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Solar pump 1500w 110vdc no batteries, suitable panel config?

yobits

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Mar 6, 2023
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Asia
total solar noob here,
i have just purchased a solar water pump that comes with controller
i am hoping i can run this directly from panels without batteries using 4 x 600w panels desirably
details of the pump controller
max input: 15A
Max Open circuit voltage: <200v
MPPT voltage range: 110v-150v

the pump
110VDC
1500W
max head: 17m
max flow: 55m3/h

when reading the manual it gives examples of 265w and 330w panels being used (8 for either, 2x4 series)
this example is based on panels with
max power: 330w
short circuit current: 9.33A
max power current: 7.15A
Open circuit voltage: 45.64v
max power voltage: 34.28v

when searching for such panels i do not find any with low max current,
all panels available are 9-10A
so i assume i should not follow their example,
as current would be higher than the controllers max input current of 15A
i was hoping to use 600w panels to save on space and seeing they recommend 8x 265-330w panels, i assumed 4x 600w would suffice
the 600w panels available are
Maximum Power Voltage(VMP):36V
Open-Circuit Voltage(VOC):42V
Maximum Power Current(IMP):9.72A
Short-Circuit Current(ISC):10.8A

would 4 of these 600w panels in series be sufficient for the pump ?
is 4 enough or is 5 better ?
or do i need to find different panels for better current?
as at max 4 x 36v =144v x 9.72A = 1399W
but 5 x 36v = 180v x 9.72A = 1749W
but output will be 110v, is the output current equal to the input current?

about the pump, it will likely be running for an hour or two at most each day in the morning once there is enough sun
will be sucking water from pond about 3m down from the pump, just looking for as much pressure as possible as this will be connected to high power sprinklers

thanks in advance to any replies this is all new to myself (sort of)
 
Last edited:
the 600w panels available are
Maximum Power Voltage(VMP):36V
Open-Circuit Voltage(VOC):42V
Maximum Power Current(IMP):9.72A
Short-Circuit Current(ISC):10.8A
Welcome to the forum!

Those specs don't appear to line up with a 600w panel.
36 x 9.72 = 350 watts

You'll still pump water with panels since you are in the MPPT range but I suspect it will struggle to run your sprinklers properly.

What pressure do your sprinklers need? 17m of head might not be enough to operate them.

How cold does it get where you are? If it gets below 15C or so I'd avoid getting Voc of the array over 175v so stick with 4 modules in series as 5 could damage your controller.
 
Welcome to the forum!

Those specs don't appear to line up with a 600w panel.
36 x 9.72 = 350 watts

You'll still pump water with panels since you are in the MPPT range but I suspect it will struggle to run your sprinklers properly.

What pressure do your sprinklers need? 17m of head might not be enough to operate them.

How cold does it get where you are? If it gets below 15C or so I'd avoid getting Voc of the array over 175v so stick with 4 modules in series as 5 could damage your controller.
thanks for reply
my thoughts exactly about 600w panels, that's why i have been scratching my head
and those panels with those specs are sold by a few sellers here
after looking at more 550w panels, it seems those 600w panels might just be dodgy panels being sold, such stuff happens here
but the lower watt panels will still go over the max current input if running any in parallel
and the specs for panels they use for examples in the manual simply don't exist on any panels i have seen available
as all are above 8A current
i doubt it ever gets below 15C here,
15C is probably about the absolute lowest temp at night during coldest time of year where i am
average low on coldest time of year is 18C
i have not purchased the sprinkler heads yet, but obviously i want as much coverage as possible
i have just found 550w panels which seem to have correct specs
current: 13.45A
voc: 49.62v
max v: 40.9v
these seem to be what i need as 4 in series gives me
2200w
voc: 198.48v
max v: 163.6v
but now i worry about 4 of these in series damaging the controller due to your comment above lol
but the example in manual is 182.56v and 14.3A
the voc would still be under 200v if only just
 
searching 500w panels and above
the only panel available with a lower VOC is a 540w panel
540w.panel.png
 
but now i worry about 4 of these in series damaging the controller due to your comment above lol
but the example in manual is 182.56v and 14.3A
the voc would still be under 200v if only just
That's probably too close. Best practice is to use the record low temp.

As you are experiencing, larger panels for water pumping will often cause this problem because the voltage can be hard to fine tune. Complete solar pumping kits often come with 100 watts panels because it's so easy to fine tune volts and wattage requirements and they are easily shipped by normal means.

I'd still be concerned that pump might not generate enough pressure to work those sprinklers properly.
 
would you think a pump with better head but much less volume would be better?
i went for the pump with the most flow
they have well pumps available with max head of 90m
but the flow rate is 1/10 of the pump i currently have which does max 50,000 Litre/hour

as for panels, the low max current input on the controller seems to be my main issue
if the controller had max 20A input then i would not have any issue with voltage as could run panels in parallel
even with 100w/120w panels
voc: 20/25v
imp: 5.8A
it works out the same if i am to get 1.3 x the power of the pump (1950w)

would a small diaphragm pump at the sprinkler help if more pressure is needed?
luckily am yet to purchase anything else so still have options
the sprinklers will also be about 2-4m below the level of the pump if this helps at all
 
ok, seems i can get there with 170w panel i have found
one thing i also done which i should have done at start but foolishly did not
was to confirm specs on the controller instead of just trusting the manual
controller i9tself states
max current 17A (woohoo)
max voc: 185v

have found 170w panel (some 100/120/150w panels also suitable but very expensive)
Spec solar panel 170w monoOpen
Circuit voltage(Voc) :23.8v
Short Circuit Current(Isc) :9.52A
Max powerVoltage(Vmp) :20.5v
Max power current(Imp) :8.32A
Mac system Voltage :1000VDC
Size of module :150*67*3 cm.

so i am assuming 12 of these panels running 2x6 should suffice
voc: 142.8v
vmp: 123v
imp: 16.64A

or would 14 be better at 2x7 ?
voc: 166.6v
vmp: 143.5v
imp: 16.64A
 
this is the pump i have

from the video they are using 8 x 330w panels
however their controller is different to mine although likely same spec i expect
not sure on any details of their panels though
 
would you think a pump with better head but much less volume would be better?
I think it's best to first to make sure you can get the head you need because without the ability to make it many pumps will move no water at all.

As you've already figured out it's best to identify exactly what you're trying to do before anything is purchased.

What is the model number of your pump? Do you have it's pump curve? With the pump curve I can do a much better job of helping you.
 
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