Flow sensor + safety / failure alerts?

[spooons]

Curious if the connection of a flow sensor can provide a safety mechanism if a valve is stuck open or there is a leak within the overall system?

My thinking is “if master valves are off, or if all non-master valves are off, and flow rate is > 0 then send an alert” or something along those lines.

Does this currently exist within the firmware or would this be something I would need to add myself?

I am looking at utilizing and customizing this amazing system for a small farm irrigation project and I want to make sure that in the event of a valve or pipe failure that I am not drowning a crop. Seems like it would be handy in someones yard too!

Thanks

[Ray]

The firmware currently does not use the flow sensor value to trigger any action — it only logs the flow sensor reading and displays it on the homepage. In the next firmware we may consider adding some basic functionality to trigger actions. But since different users may have different needs about how to use the flow sensor readings, it’s probably best to customize the firmware to suit your own need.

[Ryan Turnquist]

I second this idea. I think it would be extremely powerful to get alert via email for example when the flow sensor reads flow when no valves are on. In addition, I think it would be nice to get alerts when there is a 0 flow reading when the valves are on meaning the source water is not flowing (i.e. was mistakenly turned off).

[Comatose]

I’d rather a pressure low / pressure high limit. I think that if you could program in a system back pressure per zone then if the pressure was below this point you have a pipe break. Above this you have a blockage. But it would get complicated due to tolerances required and what if your incoming pressure fluctuates beyond your pressure reducing valve (if fitted) anyway thats what I’ve been thinking of putting into mine. Could also be done via “if flow exceeds value” but I have a few pressure sensors and I dont have a flow meter….

[bgonderi]

The high/low limit idea sounds interesting, but I agree that the tolerance issue would be my primary concern there. I’ve never experienced a blockage, but have experienced both a stuck open valve and a broken pipe, so my initial desire was simply for a functionality mention by Ryan (alert if zone(s) on but no flow, alert if no zone on and flow).

A few potential issues:

1. OS doesn’t currently appear to have any functionality for sending email. Not sure how much programming space adding this would consume.

2. How much potential system instability would be added by supporting email notifications? (i.e. what happens if email cannot be delivered immediately? What if remote email server is slow, or stops responding during some part of the email transaction? Sending email would require DNS lookups which may or may not work, may timeout, etc.). I would not want the stability of my irrigation controller to be adversely impacted by the addition of this functionality (although I definitely agree that it would be “nice to have”).

3. How much “leakage” do typical residential irrigation systems have (compared to the resolution of the flow meters)? I assume the systems aren’t 100% watertight, so may need a non-zero “all zones off” low flow threshold (similar to Comatose’s low pressure limit).

I don’t currently have a flow sensor (or the OS firmware supporting it), but it sounds like the flow data is only logged during zone operation, so there would be no information logged regarding item #3. Not sure if it would make any sense to add support for adding logging for some sort of min/max/avg value for this.

I’m not sure what else could be done to notify the user of a flow-related issue in the absence of email notification (if it were deemed too risky for whatever reason). The only thing I could think of with the current hardware would be to flash the backlight, but that is very likely to go unnoticed, as would a warning notice on the UI (as most people probably have the device mounted in some out-of-the-way location, and aren’t logging into the web interface every day).

Some sort of sounder/beeper/speaker could be added to the OS hardware which could perhaps alert the user to any sort of issue (flow-related, network connectivity, SD card full, etc.), and perhaps with the addition of “cloud” support, the email notification could be generated/handled from the “cloud” as opposed to the OS unit itself.

[Ray]

Although the firmware currently doesn’t support sending emails, there is actually a simple way to enable this, which I briefly mentioned in this forum post:
https://opensprinkler.com/forums/topic/external-access-without-dyndns/#post-39447
it’s by using PushingBox, which is very easy to use.

Flow data is logged during zone operation. Also, the status bar displays real-time flow rate. The real-time flow rate is not logged currently, but it should be pretty straightforward to log it periodically.

[PollieXmas]

Hi All,

I also like Comatose’s pressure monitoring. The pressure fluctuation can probably countered by only looking at pressure differences between starting pressure, operating pressure and final ending pressure (per station). That means you’ll have to add a delay between activating stations to get a proper reading which might have another knock-on effect when using a master zone to activate a pump as then you’ll have to use a different pressure algorithm altogether as the pump should compensate for pressure fluctuations during an irrigation cycle and you would not want all closed valves while the pump is running.

It’s a slippery slope, but I can sense a solution at the bottom 😉

This of course creates even more headaches for Ray who yet to provide separate rain and flow sensors and I of course would want two flow sensors so I can also monitor any high usage or slow leaks on my main line to the house and not just on the irrigation line 🙂

The problem with leaks is that your probably only know for sure after month three when the second high water bill arrives. This can be a hefty bill which is even worse when it co-incides with water restrictions, so well worth installing some sort of warning system.

Either way I would be keen on either solution.

Regards
Paul

[951calguy]

If it hasn’t been enabled yet, how hard is it to tie flow to every station and trigger an alarm if high/low flow? as I said before I can provide info on how a lot of the high end manufacturers work with flow.

[Ray]

I am interested in hearing ‘info on how a lot of the high end manufacturers work with flow’. Could you elaborate?

[951calguy]

Ray I don’t know if you remember Im the guy that sent you the flow meter/master valve setup. If we can communicate privately I can let you use my login info to my accounts with the most popular irrigation systems where you could see how the flow features work, like I said before I am very interested on these features.

[Ray]

Yeah, I do still have the box of flow sensors you sent me. Thank you very much for it. Perhaps you can send a support ticket (either written or phone) and we can continue the conversation there?

[Author]

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