Simple.. low watt solar pumping for water garden..

hawaiianfishkeehawaiianfishkee Registered Users Posts: 11
Hey folks... im new here at wind and solar and i have a few questions...first post, so bare with me... if been doing some research(not enough) about pv modules and dc powered pumps... i recently ordered a small 9x11 12v solar panel and im trying to run a small water pump for my water garden... my pops wont allow me to use anymore wall outlets :( but i figure i should be doing this little project just to get a grip on future technology :) ..
the solar panel i got is a silicon solar module-(on box)

Peak power(Pm) 5w
Open Circuit Voltage(Voc) 21.6V
Short Circuit(isc) .30A
Max power Voltage(Vmp) 17.6V
Max Power current(Imp) .28A
Working temperature -45C-+85C
Tolerance +_ 5%

i know the module is working because i attached it to a volt meter.. but sadly ihad know idea what i was reading - it's the swing meter not digital

the pump is 12VCD 3.8L 12V Mini DC submersible Water Oil Pump for CPU Cooling Small Pond or HHO System i picked up on amazon for 15 bucks -(on website)

Input: 9V-12VOutput: 3.8L/m Range: 2.5M (8ft horizon) @12V
Current: [email protected]
Intake: 13.8mm/9mm Dia.
Outlet: 7.2mm/5mm Dia.
Life span: > 20,[email protected] 1600rpm~4200rpm
Noise: << 30dB
Working Temp: 70'C
Envir Temp: <40'C
Size(L*W*D): 2.36"x1.3"x1.6" (59mm X 33mm X 41mm)
Weight (net): 5.0oz

i'm new to this and i suck at electronic wiring, i kinda have a grip on the terms but not really :/
the module and the pump have two serparate wire thickness and colors..
the module is blue and brown and the pump is red and black..
i connected them today in the sun and nothing happened... just a high pitched frequency noise...

can anyone help me on what i don't know, what i need, and how i can make this project work? i kinda wanted to accomplishe this project for earth day that's coming up right around the corner... thanks in advanced

Comments

  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: Simple.. low watt solar pumping for water garden..

    Welcome to the forum.

    You have a couple of problems with your set up. The first is that the panel can not put out enough power to run the pump. Look at its maximum current output: 0.28 Amps. That's 280 mA. What does the pump motor require? 500 mA. Right there you're shut down.

    The other issue is that the panel is a current source, whereas the pump wants a Voltage source to run from. The usual way of getting around both these problems is to add a battery. The pump runs off the battery, and the panel recharges the battery. The battery "evens out" the current and Voltage to give consistent power. But a 5 Watt panel isn't going to charge much battery. You're looking at less than 5 Amp hours, and the need for some regulation circuitry.

    There are others here who are skilled in the area of experimentation and "hobbyist" electronics. I'm sure they'll have some suggestions.
  • hawaiianfishkeehawaiianfishkee Registered Users Posts: 11
    Re: Simple.. low watt solar pumping for water garden..

    Thanks coot... dang.. should i look at the voltage?(both are rated at 12v) or wattage?(module is 5w and pump is 6w) or amps? if the amount of amps needed for pump is 500 and one solar module is 280mA then wouldn't 2 solar panels at 560mA run the pump.. but then ofcourse there would be a total of 24 volts and 10 watts, correct?
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: Simple.. low watt solar pumping for water garden..

    Merely adding another panel will not solve the problem. The pump wants a fairly stable 12 Volt power supply. Unlike batteries, solar panels are a current source not a Voltage source. The panel(s) will put out a stable current, but unstable Voltage. Without the battery in the circuit you could hit the pump with 500 mA @ 17.6 Volts momentarily - possibly just long enough to fry it without actually getting it to pump anything.

    There are large direct solar powered pumps. Look here: http://www.solar-electric.com/sun-pumps.html
    Note that these are rather larger than what you're working with, and that they use much more panel and a controller which takes the higher panel output and converts it to a stable current over a variable Voltage range which is within the operating range of the pump. But these systems are designed to work that way. You'll also notice they are expensive.

    It may be possible to build your own "miniature" version of the controller. Two panels regulated to 12 VDC on a large capacitor or some such. That is not my area of expertise, as I haven't done any circuit design in 25+ years!

    And tossing out that little factoid has just boggled my mind. :p
  • hawaiianfishkeehawaiianfishkee Registered Users Posts: 11
    Re: Simple.. low watt solar pumping for water garden..

    dang im at a loss... has anyone else done this sort of thing?
  • hawaiianfishkeehawaiianfishkee Registered Users Posts: 11
    Re: Simple.. low watt solar pumping for water garden..

    thanks coot!! so maybe 2 solar panels and adding a linear current booster or a controller to stablize voltage? do you think it would be able to keep the voltage at 12v and boost the amperage to what i need?
  • BB.BB. Super Moderators, Administrators Posts: 28,768 admin
    Re: Simple.. low watt solar pumping for water garden..

    First, you should learn about electricity... Volts, Amps, Ohms and the basic math behind it...

    Here is a nice set of web pages "Electricity for Boaters"--Very similar to Solar PV Systems (batteries, switches, generators, loads, etc.)... The only thing added is solar panels.

    And here is a PDF quick course on How to Use an Analog (Mechanical) VOM (Volt Ohm Meters).

    For your use, you can try:
    One Panel
    [FONT=Fixedsys]                              Positive      Negative
    +=blue===[solar panel]===brown===red===motor==black=+
    |                                                   |
    +===================================================+
    [/FONT]
    
    Try one panel first and place it in Full Sun... The pump will probably not run or run very slowly.

    Next, place two panels (brown to brown; and blue to blue) in parallel. Roughly, this should run the pump in full sun.

    And, if you want, you can try three and four solar panels in parallel..

    If the pump runs too fast, remove one panel. If the pump runs OK with more panels in parallel, you will just be able to run the pump when the sun is not at noon time in the sky.

    I believe the solar panel Blue=Negative=Black, and Brown=Positive=Red.

    The solar panels in full sun are a bit more voltage than the motor is designed for--So test one/two/three/etc. panels--one at a time and don't add any more if the motor sounds too fast.

    Current wise, each panel is ~0.28 Amps... In theory, two panels in parallel should be about to supply just about the 0.50 amps required by the motor in full sun.

    If the motor does not turn in the correct direction (may not pump much water), then try reversing the solar panel to motor wiring.

    Most small motors are just "Brush" type DC motors. These motors are pretty rugged and you will not damage it if you connect the panel backwards (for example).

    If, however the motor has electronics (like DC Fans for Computers), reversing the +/- connections and/or too high of voltage, it can ruin the pump electronics without any warning (Brush-less Motors).

    You might also want to look at purchasing a Snap Circuit kit and build the projects to learn about electricity.

    And yes, a Linear Current Booster can do what you want, but they are not cheap.

    7 amp Linear Current Booster/Pump Driver $91.00
    wind-sun_2149_57822091 Used to control and power a DC motor from a solar panel. The unit prevents stalling of the motor under less than full sun condition. The power of the sun is transformed to ...
    And may not be a good match for such a small pump motor and solar panels... Then again, it may work OK.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • hawaiianfishkeehawaiianfishkee Registered Users Posts: 11
    Re: Simple.. low watt solar pumping for water garden..
    BB. wrote: »
    First, you should learn about electricity... Volts, Amps, Ohms and the basic math behind it...

    Here is a nice set of web pages "Electricity for Boaters"--Very similar to Solar PV Systems (batteries, switches, generators, loads, etc.)... The only thing added is solar panels.

    And here is a PDF quick course on How to Use an Analog (Mechanical) VOM (Volt Ohm Meters).

    For your use, you can try:
    One Panel
    [FONT=Fixedsys]                              Positive      Negative
    +=blue===[solar panel]===brown===red===motor==black=+
    |                                                   |
    +===================================================+
    [/FONT]
    
    Try one panel first and place it in Full Sun... The pump will probably not run or run very slowly.

    Next, place two panels (brown to brown; and blue to blue) in parallel. Roughly, this should run the pump in full sun.

    And, if you want, you can try three and four solar panels in parallel..

    If the pump runs too fast, remove one panel. If the pump runs OK with more panels in parallel, you will just be able to run the pump when the sun is not at noon time in the sky.

    I believe the solar panel Blue=Negative=Black, and Brown=Positive=Red.

    The solar panels in full sun are a bit more voltage than the motor is designed for--So test one/two/three/etc. panels--one at a time and don't add any more if the motor sounds too fast.

    Current wise, each panel is ~0.28 Amps... In theory, two panels in parallel should be about to supply just about the 0.50 amps required by the motor in full sun.

    If the motor does not turn in the correct direction (may not pump much water), then try reversing the solar panel to motor wiring.

    Most small motors are just "Brush" type DC motors. These motors are pretty rugged and you will not damage it if you connect the panel backwards (for example).

    If, however the motor has electronics (like DC Fans for Computers), reversing the +/- connections and/or too high of voltage, it can ruin the pump electronics without any warning (Brush-less Motors).

    You might also want to look at purchasing a Snap Circuit kit and build the projects to learn about electricity.

    And yes, a Linear Current Booster can do what you want, but they are not cheap.

    7 amp Linear Current Booster/Pump Driver $91.00
    wind-sun_2149_57822091 Used to control and power a DC motor from a solar panel. The unit prevents stalling of the motor under less than full sun condition. The power of the sun is transformed to ...
    And may not be a good match for such a small pump motor and solar panels... Then again, it may work OK.

    -Bill

    HEY!! THANKS A TUN BILL!!! i'm going to try to freshen up on the electrical terms with the links that you've provided.. I am sure that you are help more than just me while answering my question... i am going to buy another solar panel soon and do the parallel connection... im also going to try to find a low priced booster that can regulate the voltage... Thanks you guys for the input i will keep you posted on the progresss...
  • BB.BB. Super Moderators, Administrators Posts: 28,768 admin
    Re: Simple.. low watt solar pumping for water garden..

    The interaction between a solar panel and a DC motor is fairly complex...

    We are all very familiar with "Voltage Sources"... These are batteries (flashlight, car, etc.) and voltage sources (like computer power supplies and even your 120 VAC wall outlet).

    You plug a load into a battery/voltage source... The Battery will stay near 12 volts DC, your wall outlet will stay near 120 VAC.

    Solar panels are, basically, the exact opposite of a Battery... They are Current Sources...

    They output a ~constant current based on how much sunlight is falling on the panels / solar cells.

    For example, in full sun your panel will about ~0.28 amps (Imp--current maxium power) from 0 Volts to ~17.6 volts (Vmp--Voltage maximum power).

    And DC motors are "constant" power devices... One of the equations for power is:
    • Power = Volts * Current
    A solar panel will output 0.29 amps from 0-17.6 volt... Notice that you get Zero Power when voltage = 0 Volts. And maximum power will be at 17.6 volts Vmp (above Vmp, the output current falls until Voc--Voltage open circuit--i.e., no current flow, no power).

    A current booster "matches" the Vmp*Imp from the solar panel and attempts to transfer maximum Vmotor*Imotor energy.

    It is not a simple concept to understand--studying the math, learning to make measurements with a VOM / DMM (digital multi-meter) is a good sart.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • hawaiianfishkeehawaiianfishkee Registered Users Posts: 11
    Re: Simple.. low watt solar pumping for water garden..

    I figured it wouldn't be that hard to do since they sell kits online... and there are a lot of videos on youtube with people using direct connections from small PV modules to small water pumps.. I just don't see how they make it seem so easy... I was trying to match the wattage between the two(module-pump) and i figured since they are both rated at 12v it wouldn't be that hard... i did not take amperage into consideration..
    check it out-

    http://www.youtube.com/watch?v=a37c9SBNZ_U

    http://www.youtube.com/watch?v=VgkDdTXmYzM&feature=related

    http://www.youtube.com/watch?v=AaIwdQ03U7o&feature=related

    http://www.youtube.com/watch?v=0nEEt5zxvKQ

    I've tried to contact these people but they haven't responded... So i think i'm going to try to buy another PV module to see if the pump even runs... Then of course if it does run, then i'll have too much voltage and risk burning out the pump... so i'll probably need a regulator or something right?
  • peterakopeterako Solar Expert Posts: 144 ✭✭✭✭✭
    Re: Simple.. low watt solar pumping for water garden..

    The easy setup from panel to pump are special design pumps.
    only on sale as a set.
    To start your pump you need to have more current for a moment to start.

    from the noise that you have it is clear there is a electronic inside running high freq.
    I am not sure if this electronic can handle a startup by slow rising voltage. as from a pv panel.

    Maybe it is better to sommething else with the panel like connecting to a battery and leds

    greetings from greece
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: Simple.. low watt solar pumping for water garden..

    There ought to be a big warning carved in stone: BEWARE YOUTUBE VIDEOS.
    Anyone can make one of those and get it out there claiming anything, and people assume that because you "see" it it is real. A large percentage of these videos are faked. Just watch Mythbusters and see.

    Even for the ones that aren't faked, the "anyone can do this at home - it's easy" attitude is often exaggerated. I don't know why there's so many people out there getting their jollies from fooling the public, but there are.

    That's not a slur on Youtube en toto, just a general warning that you shouldn't take things presented there as absolute fact.
  • BB.BB. Super Moderators, Administrators Posts: 28,768 admin
    Re: Simple.. low watt solar pumping for water garden..

    You can add a regulator and/or a battery to stabilize the voltage and provide power when the sun is not usable.

    However, it adds complexity and costs. Also, batteries are very sensitive to how they are discharged and charged... Improper battery maintenance/operation can kill a battery in months, or even weeks.

    Solar + Charge Controller + Batteries is really great for off-grid power, but it doubles the cost/complexity of the system and you will get ~1/2 the power (for same solar panels).

    And adding batteries usually requires manual controller by the owner to make sure the batteries are not take to "dead" at night or in bad weather.

    It is certainly a learning experience. :roll:;)

    But, after a bit of work (and a lot of $$$), you will appreciate why we tell people to use utility power when available. It is much cheaper and easier to design and use.

    And don't overlook the danger caused by Solar PV and batteries. Even "car sized" 12 volt batteries are incredibly dangerous if not treated with respect. You can start a fire with overheated wiring or over charged battery. Or even have a hydrogen gas explosion and blinding with acid. With larger solar arrays (>100 watt), people have even had fires with those too.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • hawaiianfishkeehawaiianfishkee Registered Users Posts: 11
    Re: Simple.. low watt solar pumping for water garden..

    thanks again for the input guys... i think i am going to continue my project unitl i get'er dun....and keep doing research.. i'm a very single track minded dude and i learned a lot so far.. before starting this project i didn't know the difference between a volt and amp... true indeed it is a learning experience, and i will continue to learn unitl i accomplish my goal... thank you all for baring with me on this one...:D i will keep you all updated..
  • hawaiianfishkeehawaiianfishkee Registered Users Posts: 11
    Re: Simple.. low watt solar pumping for water garden..
    BB. wrote: »
    You can add a regulator and/or a battery to stabilize the voltage and provide power when the sun is not usable.

    However, it adds complexity and costs. Also, batteries are very sensitive to how they are discharged and charged... Improper battery maintenance/operation can kill a battery in months, or even weeks.

    Solar + Charge Controller + Batteries is really great for off-grid power, but it doubles the cost/complexity of the system and you will get ~1/2 the power (for same solar panels).

    And adding batteries usually requires manual controller by the owner to make sure the batteries are not take to "dead" at night or in bad weather.

    It is certainly a learning experience. :roll:;)

    But, after a bit of work (and a lot of $$$), you will appreciate why we tell people to use utility power when available. It is much cheaper and easier to design and use.

    And don't overlook the danger caused by Solar PV and batteries. Even "car sized" 12 volt batteries are incredibly dangerous if not treated with respect. You can start a fire with overheated wiring or over charged battery. Or even have a hydrogen gas explosion and blinding with acid. With larger solar arrays (>100 watt), people have even had fires with those too.

    -Bill

    i don't really want to use a battery because of the reason you've mentioned... i just wanted a simple set up... run power when sun is up, and no power when sun is down..

    Hey Bill, what the difference between a regulator and a charge controller... i'm thinking they are the same thing??... i know that charge controllers are used for batteries so they dont over charge and seep reverse charge right? and a regulator basically regulates both voltage and amperage?.. and a linear current boosters exchanges voltage for amperes?
  • BB.BB. Super Moderators, Administrators Posts: 28,768 admin
    Re: Simple.. low watt solar pumping for water garden..

    A charge controller is a form of voltage (and current) regulator.

    A linear current booster can be a voltage regulator--but you are correct, its job is to take high voltage/low current from the array and "down convert" it to low voltage and high current for the motor...
    • Power = Volts * Current = Voltage-in * Current-in = Voltage-out * Current-out
    The electrical theory behind them is actually quite interesting. But not easy to say in a few words... Other than it is sort of the Electronic DC version of a variable AC Transformer (Variac).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • hawaiianfishkeehawaiianfishkee Registered Users Posts: 11
    Re: Simple.. low watt solar pumping for water garden..
    BB. wrote: »
    A charge controller is a form of voltage (and current) regulator.

    A linear current booster can be a voltage regulator--but you are correct, its job is to take high voltage/low current from the array and "down convert" it to low voltage and high current for the motor...
    • Power = Volts * Current = Voltage-in * Current-in = Voltage-out * Current-out
    The electrical theory behind them is actually quite interesting. Bot not easy to say in a few words... Other than it is sort of the Electronic DC version of a variable AC Transformer (Variac).

    -Bill

    hmmm.. i will read up on this a little more.. thanks Bill, more than helpful man..
  • hawaiianfishkeehawaiianfishkee Registered Users Posts: 11
    Re: Simple.. low watt solar pumping for water garden..

    hey i tried re wiring the panel to pump again today but i held the pump in one hand to see if anything changed.. when i connected the cables i heard the frequency sound and i felt the pump start to shake... i'm hoping that one more panel will do the job..
  • GreenerPowerGreenerPower Solar Expert Posts: 264 ✭✭✭✭✭✭
    Re: Simple.. low watt solar pumping for water garden..

    You are in luck that the motor you bought is brush-less DC. Those motors have electronics to drive the armature coils. For a 12V motor, the electronics usually shutdown the coil current driving when the applied voltage is below 8-9V (some could be as high as 10V). You could drive it with one panel you have, it just won't run at the rated RPM at full sun. What you need is a capacitor probably 100uF/50V parallel with the motor. When the motor is in "shutdown mode" the cap would be charged from the PV and when the voltage is high enough for the electronics to try to start the motor, the cap would give enough starting current i.e. torque to turn the rotor. Once the rotor is running, less current is needed to keep it running.
    GP
  • hawaiianfishkeehawaiianfishkee Registered Users Posts: 11
    Re: Simple.. low watt solar pumping for water garden..
    You are in luck that the motor you bought is brush-less DC. Those motors have electronics to drive the armature coils. For a 12V motor, the electronics usually shutdown the coil current driving when the applied voltage is below 8-9V (some could be as high as 10V). You could drive it with one panel you have, it just won't run at the rated RPM at full sun. What you need is a capacitor probably 100uF/50V parallel with the motor. When the motor is in "shutdown mode" the cap would be charged from the PV and when the voltage is high enough for the electronics to try to start the motor, the cap would give enough starting current i.e. torque to turn the rotor. Once the rotor is running, less current is needed to keep it running.
    GP

    Hey! This just keeps getting better and better!! :D so a 100uf/50v capacitor? hmmm… wouldn't the 50v just throw the whole thing off? Im going to try to do some research on this capacitor… Thanks Green!!
  • BB.BB. Super Moderators, Administrators Posts: 28,768 admin
    Re: Simple.. low watt solar pumping for water garden..

    50v volt is just the maximum voltage before the capacitor will fail.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
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