HHP's 10K HPA Build Thread!

indrhrvest

New Member
Makes no odds to me, but i`m sure potential customers would appreciate having the option of tighter mist control, that translates to lower water/nute consumption as well as lower maintenance.
Pump based HPA (aka TAG) is very dated, it was knocking around on Overgrow at least a decade ago. If you offer the more modern, accumulator driven system it may give you an advantage over competitors that are using pumps.
Most advances in modern aero have come from growers on forums just like this one, it doesnt look like thats going to change anytime soon.
Even with our smaller accumulators, our system isn't TAG. The double 24 oz accumulators will run 2-3 cycles before the pump must recharge the system. Total water volume through the pump will never change whether you use a large accumulator and tandem pump, or numerous smaller accumulators and pumps. So even though a large accumulator and tandem pump setup will decrease overall costs, those two pumps would now be responsible for handling the entire volume transfer that could be spread out over numerous pumps. Total pump cycles wouldn't change so having numerous pumps may cost more, but it would reduce risk of failure by spreading pump cycles out over the entire system.
 

Atomizer

Well-Known Member
TAG may actually be slightly more consistant given that those 2-3 misting cycles will be at ever diminishing tank pressures, (hi, mid, lo), between your pump runs ;).
Fitting a pressure reducer to a large accumulator is both cost effective and beneficial to consistant mist performance (flowrate, droplet size, pattern etc), you`ll notice most if not all of the accumulator driven HPA`s on RIU are using one for that very reason ;)
Fitting a reducer to each 24oz tank probably wouldnt be worthwhile just for 3 cycles. I`m surprised you didnt catch this in the R&D phase.
 

indrhrvest

New Member
I`m surprised you didnt catch this in the R&D phase.
We never saw pressure drops below 50 psi and most the time it was around 60 PSI with the solenoid open, so there wasn't anything to catch. Our accumulators are set at 85PSI, our pumps are set at 70PSI. We aren't trying for perfect mist quality, we are simply trying to achieve a happy medium. If we maintain above 50 PSI, which we are then I'm satisfied. That gives us the mist we are looking for. We do run a slightly wetter mist to mitigate risks.

As for mist quality, whether your pressure is a constant pre-solenoid, you still get pressure drop in the nozzle manifold once the solenoid closes. So you are going to go from 55 micron down to around 80 in the chamber anyway. In a small hobby system you can control the mist quality, in a large system like ours, it's going to be impossible given the long runs and line volume post solenoid.
 

Atomizer

Well-Known Member
As for mist quality, whether your pressure is a constant pre-solenoid, you still get pressure drop in the nozzle manifold once the solenoid closes. So you are going to go from 55 micron down to around 80 in the chamber anyway. In a small hobby system you can control the mist quality, in a large system like ours, it's going to be impossible given the long runs and line volume post solenoid.
Mist quality and tight control with long runs is perfectly possible. Check out the vid 15 seconds in, there`s at least 60 misting nozzles on the single pipe run and it still manages a 1 second response. Mist quality has little to do with the system size, its all in the design and hardware choice.
[video=youtube;y6KjH9iNp3Q]http://www.youtube.com/watch?v=y6KjH9iNp3Q[/video]
 

indrhrvest

New Member
Mist quality and tight control with long runs is perfectly possible.
Are you suggesting that as the line pressure drops, post solenoid closing, that you are maintaining "tight control" of the atomization? I promise, that no matter how stable you keep your pressure pre-solenoid, that once the solenoid closes, your atomization goes from 50 microns on the low side, to 80+ on the high as the pressure drops regardless of the initial burst.. So your chamber, in an HPA configuration, will never finish with the micron pattern it started with.

Also, in terms of initial burst pressure, if you have your demand switch set at 80PSI, the initial push into the static manifold will always be at least 80 PSI. During a 3 second feed time, you may see a drop to 60 PSI depending on where the pressure was and how quickly the pump picks it back up..

But in the end.. it doesn't matter. Whatever your initial pressure post solenoid is, once that solenoid closes, your line pressure will drop from it's peak down to zero and as it does, your mist pattern and atomization changes. Unless you have a solenoid right at the nozzle, the longer the run, the more the variation of the mist quality is as the volume is dispersed through the nozzles. More volume simply means a slower drop in pressure.

I get the impression you think we are starting with a lower pressure because we use a smaller accumulator. We will always start with at least 80PSI, because that's where the demand switch is set. Obviously if we start off at 100PSI, the accumulator may loose some pressure but not enough to kick the pump back on. That's why we go 2-3 cycles without the pump cycling.

It just seems ridiculous to strive for a certain initial pressure, when your finishing pressure will always be peak.. to zero. Thereby, no matter how hard you try, you will always have a higher micron figure hitting the plants. The only way to solve that is put a solenoid at every nozzle. That might be easy if your filling a shoebox with one nozzle.. but we are filling 32-64 cubic feet.
 

Atomizer

Well-Known Member
Here`s a 5m long, 56 cubic foot "shoebox" that manages 1 second or shorter mist pulses. Its insulated and didnt cost much but it delivers mist quality and response like the earlier video. The line pressure after the solenoids never drops to zero so the mist quality doesnt suffer and more importantly no nutes arent wasted at the end of each misting pulse. The instant response means its not limited to some minimum misting duration (eg 3 seconds) to ensure all the nozzles start misting, which also reduces unnecessary waste. If 3 seconds is the system minimum, thats the minimum you can use, its much better to design for 1 second or less so you have the choice. Imho, these kind of performance limitations will leave you open to any competitor that employs a different approach as they can offer better performance, less waste at a lower cost.

outdoor chamber.jpg
 

indrhrvest

New Member
The line pressure after the solenoids never drops to zero so the mist quality doesnt suffer and more importantly no nutes arent wasted at the end of each misting pulse.
How exactly are you able to achieve zero pressure drop post solenoid closure? I have yet to find any nozzles that can magically turn themselves off in tandem with a primary valve closure to maintain line pressure. If they do exist, I'd imagine they would be quite expensive. Solenoid open and close times, up to a point, won't make a huge difference on total volume dispersed through a nozzle. For example, an 8 foot run (3/8) with say 7 nozzles, will most likely fully pressurize when using a 1 second open time. However, the mist will run longer than 1 second due to the volume/pressure. Pressure is simply the energy that forces the volume through the nozzle. What comes out of the nozzle is dictated by both volume and pressure. I haven't done any testing to determine the pressure at which a Tefen nozzle no longer provides an atomized mist, however that is something I may try since I have a video camera capable of doing 240fps in HD. The point I'm making is whether one uses a 1 second, or 3 second open cycle, what truly dictates the mist cycle is the number of nozzles, thier flow rate and the volume/pressure within the line. It's quite possible that the difference between a 1 second and 2 second open time could be very minimal depending on the total flow rate of the nozzles. When it comes to mist quality though, you'll never achieve 100% micron consitency because as the volume is dispersed, pressure drops, thereby changing the pattern and micron size regardless of solenoid open time.

Also, going back to pump failures. We've been working with Shurflo on our final pump specs for private labeling purposes. I brought up relaiblity with Shurflo based on our system operation. Our pumps utilize a bypass, so even if the switch fails according to Shurflo, the worst thing that would happen is the pump would just run constantly in bypass mode, but the system would continue to function properly. So being alerted to a failed pump, would simply be a matter of catching it on a daily walk through. The chance of the switch failing closed is rare according to Shurflo. I was also told diaphram life would be longer using our short cycle vs a longer cycle.
 

Atomizer

Well-Known Member
The mainline in the vid has to be a good 75-90ft of 3/4" tube. If the pressure was ramping up and down from zero, there`s no way they`d get close to a 1 second misting pulse, it`d be more like 5-10 seconds. You`d also be seeing a defined wave of mist running the length of the line as each nozzle would rob pressure and flow creating a delay for the next nozzle down the line. Its visible in your misting vids with the old chunky manifold, the nozzles nearest the pumps start first and finish last, they seem to spit a bit before they start misting too ;)
 

indrhrvest

New Member
The mainline in the vid has to be a good 75-90ft of 3/4" tube. If the pressure was ramping up and down from zero, there`s no way they`d get close to a 1 second misting pulse, it`d be more like 5-10 seconds.
Look at how much water those nozzles put out.. you can't compare the Tefen nozzles we are using to the nozzles in those videos. You really can't seriouly make a comparrision here. You are comparing a bridgeless, 100 micron nozzle head that flows 25 l/h to a tiny little low tech Teffen nozzle. I'm also quite sure if you zoomed in and did a 240 FPS video, those nozzles would "spit" too. Obviously flowing 100+ micron at 25 l/h your not going to see any spitting.. Each one of those quad nozzle heads is pushing 100 l/h.

Let's see a slow motion video of your setup, then we can actually compare something. Here's a real time video and slow motion video using a 1/2 manifold.

http://www.youtube.com/watch?v=SGNo95f4dI4

http://www.youtube.com/watch?v=w_6t1kevAMs
 

Atomizer

Well-Known Member
Each one of those quad nozzle heads is pushing 100 l/h.
The grey quads push 30LPH, (7.5LPH x 4 ), they dont begin misting until they are at a minimum pressure of 58psi.
That nozzle in your 2nd vid reminds me of Old Faithful, it`d be interesting to measure the percentage of nutes that run to waste before mist starts.
Not a great quality vid but good enough to demonstrate an instant start/stop response. Listen for the solenoid for an idea of the timing.
[video=youtube_share;_Md6yoPvoMU]http://youtu.be/_Md6yoPvoMU[/video]
 

Atomizer

Well-Known Member
If you want really short misting durations you cant beat the response of AA. The lower limit is pretty much set by the solenoid response time. This pulse is very short (listen to the solenoid) but still delivers enough mist to fill a 20gal chamber.
[video=youtube_share;DE7xIlU3vf0]http://youtu.be/DE7xIlU3vf0[/video]
 

oxanaca

Well-Known Member
If you want really short misting durations you cant beat the response of AA. The lower limit is pretty much set by the solenoid response time. This pulse is very short (listen to the solenoid) but still delivers enough mist to fill a 20gal chamber.
[video=youtube_share;DE7xIlU3vf0]http://youtu.be/DE7xIlU3vf0[/video]
is this a flat fan. i tryed to stop it to see the mist pattern but its just too fast
 

indrhrvest

New Member
The grey quads push 30LPH, (7.5LPH x 4 ), they dont begin misting until they are at a minimum pressure of 58psi.
That nozzle in your 2nd vid reminds me of Old Faithful, it`d be interesting to measure the percentage of nutes that run to waste before mist starts.
Yes, I'm aware they are more controlled, they are bridged nozzles. They also cost considerably more, far more in CAPEX than I would waste with a little extra run off. We are trying to run a profitable business, not worry about minute details that really have no effect on the final production quality.
 

oxanaca

Well-Known Member
The grey quads push 30LPH, (7.5LPH x 4 ), they dont begin misting until they are at a minimum pressure of 58psi.
That nozzle in your 2nd vid reminds me of Old Faithful, it`d be interesting to measure the percentage of nutes that run to waste before mist starts.
Not a great quality vid but good enough to demonstrate an instant start/stop response. Listen for the solenoid for an idea of the timing.
[video=youtube_share;_Md6yoPvoMU]http://youtu.be/_Md6yoPvoMU[/video]
a quad of the purple or (light green in the USA) would only be 22 liters per hour.

hey indoor if you check these nozzle out could you let me in on where you get them from i live in the united states an am having a hard time finding a supplyer that sells the 5.5liter nozzles by the box. i cant even find them retail. theres only 2 website that sell netafim quads and them only stock them with the 7.5liter quads. good prices though $5.50 for the quad with the check valve.
 

indrhrvest

New Member
hey indoor if you check these nozzle out could you let me in on where you get them from i live in the united states an am having a hard time finding a supplyer that sells the 5.5liter nozzles by the box. i cant even find them retail. theres only 2 website that sell netafim quads and them only stock them with the 7.5liter quads. good prices though $5.50 for the quad with the check valve.
It wouldn't be a nozzle we'd be interested in, so I haven't really looked at them. We can get Tefens at $0.60 a pop from the manufacturer. In the bigger picture, the Tefen's would have more run off, but a few extra gallons a day at $.005 per gallon doesn't justify the extra cost of these fancy nozzles. Sure they are cool.. but the plants aren't really going to know the difference.
 

oxanaca

Well-Known Member
It wouldn't be a nozzle we'd be interested in, so I haven't really looked at them. We can get Tefens at $0.60 a pop from the manufacturer. In the bigger picture, the Tefen's would have more run off, but a few extra gallons a day at $.005 per gallon doesn't justify the extra cost of these fancy nozzles. Sure they are cool.. but the plants aren't really going to know the difference.
it really only costs you half a penny to make a gallon of nutrient solution? thats impressive what EC is this at? i mix my own nutes with chemicals i bought in 50# bags and im pretty sure im paying more than that.
 

indrhrvest

New Member
it really only costs you half a penny to make a gallon of nutrient solution? thats impressive what EC is this at? i mix my own nutes with chemicals i bought in 50# bags and im pretty sure im paying more than that.
I was being sarcastic.. point is, we are not really wasting all that much water or nutrients compared to what's commercially available. We know from talking to several hydroponic growers, they are using anywhere from 4-7 gallons per head of lettuce. We are doing them in under 3 gallons drain to waste and 15 days quicker with our prototype. I'm more than satisfied with that result considering the changes we've made.

With our new 3/8 manifolds, that's going to drop water usage down considerably over the 1/2 lines. There is a very small hole drilled in the 3/8's where the bung is welded. The "spitting" and excessive water usage was from our prototype 1/2 pvc manifolds. They were never intended for final production. We've been doing R&D for a reason...

 

indrhrvest

New Member
Just out of interest what does the stainless manifold cost? $300-$400?
For a 110 plant site manifold (8 runners supporting 60 nozzles), it would be about $1,300 and come with a lifetime warranty. Not everyone is going to want a stainless manifold obviously. It's an option for commercial applications.
 
Top