anyone happy with their dokio portable panels? i'm not...

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doublegregg

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so i've got my dokios set up, pointed south, optimal for the 1pm sun here in the bay area, angle is about 30 degrees, so pretty perpendicular to sun.. maybe i'm a little off. i never get more than 6 to 8 amps off the 300 w panels... i'm shorting them, taking current readings from that, to eliminate the controller, etc for my readings.

so - i'm figuring that's about all these can put out... give or take an amp or two. pretty disappointed. i guess i was hoping for mid teens in amps, for full sun, facing full on.

if i do the math, and i don't know how reliable the math is, they should put out up to ...well, 300w divided by 16 v, is 18.75amps... 

anyone else?
 
Fuzzy math but 13 amps (shorted panels) should happen in bright sunlight around noon with zero haze. 

This includes smoke, ocean haze, etc which will all cause a small or large drop in output. 

If the set is 'brandy new', did you remove the protective plastic film?
 
with 300 watts you should be getting at least 15 amps. I get 12 amps from 240 watts, and get 27 amps from 365 watts. But that is with an mppt controller. And these readings are with my panels flat on the roof.
If your only getting 6 to 8 amps, there is something wrong with your controller. What model controller do you have? If you have a quality mppt and your still getting 8 amps, either the panels are in parallel or you have voltage drop to the battery. Raising the bulk voltage might increase your amps to the battery.
300 watts / 14.4 amps = 20.8 amps which is the max you should get in the best conditions, example with a low battery and the sun overhead, in average conditions maybe 15 amps.
Dokio is a name brand panels they should at least produce what they are rated.
 
no plastic film on them... we do have some haze here, from fires in the sierras.., but i've been taking some readings for the past week or two. i'm just trying to find the maximum current coming from those panels by shorting the panel terminals, getting a reading with a dc clamp meter... thus eliminating the controller..  just the panels, pointed as much right at the sun as i can, a little wire to short the terminals, my meter.....

i try to do my reading when i figure the sun is at it's uh... peak? about 1pm.  if i never get a reading above 8 amps or so, i guess i'll resort to trying to block out some of the four panels... maybe one isn't uh,.. working? 

tx2sturgis said:
Fuzzy math but 13 amps (shorted panels) should happen in bright sunlight around noon with zero haze. 

This includes smoke, ocean haze, etc which will all cause a small or large drop in output. 

If the set is 'brandy new', did you remove the protective plastic film?
 
jonyjoe303 said:
with 300 watts you should be getting at least 15 amps. I get 12 amps from 240 watts, and get 27 amps from 365 watts. But that is with an mppt controller. And these readings are with my panels flat on the roof.
If your only getting 6 to 8 amps, there is something wrong with your controller. What model controller do you have? If you have a quality mppt and your still getting 8 amps, either the panels are in parallel or you have voltage drop to the battery. Raising the bulk voltage might increase your amps to the battery.
300 watts / 14.4 amps = 20.8 amps which is the max you should get in the best conditions, example with a low battery and the sun overhead, in average conditions maybe 15 amps.
Dokio is a name brand panels they should at least produce what they are rated.
i've been charging with an epever controller... at my stix and brix, so i got tools, good spot to place my panels, it's really stable. with the controller, it never goes above 7 or so amps. i should say the epever lists current for battery and panel on its display --- i really don't no which means what, but neither goes much above 8.

so that's why i decided i need to know how much current these dokio put out under optimal conditions, no controller ---so i pointed them right at sun, 1pm, full on, inclined around 30 degrees. i short the terminals of the panels - i get a reading of 8.3 amps or so... it is a little hazy here --- from fires, but idk if that would reduce the current in half...........??  

i assumed dokio's would be popular here, altho most questions seem to be on the newer portable power stations........
 
What is the condition of the battery? if its full or nearly full, you won't get much amps out of the panels. To get maximun amps the battery has to be under 13 volts while charging, the closer it gets to 14.4 volts the less amps go to the battery.
If the voltage is low around 13.4 volts and amps are low, it might be on float mode.
If you know the battery is depleted and your still getting 8 amps, try raising the bulk voltage on the controller and see if that helps. With voltage drop sometimes the controller thinks the battery is full and switches to float too early. If the controller reads 14.4 volts but the battery terminals only read 13.8 volts (battery not fully charge) the controller thinks its a fully charge battery and reduces amps.
On my 220ah lifepo4 14.6 volts which I rarely drain too much, the panel rarely puts more then 8 amps into it, on my 312ah li-ion 12.6 volt battery when its low can get the full 27 amps. The larger the differential between battery voltage and charge voltage, the more amps the battery gets.
A lead acid that isn't in great condition will charge up quickly to 14.4 volts and then won't take max amps from the panels.
I think the condition of the battery has more to do then the haze in the sky. Even when its overcast I can still get up to 15 amps from my 365 watt panel.
 
doublegregg said:
so i've got my dokios set up, pointed  south, optimal for the 1pm sun here in the bay area, angle is about 30 degrees, so pretty perpendicular to sun.. maybe i'm a little off. i never get more than 6 to 8 amps off the 300 w panels... i'm shorting them, taking current readings from that, to eliminate the controller, etc for my readings.
How many panels?  
How many watts each?
Vmax each?
Panels connected in series or parallel?

Panels should be tested individually (not connected together).
You need to know both the open circuit voltage and short circuit amps to determine output of each panel.
 
I'm curious about these panels as well. I have an epever controller. When you click the button to cycle thru the displays you'll eventually pass one that says something like 117 then 2n (these are code numbers regarding your "load" settings) after you pass that you'll see a number of volts then a number of amps. Then I believe X.X KWh then a number of volts again and a number of amps then X.XKWh then the load settings again.

The first voltage you see is solar panel voltage. For example mine in full sun is about 42ish volts then amps from solar about 4 if I'm getting 150-160 watts from my panels. Then the second voltage you come across is battery voltage XX.Xv then the amount of amps to the battery.

I'm wondering if you're looking at the solar input amps at the controller which will be relatively low especially if you're wired in series. Secondly as spiff said if they're still connected in series then those same amps are what you would see from the multimeter.

So my voltage is higher because I have 2 "18v" panels in series but they actually output around 20-22 volts so 22+22=44 I normally see around 42 40 36 maybe depends on a lot of factors. The MPPT controller is going to convert the voltage to what the battery needs supplied to it.

So I have 200 watts of panels. 22ish volts each wired in series for 44ish volts. 200w÷44v=4.545454A

But then at the battery if all 200 watts were available and the battery would accept a charge that high I would see something like 13vX15.38A= 200ishW

So I'm thinking maybe you're measuring their amperage at the higher voltage in which case the amps would be lower, but volts X amps = watts.

Remember the panels are a higher voltage than the battery by design. A 12 volt panel isnt going to charge a 12 volt battery. Especially as that battery will need to reach around 14.4 volts before its fully charged.
 
Spaceman Spiff said:
How many panels?  
How many watts each?
Vmax each?
Panels connected in series or parallel?

Panels should be tested individually (not connected together).
You need to know both the open circuit voltage and short circuit amps to determine output of each panel.

here are the specs --- i think...  i tried shorting the panels, as i said, in full sun... i do not get over double digits in amps. also people seem to say that shorting panels, as i'm doing with a short piece of wire, is a dumb-*ss thing to do................ there are four panels. it's a portable folding unit.... i'm guessing they are parallel... and are all 12 v panels.... but i'm guessing. this is frustrating - kind of guessing what my controller is doing.... 


Model:FFSP-320M
Material:Monocrystalline silicon
Maximum Power(Pmax): 300W±3%
Maximum Power Voltage(Vmp):18.00V
Maximum Power Current (Imp):16.67A
Open-Circuit Voltage (Voc): 22.50V
Short-Circuit Current (Isc):16.92A
Nominal Operating Cell Temp.(NOCT):-45 to 80℃
Maximum System Voltage: DC1000V
Foldable Dimension:39.37x19.69x0.94(in)/100x50x2.4(cm)
Expansion Dimension:78.74x39.37x0.24(in)/200x100x0.6(cm)
Net Weight:7.1kg
Package Weight:8.2kg
Package Size:108x57x7cm
Package List:
1*300W Flexible Foldble Solar Panel
A total of 4M long cable. With alligator clips.
1*20A 12Vcontroller
1*English User Manual


(The above data is based on the laboratory standard test environment)
For field connections,use minimun No.12AWG copper wires insulated for a minimum 90℃

Standard Test Conditions:
AM=1.5 IRRADIANCE=1000W/m2 Temp.=25℃
(The size is manually measured and there is a certain error.)
Controller support 12V lead-acid,lithium ions and LiFePO4 battries.
 
XERTYX said:
I'm curious about these panels as well. I have an epever controller. When you click the button to cycle thru the displays you'll eventually pass one that says something like 117 then 2n (these are code numbers regarding your "load" settings) after you pass that you'll see a number of volts then a number of amps. Then I believe X.X KWh then a number of volts again and a number of amps then X.XKWh then the load settings again.

The first voltage you see is solar panel voltage. For example mine in full sun is about 42ish volts then amps from solar about 4 if I'm getting 150-160 watts from my panels. Then the second voltage you come across is battery voltage XX.Xv then the amount of amps to the battery.

I'm wondering if you're looking at the solar input amps at the controller which will be relatively low especially if you're wired in series. Secondly as spiff said if they're still connected in series then those same amps are what you would see from the multimeter.

So my voltage is higher because I have 2 "18v" panels in series but they actually output around 20-22 volts so 22+22=44 I normally see around 42 40 36 maybe depends on a lot of factors. The MPPT controller is going to convert the voltage to what the battery needs supplied to it.

So I have 200 watts of panels. 22ish volts each wired in series for 44ish volts. 200w÷44v=4.545454A

But then at the battery if all 200 watts were available and the battery would accept a charge that high I would see something like 13vX15.38A= 200ishW

So I'm thinking maybe you're measuring their amperage at the higher voltage in which case the amps would be lower, but volts X amps = watts.

Remember the panels are a higher voltage than the battery by design. A 12 volt panel isnt going to charge a 12 volt battery. Especially as that battery will need to reach around 14.4 volts before its fully charged.

idk what you're asking,....  these are my first panels. i liked that they were portable and had a lot of power... in theory. my epever doesn't seem to match the settings you're saying --- i have the Tracer Bn series...
 
jonyjoe303 said:
What is the condition of the battery? if its full or nearly full, you won't get much amps out of the panels. To get maximun amps the battery has to be under 13 volts while charging, the closer it gets to 14.4 volts the less amps go to the battery.
If the voltage is low around 13.4 volts and amps are low, it might be on float mode.
If you know the battery is depleted and your still getting 8 amps, try raising the bulk voltage on the controller and see if that helps. With voltage drop sometimes the controller thinks the battery is full and switches to float too early. If the controller reads 14.4 volts but the battery terminals only read 13.8 volts (battery not fully charge) the controller thinks its a fully charge battery and reduces amps.
On my 220ah lifepo4 14.6 volts which I rarely drain too much, the panel rarely puts more then 8 amps into it, on my 312ah li-ion 12.6 volt battery when its low can get the full 27 amps. The larger the differential between battery voltage and charge voltage, the more amps the battery gets.
A lead acid that isn't in great condition will charge up quickly to 14.4 volts and then won't take max amps from the panels.
I think the condition of the battery has more to do then the haze in the sky. Even when its overcast I can still get up to 15 amps from my 365 watt panel.
hi jonyjoe
i actually have battleborne.  it's frustrating trying to guess what my controller, an mppt, is conjuring for my battery... i'd really like to just know how much my panels can put out right at midday, facing the sun, etc. etc... seems hard to do. so that leaves baby sitting my controller and battery, for a few days, since it's charging at around 6 amps. 
maybe when i plot out the numbers they'll make sense............ that would be a surprise. one thing i can't figure out is, my display for my epever has a panel and a battery voltage and amps. i really don't know why the double set of values.....................
 
any thoughts on this article? it seems to say it's ok, and useful info, to get the current flow of shorted panels... that's exactly ---  i think --- what i've been trying to do... and had people say that that is a bad idea...     but i don't follow much of the rest of this article over my head...

https://electronics.stackexchange.com/questions/18092/solar-panel-short-circuit

it's super frustrating for me, a newbie, admittedly, to be trying to read the mind of my charge controller..................i'd prefer to eliminate the thing, and just get some hard numbers from my panels themselves, and an ammeter. that number to my mind should be a ball park number of what my panels can do at a certain time of day, etc... that's what i need.
 
I checked the reviews on the dokio's 300 watt panels and the reviews are good. With mppt one user got 15 amps, I would take that as the minimum your panel should produce in the real world use. As long as the panels are producing voltage I would just hook it back up to your controller. The dokios are made up of 4 different solar panels connected together that might be a reason why the short circuit test isn't reading right.
Since you are using lifepo4 (battleborn) those batteries always read 13.1 volts, with voltage drop it won't take much to get the controller to go into float. The battleborn will easily take max amps all the way till it reaches 14.4 or 14.6 (whichever setting you use) but only if the charge voltage is high enough.
With my ecoworthy 20 amp mppt, when I had the bulk set to 14.6 volts, the battery was charging at about 4 amps. I had to raise the bulk voltage to 15.5 volts to get the controller to charge at 12 amps.
Something you can do is while charging put a heavy load on the system, from 8 amps it will go up to as high as the panel can provide. If it does, then that is a good indication the controller bulk voltage setting is too low.
When I see a problem of panels not producing max amps, voltage drop is the first thing I would check especially with lithium, those batteries will take every amp your panel will produce.
When I switched from lead acid to lithium I was also disappointed that my panel wasn't producing enough amps, I eventually troubleshooted to voltage drop.
 
jonyjoe303 said:
I checked the reviews on the dokio's 300 watt panels and the reviews are good. With mppt one user got 15 amps, I would take that as the minimum your panel should produce in the real world use. As long as the panels are producing voltage I would just hook it back up to your controller. The dokios are made up of 4 different solar panels connected together that might be a reason why the short circuit test isn't reading right.
Since you are using lifepo4 (battleborn) those batteries always read 13.1 volts, with voltage drop it won't take much to get the controller to go into float. The battleborn will easily take max amps all the way till it reaches 14.4 or 14.6 (whichever setting you use) but only if the charge voltage is high enough.
With my ecoworthy 20 amp mppt, when I had the bulk set to 14.6 volts, the battery was charging at about 4 amps. I had to raise the bulk voltage to 15.5 volts to get the controller to charge at 12 amps.
Something you can do is while charging put a heavy load on the system, from 8 amps it will go up to as high as the panel can provide. If it does, then that is a good indication the controller bulk voltage setting is too low.
When I see a problem of panels not producing max amps, voltage drop is the first thing I would check especially with lithium, those batteries will take every amp your panel will produce.
When I switched from lead acid to lithium I was also disappointed that my panel wasn't producing enough amps, I eventually troubleshooted to voltage drop.
hi jonyjoe
i don't think i have voltage drop... using 10 gauge marine wire, 20' round trip  panels to controller... i'm careful to have a secure connection in the epever terminals, which are pretty sturdy. i'm using romex copper wire for the controller to battery --- it's just for temporary purposes... that distance is 2 feet. i'm just charging out in my backyard. thanks for checking on the dokios reputation... nice to no...

i've set up the profile for the BB's, chiefly from their site. i think they're correct. since i'm new to this, i guess at this point i'm just trying to charge my battery, which will take a few days, since i typically only set it out for four hours a day. i may try to set it out earlier in the day. i'm simply pointing my panels south, inclined at about thirty degrees. 

it would be nice to get a clear answer on this shorting the panels, whether it is accepted practice or not, safe, etc... i much prefer isolating components to test them, not test them in a system. that just seems like guesswork and a pita. but, i'm a newbie at this....
 
As said previously if your batteries are near full
they won’t take the full charge. Another way to test this is to put a substantial load on and see if that bumps your amps.

Not sure how you test each panel with that setup, but you should do so - as well as the wiring at every step.
 
I think Mattie Van Halen moved on from his dokio panels to non flexible panels.
 
RVTravel said:
I think Mattie Van Halen moved on from his dokio panels to non flexible panels.
Oh dokio are flexible? I thought that was the German made rigid brand. Sorry I'm out of high speed data and low speed is sub snail pace at the moment or I'd look it up myself.

I spent way too much on a 25 watt flexible panel once that eventually melted while charging via a QC 3.0 15 watt USB bank port.

I have zero faith in flexible panels as a result. Also they're difficult to remove OEM connectors so I cannot in good conscience reccomended flexible panels except in limited circumstances. 

I was planning on using my 25 watt flexi panel to make a solar backpack for hiking.
 
Spaceman Spiff said:
There are a lot of solar panel testing instructions on the internet.  Find one you like -or- contact dokio for instructions.

Here's one:
https://www.lensunsolar.com/blog/how-to-use-multimeter-to-measure-volts-and-amps-of-solar-panel/
yes, there are a lot of solar panel testing examples on the internet... my OP was really about what your link says to do. i was just questioning because people, here, at least how i was interpreting it, were saying i needed a load to test my panels. also, in another thread, one person said shorting out the terminals on a panel was a REALLY bad idea.............

so the whole thing seemed confusing. i thought i was being pretty clear - i just want to be able to test the panel --- as a component --- and see if it was working okay... hence the short circuit current test.

i feel there's a lot of confusion about this test.
 
doublegregg said:
 in another thread, one person said shorting out the terminals on a panel was a REALLY bad idea.............

Please disregard that advice...it is incorrect (or a simple mistake) and I even posted a correction in that other thread.

To test the amps a solar panel can put out at your location in your level of sunlight, in other words maximum current (more or less), you will need to short the panel thru an ampmeter. This is not a 'bad idea', it is the way it is done. 

In fact the ISC rating on the panel label means: I (which means current) Short Circuited.
 
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