12V pump duty cycle

[beddhist]

As we are planting a lot of trees I bought a 12V water pump, to be installed in a tub with battery, which can be pulled along the irrigation channels. This is the pump:

 

https://www.lazada.co.th/products/dc-12v-i407734253-s792008503.html

 

When it arrived I read on the box: "Caution Duty period: 30 minutes"

This is not stated in the ad and I have until 30/1 to return it.

 

We estimate that it would be used with a stop-start switch for about 1.5 hours at a time. Will I take too great a risk to keep it? I'm inclined to return it.

Does anybody here know about this kind of thing?

 

Thanks,

Peter.

[Metropolitian]

The title on the advert tells ' เครื่องสูบน้ำมันต่อพ่วงแบตเตอรี่ ' and 'น้ำมัน' means oil, and one of the photo confirms that this is not primairly designed as a waterpump but oilpump.

Clear is that with the testing of this pump and the results are based on pumping oil it need to be 'cooled down' after pumping 1200liters of oil.

 

But nothing is lost, it can work as a water pump.

 

The pumping capacity for water is 200 liter in 8 minutes, and for diesel 200 liter in 4 minutes.

Don't use for gasoline or other flammable fluids. (Diesel isn't as it need compression and mixture to be flammable)

 

One of the main use for these sort of pumps is to pump from wells (up to 10 meters) into containers, which filled full can use the gravity/siphoning method to water the field/gardens.

[Metropolitian]

1 minute ago, Metropolitian said:

and the results are based on pumping oil

Oil which has a thicker viscosity, hence the pump need to work harder and will eventually get too hot so they put a virtual time limit on using these pump.

The same will happen with thin viscosity (close to air), like a car giving full gas with the transmission in neutral.

 

Water is between this,  without specification it is hard to tell how long the maximum runtime will be.

 

Is there no manual with it with specification when use with other fluids?

[beddhist]

Thanks for your reply. In the questions the seller confirmed that it can pump water. I am a little surprised that it pumps diesel twice as fast. I don't want to open the sealed box, if I don't keep it. I think heat is exactly the problem and the water in the canals will be hot in the hot season, so more reasons to send it back.

 

On the other hand, 1000B is not excessively expensive to give it a shot. Plus, I have not found another suitable pump on Shoppee or Lazada. They are either too slow, submersible only or short duty cycle. Perhaps I should visit some of the local stores, but I'm not holding my breath.

[VocalNeal]

At 155W I think the battery will run out before the motor does. Are you dragging the empty tub and how are you going to drag a car battery? 

 

Seems like a lot of work. 

 

200l in 8 mins is a standard 55 gal drum. 

 

In your plan will it need to run for the whole 1.5 hrs? 

Edited January 27, 2020 by VocalNeal

[beddhist]

It will float in a tub, so pulling will be very easy. We have seen a guy down the road do this with a petrol powered pump. I'm planning to "borrow" a 45 Ah LiFePO4 battery from our solar system. I have 4 of them. We have a bit over 1 ha and we are planting most of it in trees, probably around 1000 of them. My wife says they need watering only during the first year. After that their roots will be deep enough to get water from the canals. Otherwise I would have installed irrigation pipes. We have about 100 trees so far and she waters them daily with the small bucket on a long pole that all farmers have. It takes 1.5 hours...

[Metropolitian]

Consider a water container for at the trees.

They can be filled with that pump 30-45 min from bottom to top.

They come in 600-1000 liters.

When the water in the canal dries out or get contained you would still have a bit overlap.

 

 

[beddhist]

We have a 500 l water tank that our well pump fills in about 5 mins. That same pump can also rapidly top up the existing canal.

 

The 1.5 h running time came from the time it takes to water the existing trees with the pole bucket. It actually needs to run a lot longer and in stop/start mode. (Meaning: pump water to a tree, let go of the switch, move to the next one, repeat, ...) I wonder whether I need a much larger pump for more trees, although they won't all need watering at the same time. She can't plant them that fast!

[Metropolitian]

You haven't opened the box so couldn't confirm yet but at the ads you linked in the OP I see in the photo of the actual pump an sticker attached.

 

 

That label looks very like this one: 

Read the text at 'attenSion' , it says water prohibited.

 

I can't deny my feeling that it would be affected internally by corrosion which will not occur with diesel.

So if you want to keep this pump, strongly advised is to clean and dry the pump after use.

 

 

BTW, the idea of the floating tub and tug it all along the canal with the batteries in the tub. I like that.

 

[beddhist]

Unfortunately none of the pictures show on my PC. I only get a black box with a twirly thing for a while, then a broken picture icon. Looking at some of the almost identical looking alternatives, some are advertised as oil or fuel pumps only, some have water mentioned as well. Some mention a duty cycle of 30 mins, some don't. Funny: "high quality and heat resistant" "use for 30 mins, rest 10 mins" "overheat switch may cut off".

 

I searched for pumps with the word "continuous": none.

Edited January 27, 2020 by beddhist

[VocalNeal]

A small gasoline powered unit is only about 3600 baht then do it like this?

 

 

But it will still probably take almost as much time as the traditional bucket.

[beddhist]

That's what the guy down the road uses, except the idea is to get it to each tree individually. No need to make the weeds grow faster and waste the water. But I do want to get away from Dino juice, where possible.

 

I've just discovered that searching for 'solar pump' yields much better results. I'll return the pump tomorrow and get another.

 

Interesting: all the pictures above have magically appeared.