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few questions about solar power....

robbob2112 said:
Lemme save you 23 pages of reading -

He has a 30amp PWM controller and as of last I knew he had 3 x 50watt 12v (18.x VOC) panels connected in parallel. He can add a 4th 50w pannel to the other 3 and use the extra power. Each puts out a max of 4.2 amps.
50w * 4 panels * 0.7 for efficiency of pwm = max watts in of 140watts power in

140w / 14.2v (charge voltage)= 9.85amps

He has 2 x 12v 100ah AGM lead acid batteries in parallel - max charge current 11.2amps per so 22.4amps max we are 1/2 that or less

IF he respects the batteries he burns off 50% SOC - or 640Wh.

So - 640Wh / (9.8*12.8) = 5.1hours - that is how long at full sun he needs to fully charge his battery set. Now, I suspect he is running them to SOC of 20% or less. Basically until the inverter shuts off from low voltage. So it will probably take more like 8 hours of full sun to get a full charge.

Now - his crimps if you dig through and look at the videos and pictures are not good boardering on dangerous so I am sure there is heat loss there.

The inverter he had last time I saw it was labeled at 500w but performs more like 300w if that. He has several others unless they are gone that are 1000w labels or more, but are probably 100w inside.

It has been suggested multiple times he switch to LFP battery and/or to a MPPT as well. Both scare him and/or cost to much money to save up at one time (12000ish pesos each)

Now you have a good starting point and understanding of what he has.
Click to expand...
minor correction i have 2x 12v 50ah linked in parallel...
the 100ah battery is sitting on the floor collecting dust until i can figure out how to bring it back to life...
 
corporal_Canada said:
minor correction i have 2x 12v 50ah linked in parallel...
the 100ah battery is sitting on the floor collecting dust until i can figure out how to bring it back to life...
Click to expand...
So, add a 50w panel in parallel with the others and you are maxed out without a new mppt and an additional battery
 
ThaiTaffy said:
Thanks alot!

So in other words a glutton for cheap unreliable components, maybe LFP should scare.

Corporal sorry but your using a solar setup minus the AC charger and inverter that I pretty much use to water my garden, learning is fair enough but I doubt your saving any electricity in reality by the losses from your ac charger and if your doing it for environmental reasons think of the e waste.

I know we get alot of power cuts so if you did it as a sudo UPS for your computer you would have been far better off not buying any inverters and just using a 12v Pico PSU and a cheap usb powered monitor.

Now onto the serious stuff,
Find a ground!!!! Otherwise the news in Asia will read "French Canadian found dead in apartment, likely wire fueled bdsm accident"
Click to expand...
agreed but me tampering with power lines inside the wall may lead to a similar newspaper article.. although, they just call foreigners "afam" here.. just as you are "farang" over there, please be mindful, my dad retired to Pataya and died of stomache cancer... might be the food. or a pissed off wife, who knows..
 
robbob2112 said:
Lemme save you 23 pages of reading -

He has a 30amp PWM controller and as of last I knew he had 3 x 50watt 12v (18.x VOC) panels connected in parallel. He can add a 4th 50w pannel to the other 3 and use the extra power. Each puts out a max of 4.2 amps.
50w * 4 panels * 0.7 for efficiency of pwm = max watts in of 140watts power in

140w / 14.2v (charge voltage)= 9.85amps

He has 2 x 12v 100ah AGM lead acid batteries in parallel - max charge current 11.2amps per so 22.4amps max we are 1/2 that or less

IF he respects the batteries he burns off 50% SOC - or 640Wh.

So - 640Wh / (9.8*12.8) = 5.1hours - that is how long at full sun he needs to fully charge his battery set. Now, I suspect he is running them to SOC of 20% or less. Basically until the inverter shuts off from low voltage. So it will probably take more like 8 hours of full sun to get a full charge.

Now - his crimps if you dig through and look at the videos and pictures are not good boardering on dangerous so I am sure there is heat loss there.

The inverter he had last time I saw it was labeled at 500w but performs more like 300w if that. He has several others unless they are gone that are 1000w labels or more, but are probably 100w inside.

It has been suggested multiple times he switch to LFP battery and/or to a MPPT as well. Both scare him and/or cost to much money to save up at one time (12000ish pesos each)

Now you have a good starting point and understanding of what he has.
Click to expand...
rumble.com

June 11, 2024

rumble.com rumble.com

Tiny problem, I am NOT receiving the 140watts that you think I am
 
Did you ever crimp your battery cable properly?

And I don't trust your power meter any more than your other equipment. What does the pwm say is passihg?
 
Stop buying the cheapest stuff available, it's junk. We live in Asia reasonable quality items are still a fraction of the price compared to the west.
Many westerners think Chinese goods are trash and your likely buying goods even the Chinese think are trash.
Buy yourself an aneng clamp meter they are extremely cheap on Lazada and fine for DIY use, this should at least give you some reasonably reliable numbers.

NB. Check the description on the clamp meters make sure it reads DC
 
Last edited:
robbob2112 said:
Did you ever crimp your battery cable properly?

And I don't trust your power meter any more than your other equipment. What does the pwm say is passihg?
Click to expand...
by pwm.. you mean fake mppt ?? no watts displayed.. just volts and a battery with a smiley face... umm. 13.1v
no change to any of the big cables.. just tightened but only 1 end of the 0 gauge cable really needs attention... i just need to head to a hardware store and fetch umm.. big ring terminals, i just need but 1...
 
ThaiTaffy said:
Stop buying the cheapest stuff available, it's junk. We live in Asia reasonable quality items are still a fraction of the price compared to the west.
Many westerners think Chinese goods are trash and your likely buying goods even the Chinese think are trash.
Buy yourself an aneng clamp meter they are extremely cheap on Lazada and fine for DIY use, this should at least give you some reasonably reliable numbers.
Click to expand...
i did press buyon a DC clamp meter.. it arrived being an AC clamp meter... but i will look out for aneng clamp meter.. thank you...
 
ThaiTaffy said:
Stop buying the cheapest stuff available, it's junk. We live in Asia reasonable quality items are still a fraction of the price compared to the west.
Many westerners think Chinese goods are trash and your likely buying goods even the Chinese think are trash.
Buy yourself an aneng clamp meter they are extremely cheap on Lazada and fine for DIY use, this should at least give you some reasonably reliable numbers.

NB. Check the description on the clamp meters make sure it reads DC
Click to expand...


I've bought some chinese stuff that is good, but with the way things are copied and made the cheapest it is virtually impossible for me to tell good from bad. Even price isn't a good guide.

Is that a cultural thing?
 
corporal_Canada said:
by pwm.. you mean fake mppt ?? no watts displayed.. just volts and a battery with a smiley face... umm. 13.1v
no change to any of the big cables.. just tightened but only 1 end of the 0 gauge cable really needs attention... i just need to head to a hardware store and fetch umm.. big ring terminals, i just need but 1...
Click to expand...
Yes, and they typically display volt and amps with the push of a button.
Watts = amps * volts
 
robbob2112 said:
I've bought some chinese stuff that is good, but with the way things are copied and made the cheapest it is virtually impossible for me to tell good from bad. Even price isn't a good guide.

Is that a cultural thing?
Click to expand...
No your likely getting reasonable quality gear in the west, here in Asia they sell really poor quality as it doesn't have to pass many standards.
These meters are literally $2 and can probably kill doing a current test.
Screenshot_20240612-195123.png
 
ThaiTaffy said:
No your likely getting reasonable quality gear in the west, here in Asia they sell really poor quality as it doesn't have to pass many standards.
These meters are literally $2 and can probably kill doing a current test.
View attachment 221530
Click to expand...


We get really poor stuff to, a store called harbor freight gives away a $2 meter with any purchase. The rest of their inventory is poor quality for very cheap. But I sometimes buy a tool there if I know I am only going to use it once.

When we say cheap Chinese junk it is because we want something that works as stated for a low price. Good example are bus bars, $40 for a pair with a stated rating of 250 amps. They are labeled as brass but if you meassure them and do the math they are only safe at 80amps. Run higher and the get way to hot.
 
robbob2112 said:
When we say cheap Chinese junk it is because we want something that works as stated for a low price. Good example are bus bars, $40 for a pair with a stated rating of 250 amps. They are labeled as brass but if you meassure them and do the math they are only safe at 80amps. Run higher and the get way to hot.
Click to expand...
Not even really available here in Asia as in even the brass is hard to find when you decide to make your own.
 
ThaiTaffy said:
Not even really available here in Asia as in even the brass is hard to find when you decide to make your own.
Click to expand...


Gotcha - and with brass the mix of copper/tin ratio determins the current carring capacity. More copper = more expensive = more current carrying capacity.


Since you are there, can you pick out a good LFP 12v50ah battery or even 100ah and a MPPT controller that looks real? Something for our french friend?
 
He shops on Lazada it's full of sinopy, CATL, CALB cells and Daly bms's. 12v 100ah would be about $120 then a 40amp 100voc epever is about $65
 
ThaiTaffy said:
He shops on Lazada it's full of sinopy, CATL, CALB cells and Daly bms's. 12v 100ah would be about $120 then a 40amp 100voc epever is about $65
Click to expand...
i do actually for the simplicity of the purchase, not sure if they have Gcash in Thailand but it is big here...
bought a 7 filter water filter earlier today.. got tired of paying for drinking water... 15-25 php for 10L... just filter city water.. it is alreafy full of chlorine...
 
dont know if i posted a video of that watt display sending 14watts while it wasnt connected to the mppt... i am going tommorow to return it.. i really need to know if im getting minimum 200 watts going INTO the power bank so that i can use my computer stuff without anxiety.. and naturally.. once this is all stable.. ill add more panels, batteries.. quality mppt and give life to my refridgerator.. and someday even my AC.. i dream of the day where electricity bill is nonexistant... and im looking online for an AIO of course but when i listed my demands.. this is an ECOflow btw... the base unit is 246,000 php.. and i need 4 panels that produce 420 watts.. each panel is 50,000.. so total is now the same price as a used toyota... 446,000 php... your thoughts ???
that is 7,600$us and 10.5 grand in Canada funny money...
 
corporal_Canada said:
dont know if i posted a video of that watt display sending 14watts while it wasnt connected to the mppt... i am going tommorow to return it.. i really need to know if im getting minimum 200 watts going INTO the power bank so that i can use my computer stuff without anxiety.. and naturally.. once this is all stable.. ill add more panels, batteries.. quality mppt and give life to my refridgerator.. and someday even my AC.. i dream of the day where electricity bill is nonexistant... and im looking online for an AIO of course but when i listed my demands.. this is an ECOflow btw... the base unit is 246,000 php.. and i need 4 panels that produce 420 watts.. each panel is 50,000.. so total is now the same price as a used toyota... 446,000 php... your thoughts ???
that is 7,600$us and 10.5 grand in Canada funny money...
Click to expand...
I just bought a AiO, battery, 2x400w panels and all the miscellaneous stuff for 40,000php total on lazada it runs all our lights,fans,a fridge,a server Rack and a desktop pc.
 
ThaiTaffy said:
I just bought a AiO, battery, 2x400w panels and all the miscellaneous stuff for 40,000php total on lazada it runs all our lights,fans,a fridge,a server Rack and a desktop pc.
Click to expand...

Sounds like you (the corporal) needs to cut back on the drinking a bit and save enough to order this kit.
 
robbob2112 said:
Sounds like you (the corporal) needs to cut back on the drinking a bit and save enough to order this kit.
Click to expand...
I honestly don't know where you could buy a single PV cell for as much as he's quoting maybe he mistyped 5,000 PHP as 50,000 a 600w longi is about 5000.
 
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