-35V DC at 3A max. Sounded just what we need. First inspection of the unit revealed a module that was very well manufactured, with nice solder pads on each end for the DC input and output. The output voltage setting is via a nice little multi-turn potentiometer, so its pretty easy to dial up the voltage you want and get it spot on.
I set the output to 5.1v via the onboard pot and did some bench testing. The unit performed as advertised and the output was very stable, with only a very slight 0.02v ripple under no load. Running temperature of the module under a 300-400mA load (the Raspberry Pi 3) was only a little over ambient at about 30 deg C.
I identified a location to mount the 5v power supply module in the RX case, and installed a short piece of silicon fuel tube over the end of the SLA battery mounting plate, using a couple small dabs of ShoeGoo (amazingly handy stuff to have in the workshop). The 5V PSU simple slides into place and is held firm by the silicon fuel tube. Fitted a 2.1mm DC power socket on the rear for the output and we were done.
To get the power supply to the Raspberry Pi 3 I cut down a micro USB lead and fitted a matching 2.1mm plug to the end. Note here that when you are wiring on your DC plug, you need to short together the data lines (wires) in the USB cable, which tells the device (the Pi3) that it has a power supply connected and not a computer USB port and not to try to negotiate power current draw with the host (this happens automatically when we plug into a computer USB power and the current is negotiated and reduced so as not to damage the computer USB port.
[attachment=659]
{click photo to enlarge}
In this case we want the Pi3 to draw as much power as it needs. Bench testing showed that the Pi3 drew about 300-400mA with a USB keyboard and mouse, HDMI output to a screen and the WeatherDuino station attached. The current varies a little as write activities to the SD card and CPU loads comes in and out. So we shouldn't be stressing the 3A module with this sort of current draw.
After a couple of quick checks, all came to life as expected, and it is all running well. When testing and setting up sensors outside, it's nice to be able to unplug the RX station and simply take it with you, running on the internal power supply. This should also give some protection to possible corruption of the SD Card in the Pi3 in the event of a power outage.
[attachment=660] [attachment=661] [attachment=662]
{click photos to enlarge}
Saturday morning, and time to tinker in my workshop and a little bit of relax time. During the week I have been experimenting with a 'buck' type power supply module for the Pi3. The theory was to step down the internal 12v power supply to 5.1v, after the battery backup module. This would give me the required 5.1v power supply to run the Raspberry Pi while implementing "uninterruptable power' for the whole system (WeatherDuino RX station and the Pi3).
After a bit of searching and looking around, I purchased a DC-DC buck power supply module from Altronics (in Aust) - part no. Z6334
Refer here - http://www.altronics.com.au/p/z6334-dc-d...40v-input/
This module will take an input of 3-40V DC and output 1.5-35V DC at 3A max. Sounded just what we need. First inspection of the unit revealed a module that was very well manufactured, with nice solder pads on each end for the DC input and output. The output voltage setting is via a nice little multi-turn potentiometer, so its pretty easy to dial up the voltage you want and get it spot on.
I set the output to 5.1v via the onboard pot and did some bench testing. The unit performed as advertised and the output was very stable, with only a very slight 0.02v ripple under no load. Running temperature of the module under a 300-400mA load (the Raspberry Pi 3) was only a little over ambient at about 30 deg C.
I identified a location to mount the 5v power supply module in the RX case, and installed a short piece of silicon fuel tube over the end of the SLA battery mounting plate, using a couple small dabs of ShoeGoo (amazingly handy stuff to have in the workshop). The 5V PSU simple slides into place and is held firm by the silicon fuel tube. Fitted a 2.1mm DC power socket on the rear for the output and we were done.
To get the power supply to the Raspberry Pi 3 I cut down a micro USB lead and fitted a matching 2.1mm plug to the end. Note here that when you are wiring on your DC plug, you need to short together the data lines (wires) in the USB cable, which tells the device (the Pi3) that it has a power supply connected and not a computer USB port and not to try to negotiate power current draw with the host (this happens automatically when we plug into a computer USB power and the current is negotiated and reduced so as not to damage the computer USB port.
[attachment=659]
{click photo to enlarge}
In this case we want the Pi3 to draw as much power as it needs. Bench testing showed that the Pi3 drew about 300-400mA with a USB keyboard and mouse, HDMI output to a screen and the WeatherDuino station attached. The current varies a little as write activities to the SD card and CPU loads comes in and out. So we shouldn't be stressing the 3A module with this sort of current draw.
After a couple of quick checks, all came to life as expected, and it is all running well. When testing and setting up sensors outside, it's nice to be able to unplug the RX station and simply take it with you, running on the internal power supply. This should also give some protection to possible corruption of the SD Card in the Pi3 in the event of a power outage.
[attachment=660] [attachment=661] [attachment=662]
{click photos to enlarge}
07-05-2016, 10:42
Nice work Wizza. Are you on WeatherUnderground?
07-05-2016, 12:17
(07-05-2016, 10:42)spudstrawb Wrote: [ -> ]Nice work Wizza. Are you on WeatherUnderground?
WeatherUnderground is what I had in mind. Next step of the project for me is the outdoor station (the TX unit) and getting my sensors mounted in their permanent positions. Everything is setup in temp locations at the moment. Still contemplating ideas and final locations, and have to consider both cable lengths and physical locations. I know I'll work something out in the end, and have a few thoughts at the moment. Was planning to get my sensors sorted first, before I join WeatherUnderground. Not sure how they work, if you keep going off-air, while your still in planning and build stage..????
08-05-2016, 01:47
WU will just send you an email, saying your station is offline after a few hours.
(07-05-2016, 12:17)Wizza Wrote: [ -> ](07-05-2016, 10:42)spudstrawb Wrote: [ -> ]Nice work Wizza. Are you on WeatherUnderground?
WeatherUnderground is what I had in mind. Next step of the project for me is the outdoor station (the TX unit) and getting my sensors mounted in their permanent positions. Everything is setup in temp locations at the moment. Still contemplating ideas and final locations, and have to consider both cable lengths and physical locations. I know I'll work something out in the end, and have a few thoughts at the moment. Was planning to get my sensors sorted first, before I join WeatherUnderground. Not sure how they work, if you keep going off-air, while your still in planning and build stage..????
08-05-2016, 08:56
Campbell Scientific Radiation Shield
I found a nice looking dual louvered radiation shield from Campbell Scientific, which arrived during the week. Found time yesterday to pull it out of the box and give it a look over. All looks really well made, with powder coated aluminium bracket, stainless bolts and fittings. Installing the SHT11 sensor was a breeze and it all went to together easily and pretty quickly. Have the sensor on test and the readings already look more 'smooth' and consistent. Happy with this radiation shield and definitely worth a look if your in the market for a good quality unit.
[attachment=663] [attachment=664] [attachment=665] [attachment=666]
{click photos to enlarge}
I found a nice looking dual louvered radiation shield from Campbell Scientific, which arrived during the week. Found time yesterday to pull it out of the box and give it a look over. All looks really well made, with powder coated aluminium bracket, stainless bolts and fittings. Installing the SHT11 sensor was a breeze and it all went to together easily and pretty quickly. Have the sensor on test and the readings already look more 'smooth' and consistent. Happy with this radiation shield and definitely worth a look if your in the market for a good quality unit.
[attachment=663] [attachment=664] [attachment=665] [attachment=666]
{click photos to enlarge}
08-05-2016, 09:53
Oh wow, that is a very good looking Radiation Shield. What sort of price tag does this have? Are you thinking of putting in a fan as well? How do you think you might go about this?
08-05-2016, 10:16
(08-05-2016, 09:53)Palmyweather Wrote: [ -> ]Oh wow, that is a very good looking Radiation Shield. What sort of price tag does this have? Are you thinking of putting in a fan as well? How do you think you might go about this?
Was around the $140 mark, from memory. Still determining final location of sensors and that's my next stage of the project - setting up TX station and outside. I wasn't going to install a fan, and was considering the open space on the southern side of our property (southern hemisphere), which is predominantly shaded. If I needed a fan, I was thinking that I could get maybe a 40mm or 50mm fan into either the top or the bottom, after a bit of cutting and modification, but hopefully wont be required.
Mark R
08-05-2016, 11:41
WeatherUnderground - I went ahead and setup an account this morning on WU. Programmed our new station ID and password into CumulusMX and rebooted the Raspi. WU still reporting no update from weather station. I wonder if a 'person' at WU needs to approve / activate our new account..????