[jcodybaker]

The wifi is neither great nor awful. My Pi3 is not more than 30 feet from the wireless AP (an Apple 802.11ac AirPort Extreme), but if I were to draw a straight line it does go through a lot of old wood flooring and siding. The signal quality (iwconfig) in linux generally lists a quality of around 29/70. Since putting it on the independent power supply it seems to stay connected consistently and work well.

That 60 VA supply seems to work well.

[jcodybaker]

PTC removed. My OSPi v1.43+ didn’t have that specific chip. I followed the photos in Power pi and OsPi Separately. The 1.43+ didn’t have the 150 chip highlighted in the photos, but seemed to have two or three 050 chips stacked. I can confirm it seems to have had the desired effect and both Pi and all zones still work.

As for why I went with the rPi 3, I wanted wifi and figured onboard would be cheaper, easier, and better supported than a USB adapter. I may ultimately multi-task the pi into some other purposes as well.

I’m doing drip irrigation for vegetable gardens and put a valve in each of 10 beds. The valve per bed is almost certainly overkill in retrospect, but I didn’t want to dig up the yard twice and it seemed easier to have each bed connect to a single distribution pipe. I hadn’t appreciated the durations required for drip irrigating; if I want each bed watered during the morning hours its going to require having a few go at the same time.

I purchased a 60VA (2.5A @ 24VAC) supply from eBay but it was lost in the mail. The seller of the 60VA transformer from eBay also seems to have a store with the item listed. The documentation on that transformer lists the unloaded output as <= 30v. Despite their less than appealing name and poor quality picture, they’ve been pleasant enough to work work with and have sent a replacement for the one lost in the mail. After a week and a half of waiting for that, I got impatient and Amazon same-day’ed this Elk TRG2440 40VA to get my system up in the mean time. The voltage while unloaded on that ELK TRG2440 was 27v and seems to work well.

[jcodybaker]

Ok, issue at least partially and painfully solved. Reboots were power related, but it looks like my tests/program/setup were too much for the 500ma supply from the store. To test I was trying to run 4 zones + a master at the same time. Hooking the pi up via the micro-usb be was a mixed blessing. The pi stayed up during the whole test, but the valves shut after 30 or so minutes. It seems my valves (Rain-bird CP075s) pull 190ma each, and with five running it was just too much for the transformer. I’m assuming when the Pi was running off the OSPi power, the power would dip, it would reboot/freeze, the valves would close, and the transformer power would recover. With the Pi independently powered, it went until the transformer burnt itself out 🙁 .

I’ve ordered a more power transformer from the internet and will be more careful about running too many zones at once in the future. Its still not clear if the wifi issues were related to the OSPi or poor reception. I suspect in at least some cases I was mistaking the wifi issue for a reboot/freeze since there’s no display hooked to the Pi.

[jcodybaker]

Yeah, it definitely seems like it’s something power related. I’m seeing reboots as well, especially while the zones are active. Since both provide power, can I attach the micro-usb while the OSPi header board is connected?

[jcodybaker]

Ray et al.,

Thanks for the info. This may be a red-herring; since I’ve posted this I’ve noticed wifi drop-outs even when no zones are engaged.

That said, if I want to power the pi directly via that micro-usb, do I need to modify the OSPi to disable its 5v supply?

Doing a bit of research I ran across this describing the additional power requirements, especially regarding the built-in wifi. ( http://raspi.tv/2016/how-much-power-does-raspberry-pi3b-use-how-fast-is-it-compared-to-pi2b ). The description said that using the built-in wifi seemed to use 40mA idle and 100mA at peak. I’m not sure how that compares to the USB wifi dongles.

I’m running Ubuntu 15.10 on my pi. I don’t see anything especially relevant in my console log about the dropouts. I’m going to setup munin to log/graph wifi signal. My hope is that should let me figure out if this is genuinely correlated to the sprinkler timing or just periodic crappy signal.

[jcodybaker]

I can confirm it works well with the Raspberry Pi 3. I’m using the newest OSPi and the 24VAC transformer sold on the site. The mounts aligned without issue. The built in wifi seems robust enough that it works from the back yard.

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