Temporary Flow Meter

[rsumner]

Anybody ever plumbed their system to allow for the temporary use of a flow meter? I have quote a segments of plumbing on my new tank design that I would like to measure flow, however I only need to measure it once I set it up and probably once a month or so after I clean the pumps to insure that my ball valves are setup correctly for the diversion percentages I want on my manifold. I originally planned on buying about six 1-inch Apex probes, but I've found them to be really unreliable and don't really want the added flow restriction of running a paddle-style flow meter 100% of the time.

I was thinking of trying to figure out a way to plumb a union where I would want to install the Neptune Flo sensor when I need it. Then, once I've got the readings I want, I remove the flow sensor and install 1" pipe back in its spot. This would be pretty easy if I could figure out who Neptune OEM's their unions from and I could just buy 12 extra ones.

Alternatively, I've been looking at other ways this is solved in industrial solutions and they have "plug-in" style flow meters that require a special fitting to be pre-installed in the plumbing. It would be cool to invest in one really nice industrial-grade flow meter (even if one was around $500) and just plug the fittings when I don't need to do any test. I would produce some additional friction in the line from the plugged fitting, but I would still feel better than the Neptune sensor and would know it was 100% accurate.

I also thought about investing in a GHL just to use their flow sensors. The GHL sensors about 2x the price of the Neptune sensor, but they are either electromagnetic or ultrasonic and have no moving parts in them like the Neptune flow probes have. My total investment cost in this option would probably be similar to the industrial solution that I mentioned above and I get the added benefit of being able to play around with GHL and Apex on the same system ;-)

Anyways, I welcome any ideas and comments on the topic.

 

[rsumner]

I thought about some more this afternoon and I think I came up with a solution to where I can purchase one 1" flow sensor (most are BSPT) and make 6 assemblies that will live permanently. The flow sensor could be one from Neptune or there are some with built-in LCD's for standalone measurements. Then, all I have to do when I want to measure the flow of a particular segment of pipe is:

1. shutdown pump (or cutoff flow with ball valve)
2. remove the "permanent assembly"
3. install the "flow sensor assembly"
4. turn on pump (or open ball valve)
5. take measurement

Here's a drawing to show what I mean:

FlexPVC.com carries the BSPT to Slip 1" Female adapter.

 

[rsumner]

Thinking about this a little more: Issue with my idea is that every ”permanent assembly” will need to be the same length otherwise the “flow sensor assembly” won’t swap out evenly. Hrmmm.

 

[rsumner]

I found a great write up for anyone interested in learning about the different type of flow meters:

3.5: Flow Sensors

Flow measurement proves crucial in various industries including petroleum and chemical industries. Consequently, flow measurement becomes a major component in the overall economic success or failure …

eng.libretexts.org

It would seem that paddle wheel sensors are less prone to temp or ionic changes in the water over ultrasonic ones. Hrmm. Interesting.

I may give up and just buy 6 Neptune probes

 

[n2585722]

Thinking about this a little more: Issue with my idea is that every ”permanent assembly” will need to be the same length otherwise the “flow sensor assembly” won’t swap out evenly. Hrmmm.

You can always add some clear flexable tubing in just in case there is a difference. I cut my PVC on a table saw a do them all at the same time so I can get them the same length if needed. So it can be done.

 

[nbooks]

what controller (if any) are you using?

hydros can interface with Gredia flow sensors off amazon, i just bought two 1" sensors for $18. yes you would have to make all the sections same length, but the sensors are actually quite short...and i even got lazy and used npt unions on bspt sensors...just seal with some silicone paste and a dab of bathroom silicone lol. ill try to remember to post a pick of my UV line setup tonight

Interfacing Gredia flow sensors to the Hydros

I have been asked several times about how to interface the Gredia flow sensors that can be purchased on Amazon (located here). I have had 3 of these sensors in operation on the Hydros for about 2 months. I have a 1.5" model on my return pump and I have 2 of the 0.5" models on my reactors...

forum.coralvuehydros.com

 

[rsumner]

what controller (if any) are you using? hydros can interface with Gredia flow sensors off amazon,

I use an Apex for my controller/automation, but thanks for the link to info on the Hydros. I had no idea the Hydros was more flexible in handling DIY sensors than the Apex. I don't mind a little soldering

I'm still deciding if I want to try to design my plumbing for temporary installation of flow meters or permanent ones. I'm very picky and OCD about my plumbing design.

 

[nbooks]

I went down the thought path your on as well. Back and forth and back and forth on whether or not to put flow sensors in my returns (im FOWLR at the moment so i have zero power heads with dual 1.25" returns providing all flow).

I eventually convinced myself to pass on it mainly because i was still thinking apex at the time (had some sensors that came with the used setup tank setup i bought)...now i kind of regret not doing it honestly.

 

[rsumner]

I haven't been able to find official published numbers on how accurate the Neptune flow sensors are, but considering their price point, they are probably +-10%. Most reefers probably wouldn't care about their sensor being 10% off, but I do.

The biggest problem that I'm finding is that flow meters with a +-1% accuracy are around $600. Grrr!!!

 

[rsumner]

My plumbing is definitely more complicated than most reefers are challenged with. I have 3 pumps, 4 UV's, external skimmer, chiller, and 5 1" return lines. I've decided I'm going to plumb everything with unionized segments (shown above in my drawing) to accept the Neptune flow sensors day 1. When I start getting frustrated with them, I'll pull them out and replace the segment with straight pipe. I'm going to scrap (and sell) the Neptune BSPT unions and replace them with BSPT adapters and standard Spears unions. I don't want to create a long-term dependency on the unions that are included with the Neptune flow meters.

I may still invest in a high quality flow meter to play with later down the road, but I've got too many other problems to solve with my build right now.

Thanks for all the feedback everyone.