Two Pumps in the Desert

[waleed]

Hello ,

I have two pumps , which I want only one to be ON at any given time. The pumps are triggered by several event , i.e. tank empty , irrigation pressure (manual open one of the valves) , irrigation controller.. etc.

I am thinking of using two ON delay timers with say 2 min. on delay on each pump , the timer will connect to the AB of the pump contractors. Now if the input to the timer X is on , the other will be off and vice versa.

So if one of the pumps (well) is already on , and I tried to switch on the other pump (booster) , the well pump will be immediately switched off and the booster pump will be on after 2 min.

Will this work ? Is there a better way to control the pumps ?

Many thanks for such great forum and great people ..

 

[Silly Sausage]

I see the idiots are flocking in to roost.

:smilielol5:

 

[Bobster]

This problem is solved with a selector switch, 2 contactors with mechanical interlocks. Jobs done, yes over here it would be more involved.

 

[ian.settle1]

2 camels going round in circles driving a couple of pumps might be better.

 

[Engineer54]

Originally Posted by waleed
The current installation is perfectly OK , the 30HP submersible pump with its Schneider control panel is working fine. The only thing here is that I have acquired a new land with which I need the addition of the booster pump. As for Saudi Arabia, you may need to read more on the country's development.
Thank you

That statement is not quite true is it?? That submersible pump is at the end of almost half a kilometre of 50mm reducing to 35mm cable, and you want to add another pump to this set-up!!!
What is the voltage supply to you're farm 380/220V or 220/127V ??

Originally Posted by GEOFF S
At 240 meter's and 55 amps you are pretty much at 5%(approximation BS7671), not taking into account the further 210 meters to the pump.

If we move away from the 5%, Do you have your own Transformer? If you can calulate from source.

Cheers

And my reply...
That was going to be my next observation This 50/35mm cable is already past its limit when taking VD into account, and won't be doing the pump it's currently supplying any favours either!! To be honest you need to run another cable, and if you use another 50mm you can then use the present cable in combination with the new cable (eg Parallel supply). Either that, or calculate whether you can achieve your needs via a suitable TX close to the well/tank installation...

Depending on the tolerance of your pump, the voltage drop may well be already slowly destroying your existing pump. So it could be far from being OK as you put it. You haven't given us any circuit testing data/values or even if the OCPD is suitable or has a sufficient installation Zs value to operate in a suitable time range etc...

.........................................................................................

Waleed, so many blatant lies are written about the past and ongoing development achievements of Saudi as well as the Gulf States by the various government ministry's you'd be foolish to believe most of them. I'm not saying that Saudi's development isn't progressing at a pace, of course it is, but sometimes that development is not all it's being made out to be. As a matter of interest, where are you located in Saudi?

 

[Geordie Spark]

...And after ALL the technology,diplomacy,and politics...it takes a Geordie to bring it back to a good old threesome joke :joker:

Well to be perfectly honest when I first saw the title of the thread I thought it could be about two flatulent camels.

 

[Besoeker]

Keep it simple, put a changeover switch in!

And possibly a mechanical interlock between the two contactors.

 

[Jonspark]

I see the idiots are flocking in to roost.

Were you cranky as a baby?

 

[ian.settle1]

Were you cranky as a baby?

Oy you leave the forum Grumpy Git alone.

 

[Knobhead]

Were you cranky as a baby?

Yes but I’m improving with age.

 

[Jonspark]

you should be pretty damn perfect by now then..:smilewinkgrin:

 

[Knobhead]

I’m beyond perfection.