irrigation set up

[kannot]

sometime back I was asking about irrigation and pump size.

The  local village water (  Close to Hua  Hin)  is  often off for the hot season, or  on for  just an hour or so, so I  will use my 1  rai lake (8metres  deep) to irrigate  my  trees, Ive done all the calculations and will need a 1-1.5 electric  pump, this is   supplied by 4mm2 ,3  core  cable straight off a 20a breaker etc

Question I need to know is, is it  possible to buy one of these pumps circa 5-7000 baht and make it automatically turn itself off and on, nothing fancy, ie  open a tap and it  kicks  on?  whats required?  or does that mean pressure  tanks etc..last time we discussed the  Hitachi 750 inverter  model but at 22+k for maybe 2-3  months  watering a year seems a  bit ott and the lake water isnt excatly 100%  clean which I fear may break this model?

Although i see the electric  pumps say on the top " constant use"? meaning I assume they must be  run continually not off on as a tap is opened which would mean my  staff opening say 3x10 sprinklers and making sure they are left  open until finished then turned off at the pump first   then closing  the taps  ...which I guess if  i can train him to do that would suffice..............though he aint exactly bright and has a nasty habit of thinking he can do things another way, usually with a catastrophic  result.  

30 sprinklers = 49.8 lit minute  10.95  gallons minute...........all my  pipes  are  buried and 1  inch which in reality is 28mm internal  bore

[Strange]

Ok, 

 

7 minutes ago, kannot said:

need a 1-1.5 electric  pump

 

This is HP?

 

7 minutes ago, kannot said:

Hitachi 750 inverter

 

This pump is something that you were looking at as a viable option? Or would the pump be a type of centrifugal pump with the pick-up in the lake? Something like this, as it would handle junk from your lake way better than the Hitachi unit and way cheaper. 

 

 

I have quite a few easy solutions but just need to understand the pump. 

[kannot]

7 minutes ago, Strange said:

Ok, 

 

 

This is HP?

 

 

This pump is something that you were looking at as a viable option? Or would the pump be a type of centrifugal pump with the pick-up in the lake? Something like this, as it would handle junk from your lake way better than the Hitachi unit and way cheaper. 

 

 

I have quite a few easy solutions but just need to understand the pump. 

Thanks, yep  this  type  of  pump (your photo pick up from lake) 1-1.5hp-2hp need to achieve 40psi at sprinkler head can vary the amount open at any one time they are in multiples of 8-10, so i could open just 10 or 20 or 30 etc etc (150 trees to irrigate spray head sprinklers not rotating) runs  down 28mm diameter pipe over about 100-150metres  level ground with a 6  metre total head which will vary slightly up to 7 metres as pond  level drops all pvc 13.5 flow rate of 30 sprinklers is 11 gallons a minute 20 is 7.3  gallons minute etc

[Strange]

We call those "Junk pumps" at home. Good for dirty stuff. 

 

Easiest way? 

 

Get a pump larger than you think you need and buy a bypass regulator. Run the discharge back to the lake. Set the bypass regulator at 40 psi, and let the regulator vent the overpressure above 40 psi. Can open 10, 20, 30 sprinklers and it won't have a negative effect, it will just vent less back to the lake. 

 

You can keep the valves open, and just use the breaker switch to turn the pump on and off. Make sure there is a foot valve (check valve) on the pick up in the lake. 

 

Since you have a lake it makes it so much easier. Bypass regulator is perfect. 

 

How does that sound? Need more functionality? 

[CGW]

Centrifugal pump, (a pump that uses an impeller to move water) is the correct name.

I used to use one on the house, pump into a pressure vessel with a pressure switch installed.

[Strange]

Just now, CGW said:

Centrifugal pump, (a pump that uses an impeller to move water) is the correct name.

 

28 minutes ago, Strange said:

Or would the pump be a type of centrifugal pump with the pick-up in the lake?

 

[CGW]

^Yes, my brain is not functioning - sorry...........

[Strange]

Just now, CGW said:

^Yes, my brain is not functioning - sorry...........

 

[kannot]

7 minutes ago, Strange said:

We call those "Junk pumps" at home. Good for dirty stuff. 

 

Easiest way? 

 

Get a pump larger than you think you need and buy a bypass regulator. Run the discharge back to the lake. Set the bypass regulator at 40 psi, and let the regulator vent the overpressure above 40 psi. Can open 10, 20, 30 sprinklers and it won't have a negative effect, it will just vent less back to the lake. 

 

You can keep the valves open, and just use the breaker switch to turn the pump on and off. Make sure there is a foot valve (check valve) on the pick up in the lake. 

 

Since you have a lake it makes it so much easier. Bypass regulator is perfect. 

 

How does that sound? Need more functionality? 

nope thats  fine thanks  now have you a  photo of a bypass regulator and where in the set  up does it go ie  ill have a pipe into the lake which is the uptake, that goes into the pump, then the pump out put to the pipework, pipe diagram would be good as im a  bit  new to irrigation? Thanks for your input btw

excuse crude drawing the  pump  will be housed in a block structure  with roof  already  built  speciall next to the lake ie within 3  feet   from the water

[kannot]

Guessing like this ?

[Strange]

Just now, kannot said:

Guessing like this ?

 

Yep, thats right. 

 

Real quick, do you have any idea approximately what size the intake and outflow of the pump will be? I will try and find you an appropriate diagram & link. 

 

You are also going to need a pressure switch to protect everything from accidental fault from the regulator. Its nothing really, just a safeguard incase there is overpressure more than what you want or way over and breaks pipe & sprinklers. Ill get you an image for that too. 

[Strange]

Pressure relief valve. This does NOT go inline between the pump and your sprinklers. It would go on a "T" piece and vent overpressure. This is just an example of a simple one I found, the are a lot of different styles, sizes, standards, etc... This one is the simplest. They make one with a pressure relief switch and built in gauge so you can relieve pressure at the pump for service. 

 

There is only 1 in and 1 out, goes off to the side, NOT pump in water out. And gotta get one same size as ur pump. This one is 3/4"

 

 

[Strange]

Pressure switch commonly found at any local isaan/thailand construction supply place. This one is adjustable. Cut in and Cut out. Only really need "Cut out" but you can adjust it so its set at like 30 psi on (on all the time basically in this setup) and 50 psi off (overpressure). They generally only adjust in 20 PSI increments. But they are sold everywhere and will work and cost nothing. Taps in right after the pump inline with the sprinklers. 

 

 

 

[Strange]

Then just a few PSI/Bar gauges and that check valve at the foot of the pick up and should be ok. 

[Strange]

1 hour ago, CGW said:

I used to use one on the house, pump into a pressure vessel with a pressure switch installed.

 

Yep that is the system I was gonna recommend next but its a bit more expensive and complicated. 

[Strange]

Something like this:

 

[Hereinthailand]

Make it simple and put a timer on the pump, set it for two times a day early morning and evening for better tree growth. I think your pressure switch on this system will be more trouble than its worth.

[kannot]

1 hour ago, Strange said:

Something like this:

 

ah  I  know this system, heres  one I did earlier this year for potable  water but  had  5  foot high pressure  vessel,  Ill check the pump info next time Im down global house, I already have pressure switches and get back to you

[kannot]

8 minutes ago, Hereinthailand said:

Make it simple and put a timer on the pump, set it for two times a day early morning and evening for better tree growth. I think your pressure switch on this system will be more trouble than its worth.

no need for a  timer, i  have  staff who  will do it and i may leave the pressure switch  out as it wont  run for more than about 1  hour per  day with the staff always checking the sprinklers etc any problems and it should just drain straight back to the pond but would be spotted quickly, trying to keep this simple  and cheap as only  used 2-3  months per year

[Hereinthailand]

Iin your first post you worried about staff not doing their job, a timer doesnt have that problem, up to you.

[Strange]

37 minutes ago, kannot said:

ah  I  know this system, heres  one I did earlier this year for potable  water but  had  5  foot high pressure  vessel,  Ill check the pump info next time Im down global house, I already have pressure switches and get back to you

 

Yep good system there. Looks like submersible pump, pressure switch, pressure tank, then point of use? 40 psi on and 60 psi off on the switch? If thats a submersible pump in there thats a pro setup. Its what we do in the states for homes on wells. No need storage tank or auxiliary pressure pump. Pressure tank takes care of that. 

[Strange]

38 minutes ago, kannot said:

no need for a  timer, i  have  staff who  will do it and i may leave the pressure switch  out as it wont  run for more than about 1  hour per  day with the staff always checking the sprinklers etc any problems and it should just drain straight back to the pond but would be spotted quickly, trying to keep this simple  and cheap as only  used 2-3  months per year

 

Id put it in. Costs nothing, wiring is already there. If the bypass fails or gets clogged you need something to switch the pump off. Cant trust the staff to watch this kinda thing all the time. Its like 2 minutes extra work. Since you know about switches you can find a simple 80 psi cutoff unit just to protect the system. Regular pressure switch will work just fine too. 

 

You having a lake right there for a simple return is the cheapest/easiest way to maintain your desired pressure. If no lake then you'd need another pressure tank setup. 

[kannot]

1 hour ago, Hereinthailand said:

Iin your first post you worried about staff not doing their job, a timer doesnt have that problem, up to you.

Yeah  I meant in turning the taps off "before" turning off the pump letting the pressure  build up until "boom"

Theyll remember to turn it  on and off alright thats wont be a problem just the order to do it in thats why the  pressure relief valve was necessary, othe r possible problem is power  cuts although we dont get too many seem to come in spits n spurts, nothing for months then  3-4 in a  week

[kannot]

34 minutes ago, Strange said:

 

Yep good system there. Looks like submersible pump, pressure switch, pressure tank, then point of use? 40 psi on and 60 psi off on the switch? If thats a submersible pump in there thats a pro setup. Its what we do in the states for homes on wells. No need storage tank or auxiliary pressure pump. Pressure tank takes care of that. 

Yeah I did two of these myself, couldnt trust anyone roud here to do it, The tank was pricey Grundfos the "manifold" I got in America stainless steel brought over by a friend stupidly made in China but couldnt find a decent one here, wells  50 metres  deep 6000 lits  an hour, I have it at 32psi on 52  off ,tank pressure 30psi, its a  300 litre  tank, actually  holds about 90 litres of water before refilling also a  5  bar pressure  relief  valve

[Strange]

23 minutes ago, kannot said:

Yeah I did two of these myself, couldnt trust anyone roud here to do it, The tank was pricey Grundfos the "manifold" I got in America stainless steel brought over by a friend stupidly made in China but couldnt find a decent one here, wells  50 metres  deep 6000 lits  an hour, I have it at 32psi on 52  off ,tank pressure 30psi, its a  300 litre  tank, actually  holds about 90 litres of water before refilling also a  5  bar pressure  relief  valve

 

Since you clearly know ur stuff and you get what I'm saying with the pressure relief valve, they make tons of better ones that flow better & regulate pressure better. That pic I showed was basically a safety bypass similar to the one on your submersible & was minimum 50 psi. Not really meant to be 'bypassing' all the time but its mechanical and will still work just fine as a cheapie setup. But it makes the pressure switch even more important especially if your staff fiddle with valves & stuff. They make way better ones. Tons on aliexpress and eBay. 

[kannot]

4 minutes ago, Strange said:

 

Since you clearly know ur stuff and you get what I'm saying with the pressure relief valve, they make tons of better ones that flow better & regulate pressure better. That pic I showed was basically a safety bypass similar to the one on your submersible & was minimum 50 psi. Not really meant to be 'bypassing' all the time but its mechanical and will still work just fine as a cheapie setup. But it makes the pressure switch even more important especially if your staff fiddle with valves & stuff. They make way better ones. Tons on aliexpress and eBay. 

Thats  ok I have two ones I got as spare from Grundfos (Telemechanique is the name) as seen in the picture they are  well made and  fully adjustable, this is my second well, excellent  drinkable water ( tested in BKK) but low  yield about 500 -1000 lit an hour, i can swap between the two wells  to supply the two houses in fact both are connected but split between two places, if  one fails I can simply open two valves and revert to the other , basically the same as the first but with 200 litre  tank, same pressure switch about 1200 baht I think they were.

In the background far left is where the  other  supply comes in, it  runs down 100 metres of hdpe 1.5  inch from the other  well

[kannot]

5 hours ago, Strange said:

 

Yep, thats right. 

 

Real quick, do you have any idea approximately what size the intake and outflow of the pump will be? I will try and find you an appropriate diagram & link. 

 

You are also going to need a pressure switch to protect everything from accidental fault from the regulator. Its nothing really, just a safeguard incase there is overpressure more than what you want or way over and breaks pipe & sprinklers. Ill get you an image for that too. 

The one Ive been looking at "Lucky Pro"  1.5hp intake is about 1.5-2 inch OUTFLOW is definitely 1  inch as I screwed a  1  inch fitting into the end of it yesterday and this  will match all my pipework to the sprinklers

Might be this  one  I   think but many different  models

http://www.lucky-pro.com/products/Centrifugal_Pump/MCP25160A.asp

[Strange]

22 minutes ago, kannot said:

same pressure switch about 1200 baht I think they were.

 

Here is a cheapie I had in my desk. Same thing used on those "Lucky Star" "Constant Pressure" pumps with the little pressure tank underneath. Sold everywhere this one was like 150 baht. Adjustment screw on top. Good for a cheapie setup & can buy a replacement at the corner hardware store without having to go into town and make a day out of it. 

 

[kannot]

3 minutes ago, Strange said:

 

Here is a cheapie I had in my desk. Same thing used on those "Lucky Star" "Constant Pressure" pumps with the little pressure tank underneath. Sold everywhere this one was like 150 baht. Adjustment screw on top. Good for a cheapie setup & can buy a replacement at the corner hardware store without having to go into town and make a day out of it. 

 

Yeah , Ive got  plenty of spares here, I usually  buy at least one spare of  most things as stuff I use is  often not available easily or  the quality is so poor I  just decide not to use it.

Heres 2  different type i have here the right one is a cheap Polish product the left is the telemechanique

[Strange]

2 minutes ago, kannot said:

Yeah , Ive got  plenty of spares here, I usually  buy at least one spare of  most things as stuff I use is  often not available easily or  the quality is so poor I  just decide not to use it.

Heres 2  different type i have here the right one is a cheap Polish product the left is the telemechanique

 

One on the right is the kind I'm used to at home. The cheap polish one. The one in my pic is the REAL cheap one lol