Alarms with Flow Sensors

[pghreefer]

Hello.

So i am new to APEX, but so far everything has been pretty easy to setup. I recently purchased 4 flow sensors (2 for emergency drains and 2 for return pumps). I need to help configuring the system to send me alerts based on GPH seen at the sensor.

For instance i would like a alert if the flow sensors on my emergency drain sees anything greater than 1 GPH.

So i have two inputs tied to the corresponding emergency drains, ED_Left and ED_Right. If i click on one of them and go to the advanced tab, under "Max Alarm", i click the checkbox for "Set Trigger Value" and my value is set to 1.

Is there anything else i need to do to get alarms? I have my email/text info setup and that works as i get alarms for the salt probe and other things. I let water flow down the emergency drain for 5 mins and never received a alarm.

I am missing something?

 

[RussM]

Did you see a flow reading while doing that test?

Flow sensors have a minimum flow amount they can read. If the flow going down that emergency drain was too low, it might not show anything.

 

[Rick's Reef]

@pghreefer, what did you find out with the alarms and emergency drains?

I set one up last night on a new tank, not to alarm but to shutdown a return pump if FEmerg > 100 (FEmerg is the 1" FM sensor on my overflow drain). The flow was measuring >100 on my Display, but the pump never shut off. I didn't debug further (like add an alarm) because I ran out of time. But before I go too far, I am curious if you or anyone else have this capability enabled.

Thanks,
Rick

 

[jml1149]

I do the same thing, absolutely. For my skimmer, I added the following line:

IF F_RET < 100 THEN OFF

Where F_RET is my return flow. This turns my skimmer off when my return pump is off. Should be similar for your application. Can you post your code? Happy to help if I can!

 

[ca1ore]

I would be careful about what you trigger with flow readings. I've now had two of my sensors lock up. Removing, disassembling and a good cleaning resuscitated them, but for a while the flow readings were zero.

 

[jml1149]

I would be careful about what you trigger with flow readings. I've now had two of my sensors lock up. Removing, disassembling and a good cleaning resuscitated them, but for a while the flow readings were zero.

Agree, if you get crud or some chaeto etc. in the sensor it may lock up.

However, since this is the emergency drain, and only used ideally in an emergency...shouldn't be an issue. Although you're never going to test it... And really if the emergency drain is flowing, it's doing its thing, so maybe I'd just set an alert before I shut off the return pump? You might consider setting an alert for flow through the emergency drain, then adding an optical sensor above that to shut off the return pump incase both drains are clogged.

 

[ca1ore]

Fair enough, though in my case I went a different route to accomplish the same thing. The emergency drain in my external box only 'engages' if the water level climbs high enough to overflow the stand pipe; thus, I put an optical sensor that will trigger if the water level rises. Not measuring water flow through the emergency directly, but probably more reliable (though perhaps splitting hairs).

 

[ca1ore]

I'm actually more interested in measuring flow though the open channel (drain #2 in the BA). That drain will regularly see a trickle (as opposed to the emergency staying dry), but it would be good to have a way to know if that trickle increases to a torrent. I've yet to come up with an approach I like to accomplish that .... though I do have a few thoughts.

 

[Rick's Reef]

@ca1ore - good advice about not shutting off the return pump with too much flow through the emergency pump, however, I have 2 return pumps with 2 separate returns on separate electrical lines for redundancy. 1 pump feeds the chiller and then the tank and the other feeds directly to the tank with a tee off to my GFO/Carbon cartridge and calc reactor. So, I figure if the emergency drain is triggering and over a certain value, I would turn off the less important pump. However, I also have high water float switch in the top of my overflow so really I guess I could rely on only that one.

I decided not to put a flow meter on my open channel drain, but since I have a flow meter on the main drain and the emergency, I can at least get a ballpark estimate by subtracting the 2. Although I don't think the Apex could do the math in an IF statement, can it? I don't think so but you cold use a couple of If's on virtual outlets to set a trigger.

I did put a short stretch of clear acrylic pipe on my open channel so you can see a rivulet of water draining down when it is tuned just right. You can see the pipe here but the pumps were off when I took this picture. Now, this is a new setup, so we will see how quickly this thing gets gunked over in regular operation...