high pressure aero diy skid...need help with electrical

so let me first start out by saying big respect to r0m30, trichy bastard, cavadage, and many others for helping me out with this

the box is a panel control box for a 2 gallon accumulator HPA system im working on....i got most of the specs from the guys i mentioned and wanted to lay it all out and build a nice container for it...i have limited space so and i wanted to make something that would at least appear to be built to last a while

the idea is the pump sucks water and nutes from a 5 gallon bucket, through a filter, and pumps it to about 100 psi...it goes through a pressure switch and tees into the accumulator and the solenoid path..there is a regulator before the solenoid....the solenoid is hooked up to the timer...there is a safety nozzle on the accumulator path

there are pressure gauges before and after the pump and after the solenoid valve

the actual plumbing will be npt x john guest and john guest fittings with 1/4" poly (shown in blue)...there is a hodge podge of fittings used to connect the tank...in reality i will not use any elbows, i had to cuz my cad program can be a bitch with sweeps

i want to include a kill switch (on/off) and the fan on/off...but my wiring skills are null and void....i know the valve has a 12 VDC to the timer...im assuming the valve gets it power from the timer too...the timer gets powered to a wiring juction box thingy...the pump gets wired to the wiring juction box thingy for power too...the pressure switch just gets wired to the pump, right? idk...its going to take me a month just to figure out the electrical so if anyone can help please chime in

i have the specs on everything in the assembly, including prices and sources if anyone is interested

thanks,
BD

i havent built one yet. post your parts list.
i gathered rohms list and priced it out.

my general parts list below

ITEM; SOURCE; PART NUMBER; PRICE; NOTES

the items used not shown are various npt fittings from either grainger or mcmaster and the john guest fittings i will get from freshwastersystems.com

i went with the asco solenoid because i dont trust the plastic ones from ebay

any questions n let me know, ill be more than happy to answer them

i still need to know how to wire this all together!!



FILTER; FRESHEWATERSYSTEMS.COM; 158114; $13.89; 30 MICRON CARTRIDGE

PRESSURE GAUGE; GRAINGER; 5WH20; $13.64; 0-30 PSI

PUMP; WATERFILTERSOURCE.COM; 6841-4J03-B221; $99.99; AQUA TEC 6800 SERIES

DP SWITCH; WATERFILTERSOURCE.COM; PSW-240; $15; 30-60 PSI RANGE, 40 PSI ON

PRESSURE RELIEF VALVE; GRAINGER; 6D915; $7.49; ADJUSTABLE W 4 SPRINGS

ACCUMULATOR TANK; FRESHWATERSYSTEMS.COM; ST-5PL; $39.99; WILL MOST LIKELY GO TO HD

PRESSURE GAUGE; GRAINGER; 5WH23; $13.64; 0-200 PSI

PRESSURE REGULATOR; GRAINGER; 1DMK5; $47.60; 0-125 PSI REGULATION

RECYCLE TIMER; ISEINCSTORE.COM; 422A100F10X; $106; INCLUDES PANEL MOUNTING KIT AND SOCKET

SOLENOID VALVE; GRAINGER; 4EKX5 (ASCO 8262G022); $53.60; 12 VDC GEN PURPOSE ASCO

below is the flow diagram..again, big respect to r0m30 for the help

whats shown in the box is what is in or attached to the wooden box

BD

Wow, props on the sketchup, very nice!

boodadood said:

there are pressure gauges before and after the pump and after the solenoid valve

Click to expand...

Not sure you need a pressure gauge before the pump, it's suction driven you could save a few bucks there.

boodadood said:

the actual plumbing will be npt x john guest and john guest fittings with 1/4" poly (shown in blue)...there is a hodge podge of fittings used to connect the tank...in reality i will not use any elbows, i had to cuz my cad program can be a bitch with sweeps

Click to expand...

Glad to see those elbows are not in the plan.

It's a little hard to tell but it looks like you have the pressure switch hooked up to the inlet and outlet sides of the pump in the diagram. It should only be hooked up to the outlet side. then the output from the pressure switch should be tee'd to the accumulator and the pressure regulator.

boodadood said:

i know the valve has a 12 VDC to the timer

Click to expand...

12V is a good choice for safety but not required. If you chose a voltage that works best with the rest of your power needs you can reduce the number of different voltages required simplifying your setup.

boodadood said:

im assuming the valve gets it power from the timer too

Click to expand...

I'm not familiar with this timer but .....
No, the timer is basically a relay that switches on and off at the specified intervals. If you download the literature for the timer you selected in the typical applications diagrams you will see a line called independent load line, that's your solenoid power line, and it's not supplied by the timer.

boodadood said:

the timer gets powered to a wiring juction box thingy...the pump gets wired to the wiring juction box thingy for power too...the pressure switch just gets wired to the pump, right?

Click to expand...

Yes, sort of, sort of. The specs on the timer say it can be powered by 24VAC so you should be able to power it off of the aquatec power supply. The pump power is supplied (and controlled) by the pressure switch. If you use an aquatec pressure switch they either come with the wiring harness or you can order it as an option depending on who you order it from.

boodadood said:

idk...its going to take me a month just to figure out the electrical so if anyone can help please chime in

Click to expand...

Hope this helped, if not I'll try again

boodadood said:

i have the specs on everything in the assembly, including prices and sources if anyone is interested

Click to expand...

It would help to know exactly what parts you're planning on using when trying to help with the plumbing and/or wiring.

ilikecheetoes said:

i havent built one yet. post your parts list.
i gathered rohms list and priced it out.

Click to expand...

There is an ebay seller called hwl999 that sells the 6800 with power supply for $85 including priority mail shipping.

boodadood said:

my general parts list below

ITEM; SOURCE; PART NUMBER; PRICE; NOTES

the items used not shown are various npt fittings from either grainger or mcmaster and the john guest fittings i will get from freshwastersystems.com

i went with the asco solenoid because i dont trust the plastic ones from ebay

any questions n let me know, ill be more than happy to answer them

i still need to know how to wire this all together!!



FILTER; FRESHEWATERSYSTEMS.COM; 158114; $13.89; 30 MICRON CARTRIDGE

PRESSURE GAUGE; GRAINGER; 5WH20; $13.64; 0-30 PSI

PUMP; WATERFILTERSOURCE.COM; 6841-4J03-B221; $99.99; AQUA TEC 6800 SERIES

DP SWITCH; WATERFILTERSOURCE.COM; PSW-240; $15; 30-60 PSI RANGE, 40 PSI ON

PRESSURE RELIEF VALVE; GRAINGER; 6D915; $7.49; ADJUSTABLE W 4 SPRINGS

ACCUMULATOR TANK; FRESHWATERSYSTEMS.COM; ST-5PL; $39.99; WILL MOST LIKELY GO TO HD

PRESSURE GAUGE; GRAINGER; 5WH23; $13.64; 0-200 PSI

PRESSURE REGULATOR; GRAINGER; 1DMK5; $47.60; 0-125 PSI REGULATION

RECYCLE TIMER; ISEINCSTORE.COM; 422A100F10X; $106; INCLUDES PANEL MOUNTING KIT AND SOCKET

SOLENOID VALVE; GRAINGER; 4EKX5 (ASCO 8262G022); $53.60; 12 VDC GEN PURPOSE ASCO

Click to expand...

You said in the first post you were shooting for around 100PSI, the PSW240 has a maximum cutout pressure of 80 PSI, the PSW260 has a max of 110 and the PSW280 has a max of 130.

Your solenoid is brass, plastic or stainless steel would be better with all the salts in the nutrient solution.

You might post a request for feedback on Trichey's thread to get some more input.

thanks bro...follow up with you on a couple things here

i put a pressure gauge before the pump for a couple of reasons...i wanted to keep an eye on the supply pressure to the pump to not have it run dry...and i thought it might help figuring out when it is time to change the filter...i now know the diaphram pumps can run dry...but would you see the value of monitoring this pressure for either the filter replacement or even general pump performance to note wear on the pump?

so if i put a 5 gallon bucket res on the floor next to the cab, and run a tube from the filter down into the bucket and turn the pump on, the pump will suck up from the bucket? or do i need to keep the res higher than the pump to flood the pump? i know with centrifugal pumps you need to make sure there is positive suction on the supply side of the pump...idk too much about diaphragm pumps

yeah the elbows are there just for modelling...and the pump is fed like the flow diagram...in the image its tricky to see but the other tube that looks like its coming out of the top of the pump is after the pump, after the switch, on the way to the tank

for the solenoid...i didnt want to use the plastic ebay ones because they look cheap...and i know brass is horrible with other metals...but i wanted a decent valve n stainless is too much...im prolly gonna go with the plastic ebay ones and just pick up 2 or 3 of them...there are some other brass fittings in the model as well...like coming off the tank and the plugs for the regulator...these were already available in the CAD library so i used them...in reality i would use either a plastic or a stainless fitting...there may be a way i can score a boatload of stainless compression fittings from work...swagelok style....if i do that, i might just do the whole thing in stainless, including tubes...if i save all that money on the JG stuff, id just blow it on the rest of the stainless i would need

if the timer is 24V and the pump is 24V, does that mean i should get a 24VDC solenoid and run everything off the pressure switch?

that means i would supply main power to the pressure switch, and when i turn it on, then the valve, the pump, and the timer will all go on (or be energized)? in that case i just need to wire up the dp switch with the harness and 120V to plug into the wall? im really bad at this stuff...

back to the regulator a minute...the spec sheet says there is one high pressure inlet port...and im left to figure out that the other 3 ports are the low pressure outlet ports? or is only the port inline with the high pressure port the low pressure output port? im assuming you have to use their noted high pressure port, and then you can use any or all of the 3 other ports, or a combination of the 3...is this correct?

thanks for the heads up on the psw240....is there a better, perhaps more reliable aftermarket switch that you know of that would work well in the system? or should i save the headache and go with the aquatec supplied psw switches for the ease of setting shat up?

thanks again bro

BD

boodadood said:

thanks bro...follow up with you on a couple things here

i put a pressure gauge before the pump for a couple of reasons...i wanted to keep an eye on the supply pressure to the pump to not have it run dry...and i thought it might help figuring out when it is time to change the filter...i now know the diaphram pumps can run dry...but would you see the value of monitoring this pressure for either the filter replacement or even general pump performance to note wear on the pump?

Click to expand...

I don't know if it would help with the filter changes or not, the output pressure should tell you if the pump is wearing out.

boodadood said:

so if i put a 5 gallon bucket res on the floor next to the cab, and run a tube from the filter down into the bucket and turn the pump on, the pump will suck up from the bucket? or do i need to keep the res higher than the pump to flood the pump? i know with centrifugal pumps you need to make sure there is positive suction on the supply side of the pump...idk too much about diaphragm pumps

Click to expand...

The 6800 is rated to self prime to 7 feet, in reality it takes forever with the back pressure from the CV in the mist heads. What I do is open up the pressure release ball valve and route that back into the res then turn on the pump and let it prime. Once the pump is primed I haven't had issues with it losing prime but cloner res is only a few inches below the pump head and my flower res is above the pump.

boodadood said:

for the solenoid...i didnt want to use the plastic ebay ones because they look cheap...and i know brass is horrible with other metals...but i wanted a decent valve n stainless is too much...im prolly gonna go with the plastic ebay ones and just pick up 2 or 3 of them...

Click to expand...

These are stainless and less than the brass one you spec'd. I think TB has another source for stainless valves as well.

boodadood said:

if the timer is 24V and the pump is 24V, does that mean i should get a 24VDC solenoid and run everything off the pressure switch?

that means i would supply main power to the pressure switch, and when i turn it on, then the valve, the pump, and the timer will all go on (or be energized)? in that case i just need to wire up the dp switch with the harness and 120V to plug into the wall? im really bad at this stuff...

Click to expand...

First the pump is 24V AC not DC that's important if you don't want to be replacing stuff when you wire this up..... The timer is multi voltage so you have a lot of options there.

You could go with a 24 VAC solenoid or if you are going to be using PC fans for circulation a 12VDC would work. I only wanted to be clear that 12VDC in not required.

You keep wanting the pressure switch to control everything, get that out of your head it only controls the pump.

I can't get to the site you listed for the pump, is that with or without the power supply? you can't hook the aquatec pump or the aquatec DP switches to 120 directly you need a 24 VAC power supply.

Here's how an all 24VAC system would work:

24VAC power supply plugs into the wall, three pairs of wires would be split off of the power supply.
The first pair would go to the DP switch, the wiring harness would power the pump when the pressure falls below the cut in pressure.
The second pair would go to the timer for it's power.
the third pair would be routed thru the timer (the independent load line from above) to the solenoid.

boodadood said:

back to the regulator a minute...the spec sheet says there is one high pressure inlet port...and im left to figure out that the other 3 ports are the low pressure outlet ports? or is only the port inline with the high pressure port the low pressure output port? im assuming you have to use their noted high pressure port, and then you can use any or all of the 3 other ports, or a combination of the 3...is this correct?

Click to expand...

The one I bought was the two port model you'd have to read the spec sheet on the multiport models to determine which port to use.

boodadood said:

thanks for the heads up on the psw240....is there a better, perhaps more reliable aftermarket switch that you know of that would work well in the system? or should i save the headache and go with the aquatec supplied psw switches for the ease of setting shat up?

Click to expand...

Given your self proclaimed lack of electrical knowledge I think going with the PSW280 and the prebuilt wiring harness would be easiest. I don't know how they will hold up in a HP Aero setup but I'm going to find out......

Hey man i really appreciate you gettin back to me on all this stuff...i can wait to get the ball rolling and start ordering some things..its going to take me about 2 months to grab everything i need for the setup and i have a whole other grow already goin..lol...i wanna get shit in tho so i can start settin it up and tinker with it

i went over all your good stuff and went thru trichy's thread again...theres some good shit in that and i was able to find some more suitable products

below is the updated list....i decided to not deal with freshwatersystems.com as the rep is sorta 50/50 and went to dultmeier and a few others

the stainless stc solenoids look kick ass and im thinking about getting one for each root chamber to limit the tube lengths from the valve to each plant

i also went with 24v on everything...i barely know enough about that stuff as it is and i figured why mess around...im still on the fence about which switch to use tho

i kept the suction side pressure gauge on there just to have another needle to look at bouncing around...even if it serves no other purpose

im going to put together a wiring diagram n layout the way i see the electrical connections...i want to include a master shut off switch, the fan switch, and a touch screen control panel that will...im just kidding about the touch screen...but i may add a couple of more features

i need to learn about this stuff...ive been meaning to for a while now for other reasons so this will help with my hobby and my job too

i cant find the diagram youre talking about that notes the load line of the timer...i have the spec sheet from atc too...idk, im going to do alot more research into the wiring situation and take a real good look at it

once i come up with a really bad wiring sketchup ill post it and hopefully you could give it a once over...im gonna hit up trichy too n see if he can offer any insight

rock on bro n thanks again for all your help

BD


FILTER HOUSEFILTERSYSTEMS.COM PENTEK 158138 $11.16 5" HOUSING; 1/4" FNPT

FILTER CARTRIDGES HOUSEFILTERSYSTEMS.COM R30-478 $17.98 30 MICRON CARTRIDGE X 2

REPLACEMENT O RING HOUSEFILTERSYSTEMS.COM OR-38 $5.99 3.5" DIAMETER

MOUNTING BRACKET HOUSEFILTERSYSTEMS.COM SL-BR $5.99 FOR SLIMLINE FILTERS

PRESSURE GAUGE GRAINGER 5WH20 $13.64 0-30 PSI; 1/4" MNPT

PRV FITTING FOR MALE END GRAINGER 1LTP2 $5.22 REDUCING COUPLING 1/2 X 1/4 FNPT; STAINLESS

PRV FITTING FOR FEMALE END GRAINGER 1LUN2 $3.64 HEX REDUCING BUSHING 1/2 MNPT X 1/4 FNPT; STAINLESS

TANK FITTING GRAINGER 1LUN6 $5.49 HEX REDUCING BUSHING 3/4 MNPT X 1/4 FNPT; STAINLESS

PRESSURE GAUGE S GRAINGER 5WH23 $27.28 0-200 PSI X 2

PRESSURE REGULATOR GRAINGER 1DMK5 $47.60 0-125 PSI REGULATION

RECYCLE TIMER ISEINCSTORE.COM 422A100F10X $106.00 INLCUDES PANEL MOUNTING KIT AND SOCKET

DP SWITCH DWER CXA-S3 $18.00 35-150 range; 30-40 adj deadband; NC

PRESSURE RELIEF VALVE EBAY 350397357443 $16.50 1/2" PRESSURE RELIEF 75-150 PSI

ACCUMULATOR TANK PEXSUPPLY.COM 140735 SKU $32.95 2 gal, 150 psi max; 3/4" FNPT

PUMP PUREWATERPRODUCTS.COM RP001, RP008 $122.00 AQUA TEC 6800 SERIES; 40-120 BOOST; 1/4"; MODEL 6840-2?03-B221; INCLUDES TRANSFORMER; FREE SHIPPING

SOLENOID VALVE STCVALVE.COM 2S025+2 $32.22 2 WAY NC 1/4" NPT 150 PSI MAX STAINLESS STEEL 24 VDC

MALE ADAPTER FITTING DULTMEIER.COM LM MC1414 $13.56 JG MALE ADAPTER 1/4 TUBE X 1/4 NPTF MALE X 12

TEE FITTINGS DULTMEIER.COM LMTC14 $8.84 JG UNION TEE 1/4 X 4

FEMALE ADAPTER FITTING DULTMEIER.COM LMFC1414 $7.23 JG FEMALE ADAPTER 1/4 TUBE X 1/4 NPTF X 3

boodadood said:

i cant find the diagram youre talking about that notes the load line of the timer...

once i come up with a really bad wiring sketchup ill post it and hopefully you could give it a once over...im gonna hit up trichy too n see if he can offer any insight

Click to expand...

That's because I was looking at the wrong timer on their site, sorry.

Good luck, I'll be happy to help as much as I can....

so i did some reading and followed the trail of bread crumbs you put down...the 422 timer is a 2 pole, 8 pin relay...i found a diagram that explained how to wire it up and what the layout of the terminal numbers are...in the "timer wiring" i note what is on the spec sheet, how i interpreted the connections, and how i think it should be wired based on your description and some other stuff i found...one of the two poles is not used because i only use one valve

which leads me to another question i have...couldnt you use a tee and have one line going to the misters and one line going back to the res?

there would be 2 valves, one NC solenoid set on the mister supply line and another N0 solenoid set on the line back to the res...you put the nc valve on one pole of the timer set in the nc positions and the n.o. valve on the other set of contacts on the timer, arranged in the n.o. positions, and leave the pump running constantly and get rid of the accumulator tank?

idk...i think there are other forms of hpa out there but idk if that would be one of them, i havent looked into it much

anyway, im going to go with the psw280 so i can just get the harness and not worry about the other switch..lol

i did include the toggle on/off switch tho...im looking at simple 2 pin switches that i would wire into the positive (power) line of wherever i wanna use em...its my understanding these type of simple switches do not get grounded...and a simple $5 switch from radio shack can handle either DC or AC loads at pretty high potentials...i think

im only going to go with the one solenoid for now too...this is my first crack at it but once i get comfortable i will probably add more and mount them right to the chamber lids

let me know what you think man as im feelin pretty good about it now..by george i think i got it finally..lol

BD

Damn firefox crashed and ate my reply, take two......

boodadood said:

the 422 timer is a 2 pole, 8 pin relay...i found a diagram that explained how to wire it up and what the layout of the terminal numbers are...in the "timer wiring" i note what is on the spec sheet, how i interpreted the connections, and how i think it should be wired based on your description and some other stuff i found...one of the two poles is not used because i only use one valve

Click to expand...

This is where I'd sit down with my DMM and figure out what each pin did. I don't think this is correct. At the very least you only want one pair of wires. Usually in a single pole setup you would wire the AC load (+ in your diagram) to the timer pins and the AC neutral (- in your diagram) would be wired straight to the solenoid. You could also wire neutral to the second pole.

boodadood said:

which leads me to another question i have...couldnt you use a tee and have one line going to the misters and one line going back to the res?

there would be 2 valves, one NC solenoid set on the mister supply line and another N0 solenoid set on the line back to the res...you put the nc valve on one pole of the timer set in the nc positions and the n.o. valve on the other set of contacts on the timer, arranged in the n.o. positions, and leave the pump running constantly and get rid of the accumulator tank?

idk...i think there are other forms of hpa out there but idk if that would be one of them, i havent looked into it much

Click to expand...

How would you maintain the pressure? An open line running back to the res would cause the pressure to drop. I don't know how a system setup like that would perform. A guess would be that it would perform similar to a system that cycled the pump.

boodadood said:

i did include the toggle on/off switch tho...im looking at simple 2 pin switches that i would wire into the positive (power) line of wherever i wanna use em...its my understanding these type of simple switches do not get grounded...and a simple $5 switch from radio shack can handle either DC or AC loads at pretty high potentials...i think

im only going to go with the one solenoid for now too...this is my first crack at it but once i get comfortable i will probably add more and mount them right to the chamber lids

Click to expand...

How many amps can that timer handle? You would need to take that and the max output of your power supply into account when adding solenoids.

The flow diagram is looking good, I put my pressure gauge between the pressure regulator and the solenoid but there is nothing saying that is "the" correct place to put it.

i think i hear what youre saying on the wiring...i dont have time tonight to sketch it out but basically the solenoid gets wired just like a switch does....the positive power goes in and out of the valve and the neutral ground stays with the circuit, back to the power supply...am i catching on?

looks like i need to take another swing at it but i can taste it

the pressure gauge location on the way to the misters is subjective...i had it before the valve as well at first but i figured at the end of the flow, its really about the pressure that the misters see...and the closer this gauge is to them the better....i think the pressure in the line anywhere between the switch and the valve is going to be relatively constant...in terms of the tank pressure...in other words any gauge in this path is just going to register the tank pressure...with very little differences due to the dynamic head of the system...so seeing what happens after the valve is important...thats the way i look at it anyway

in my notion of getting rid of the accumulator and using two valves, i wasnt thinking about pressure loss from the pump....the pump would be running continuously....the valves are just redirecting the pressure (and flow) from either back to the res (a few minutes) or to the misters ( a few tenths of a second). The flip/flop timer relay switch thingy, all things being ideal, would perform this way...wouldn't it? why would you lose pressure if the pump is constant? the trick would be perfect timing between the valves and with a flip flop relay, wouldnt that timing be integral to the same switch?

im not tryin to challenge the tank...the tank is awesome...the tank frikken rules cuz nothing beats constant pressure...and positive displacement pumps are certainly not a constant pressure pump like a rotary or centrifugal

anyway, gotta run bro but thanks again for your huge comments...its clear i have more wiring schemes to look at and figure out how to mesh it all together

ill keep posting progress

BD

boodadood said:

i think i hear what youre saying on the wiring...i dont have time tonight to sketch it out but basically the solenoid gets wired just like a switch does....the positive power goes in and out of the valve and the neutral ground stays with the circuit, back to the power supply...am i catching on?

Click to expand...

Yes, I think so. The timer is nothing more than an automated switch.

boodadood said:

looks like i need to take another swing at it but i can taste it

the pressure gauge location on the way to the misters is subjective...i had it before the valve as well at first but i figured at the end of the flow, its really about the pressure that the misters see...and the closer this gauge is to them the better....i think the pressure in the line anywhere between the switch and the valve is going to be relatively constant...in terms of the tank pressure...in other words any gauge in this path is just going to register the tank pressure...with very little differences due to the dynamic head of the system...so seeing what happens after the valve is important...thats the way i look at it anyway

Click to expand...

You have three pressure zones after the pump. The first is what I call "Unregulated pressure", it's the pressure that the accumulator is presently at. The second ("regulated pressure") is the pressure between the pressure regulator and the solenoid is should be relatively constant but the rapid open close sequence of the solenoid pushes it higher that the actual regulated pressure. The third is after the solenoid. It will be lower than the regulated pressure when the solenoid is closed. Even with check valves in the misters there is a pressure drop in this segment as the misters continue to spray water after the solenoid has closed until the CVs close.

boodadood said:

in my notion of getting rid of the accumulator and using two valves, i wasnt thinking about pressure loss from the pump....the pump would be running continuously....the valves are just redirecting the pressure (and flow) from either back to the res (a few minutes) or to the misters ( a few tenths of a second). The flip/flop timer relay switch thingy, all things being ideal, would perform this way...wouldn't it? why would you lose pressure if the pump is constant? the trick would be perfect timing between the valves and with a flip flop relay, wouldnt that timing be integral to the same switch?

im not tryin to challenge the tank...the tank is awesome...the tank frikken rules cuz nothing beats constant pressure...and positive displacement pumps are certainly not a constant pressure pump like a rotary or centrifugal

Click to expand...

The pressure in the system is created by forcing an amount of water into a limited volume of space, the more water the higher the pressure if the volume of space stays the same. When you route the flow back to the res you have changed the amount of space for the water to fill to near infinity. I suppose you could pressurize the res but then it just becomes the accumulator.

Hey boodadood. I was just quickly glancing at my thread before bed. I will go over your thread here in depth in the next few days. It seems r0m found his way here, and he has a pretty good understanding of things, matter of fact his system is up and running compared to mine as a pile of parts sitting in the living room floor waiting for me to get a few days off from work-lol... Keep reading/researching- with hp aero the devil is in the details... Talk soon.

not to beat a dead horse here but i really think it would be possible to do without an accumulator…you would take a hit on the performance of the system, cuz i think overall the tank would supply a better constant head to the misters than a pump would…but this is why I think it would be possible:

take a look at “flow sketch” below…its just a very simplified version of what Im proposing…a pump connected to a res with a decent amount of water in it…pushing water to two valves…one N.O. leading to the res, one N.C. leading to the misters

There are two modes that this can operate…the first mode would be when both valve are in their normal state, the N.O. valve is open and the N.C. valve is closed…when this is the case, gauge 1 would read very little pressure as there would be no pressure drop really in the line between the pump and the res…P3 would read a very similar number...almost zero depending on how far away the actual gauge is to the res… and P2 would read whatever the static line pressure is from the last time the line was used, close to zero if not zero as well…these low pressures are because there is zero gauge pressure in the line…without a pressure drop restriction in the line, besides the plumbing, the system curve is flat

The second mode would be when the NC valve is open and the NO valve is closed…when this happens, the pressure at P3 becomes zero, and the pressures at both P1 and P2 register a dynamic head equal to all the plumbing plus the valve, plus the pressure drop of the misters…the system curve is much higher and even tho the pump flow never changed, the pressures at P2 have gone from just about nothing to whatever you size your pump to

If you look at a generic pump curve for any typical diaphragm pump, it looks like the red line in the graph “pump and system curves”…the ideal diaphragm pump would have a constant flow rate for any given pressure output in its range

The pressure in any fluid circuit can be summarized with a system curve…the system curve can be measured at any given point in the system when the pump is on…generally speaking, the more water you put into the never changing physical volume space, the more head in the system, and the higher the pressure gets

The point at which the system curve and the pump curve intersects is the point at which the system operates…this is sometimes called the design point…anyway, without a variable frequency drive on the pump motor, the motor cannot change and the pump does not change….the only way to change the operating point is to change the system curve

when the mister valve is closed there is no gauge pressure, no other head besides the plumbing, and the system curve is flat…when the mister valve opens and the res valve closes, the system now has dynamic head due to the misters…the pressure goes up…the flow rate has barely changed but more head has been added and the total dynamic head increases the pressure

like I said, it would not perform as well as the tank because the pressure build up is not instantaneous or as constant as a bladder with a fixed orifice deflating…the on cycle would not be on the order of tenths of a second but more like a second and a half, depending on the volume of the plumbing…but its worth looking into as a plan b or if someone just wants to mess around

I am not sure if this is similar to what petflora or podracer has used in their non-accumulator setups, but what petflora said about podracer not thinking the accumulator was necessary when you have many mister heads supports the system curve explanation of increasing the dynamic head of the system at the same flow rate

Again, im not tryin to beat a dead horse here, I just love talking fluid mechanics and I love when it is applied to its full potential to grow the most excellent herb known to man

Thanks again,
BD

I am running 2-3 second mist cycles. I watch to see how much spittle (large droplets) comes out before and after. Probably due to small ID stiff wall tubing + short runs+ rez having 3+G of nutes+ being a foot higher than the pump, which is a foot lower than the mist heads, there is very little. spittle. Certainly not enough to have me spending $300 more. Not that I am against the science for an accum. On the contrary. Much respect to all you Mad Scientists.

It is precisely that science (high pressure pump, atomized mist heads, deep cycle timer) that I am employing. The key to an accum is being able to accurately dial in wet times < one second. I did not realize when I purchased it that my Sentinel MDT-1 ($$$$) does not go below one second, and is not accurate at one second. Plan B Make it work. I was struggling until Atomizer took me under his wing.

At the end of the day, IMHO, my method blows away anything short of having an accumulator. So whether I manage to achieve 80-90% (more like 90%+) of what you can get with an accum, then I am happy.

thanks for the input pf...im curious on the amount of water you use each day/week...right now i grow in a recirculating bucket nft hybrid bubbler thing...between my res and my buckets i use about 17 gallons a week and its killing me...once they are old ladies that number will increase

one of the things that initially sparked my interest in high pressure, was the amount of water used compared to other hydro systems...so i did some calculations to see what i can expect to be using if i made the switch...what i found is that the timer has to keep the on cycle to 0.7s on or less or else i would be using more water than i am now

say i have 100 psig right at the misters...then the black 120 degree misting nozzles from cloudtop.com would put out 0.0578 gpm...this can be found by plotting their given specs of gpm vs pressure

with 8 misters in the system, i would be using 0.462 gpm every cycle...at 0.7s on, 180s off, i would use 2.6 gallons a day, or about 18 gal per week

at 0.2s on and 180s off, i would only use 0.74 gallons per day, or 5.2 gallons per week...this is a great condition but from what i understand, very difficult to achieve

the on cycle sounds to me that it is a function of the environment, the water system, and the age of the ladies...if your environment is 100% and the ladies are young enough, 0.2s would be ideal...but the system would have to be dead nuts on too

lets say the plants are fairly young in veg, the environment is ok, but the water system performs weakly and there solenoid that controls the misters is far away from the nozzles...the on cycle might then be 1.5s..as the plants get older, maybe this number goes to 2.5s

at a 1.5s on 180s off, the system would use 5.5 gallons a day! at 2.5s on, 9 gallons a day! of course you could increase the off time to say 5 mins to increase the size of the cycle, but even then it will still take 3.3 gallons per day at 1.5s on and 5.5 gal a day for 2.5s on

this little calculator is telling me that unless the environment is perfect and the system is able to accurately control very short "on" times, and the outcome of these very short on times is maximized by the plant (i.e. the water system is dialed in perfectly), then an hpa system with 8 of these nozzles would cost me more operationally than my slapstick system im currently using

this is a tall order to fill the first time around with hpa too...ive been reading the experiences and it seems like it takes 2-3 grows to get the system working perfectly...thats alotts extra water and nutes ($$) for learning

now there are other factors involved with operating costs obviously...like the number of misters used, the actual pressure supplied to them, and the amount of nutrients used

all things being equal with the amount of nutrients being used, even running at a lower pressure (say 80 psi) will only save you about 5 gallons a week at 2.5s on (still using 34 gallons!)

this all being said, im really curios now to find out exactly how much water people running HPA are actually using

thanks,

BD

attached is the calculator used in the above post...input the pressure of the nozzle, the number of nozzles, the seconds on and the seconds off to calculate the amount of water/nutrient solution used per week/day

BD