Somebody here once tried this - I think his NL moniker was @Sinistrian or so - he fed his Zinox hybrid's PV input with the output of another MPPT CC.

When I think about it and based on similar experiments I have tried using an MPPT CC to modulate the output of a manual battery charger, my conclusion is that an MPPT CC can take any DC input within it's voltage range - the issue is with the DC power source being able to handle a variable load as the CC varies its internal electrical profile (not sure the right term is 'resistance') to pull more or less current from the power source.

The DC power source feeding the MPPT input has to be able to

1) Generate and sustain the required MPPT operating voltage

2) Tolerate the maximum current draw the MPPT may impose from time to time (current limiting ability inside the MPPT may be desirable)

3) Tolerate the very variable load profile the MPPT will present as it sweeps to find a sweet spot.

Trippledots:
@chris @niyiomolyunade and other DIYers

Can an mppt controller be fed with a regulated DC supply? I have read conflicting ideas on how it will perform. Some say the algorithms that mppt devices operate with may cause it to self-destruct or destroy the power supply. Others say it should work as long as the the power supply has some current limiting feature in it's design.

There isn't any practical video or article about it i could lay my hands on.

So what dyu guys think?

And anyone who has an mppt controller that they don't mind sacrificing for science I'll like to see a practical demonstration of such connection. I dnt mind collecting and carrying out the experiment myself if the donor prefers it that way.

mank1234:


There are cheap mppt controllers on aliexpress. You can get one and try, if no one is willing to donate.

Yeah, thats a point. But the few "cheap" ones i know of seem to simply do a buck or conversion. I'm not so certain their mppt algorithms are shock proof like more expensive ones_maybe anyone willing to join spare cash with me to purchase one should indicate....Learning new stuffs gives me a special kind of high, but cash is limited jare.

Talking abt the cheap ones tho, I'll appreciate a link to check and see if its within my pocket's reach.

Thanks for the input bro... �

NiyiOmoIyunade:
Somebody here once tried this - I think his NL moniker was @Sinistrian or so - he fed his Zinox hybrid's PV input with the output of another MPPT CC.

Really? I'll go look for him

When I think about it and based on similar experiments I have tried using an MPPT CC to modulate the output of a manual battery charger, my conclusion is that an MPPT CC can take any DC input within it's voltage range - the issue is with the DC power source being able to handle a variable load as the CC varies its internal electrical profile (not sure the right term is 'resistance') to pull more or less current

Nice... This is basically the kind of info i need. What do you mean by manual though?

Tolerate the maximum current draw the MPPT may impose from time to time (current limiting ability inside the MPPT may be desirable)

Very true this. I am thinking a fuse rated at about half the current rating of the charger should do the trick incase the mppt wants to pull too much current. What dyu think?

The DC power source feeding the MPPT input has to be able to

1) Generate and sustain the required MPPT operating voltage

2) Tolerate the maximum current draw the MPPT may impose from time to time (current limiting ability inside the MPPT may be desirable)

3) Tolerate the very variable load profile the MPPT will present as it sweeps to find a sweet spot.

Thank you so much for your incisive input always egbon.

A manual charger - those basic ones that simply feed an AC waveform through a rectifier circuit to produce DC voltage.

Manual because they are not smart and have no DC regulation or cutoff - they simply keep putting out a fixed voltage and current into the battery so you have to manually terminate the charge once you have determined the battery is fully charged else battery go swell.

I had one of those and used an MPPT CC to regulate the output voltage of the charger - sort of to simulate a regulated 3 stage charge - I cannot say for certain how well it went as I quickly determined that the battery I was trying to salvage was beyond repair and ended the experiment.

I do remember though that a PWM CC I had did not even pass through the voltage to battery when I connected the manual charger to the PV input of the CC.

Trippledots:


Really? I'll go look for him



Nice... This is basically the kind of info i need. What do you mean by manual though?



Very true this. I am thinking a fuse rated at about half the current rating of the charger should do the trick incase the mppt wants to pull too much current. What dyu think?



Thank you so much for your incisive input always egbon.

So curiosity get the better of me eventually and i have my answers now..

Armed with niyiomolunade s reply i
1. Took a laptoolp power supply rated at 24v/2.5A
2. Using a clamp i momentarily shorted the output to see how the adapter itself behaves in a dead short. I noticed it simply cuts supply once amps reaches about 2A for about 1sec then resumes again. Repeating the same process if the same condition persists.

3. Armed with this new information, i connected the laptop charger to the PV input of my expensive fangpusun 100v/30amps mppt controller.

Result

Controller mppt control showed battery charging at 13.3v/ 5-6A.

Since the laptop power supply is rated at about 2A, it was apparent the mppt was doing a buck conversion and charging the battery.

So my curiosity satisfied at last!

I love Science!

Next is to use a higher regulated I/V to feed the mppt controller and see what happens as it tracks that mpp.

Cheers.

NiyiOmoIyunade:
A manual charger - those basic ones that simply feed an AC waveform through a rectifier circuit to produce DC voltage.

Manual because they are not smart and have no DC regulation or cutoff - they simply keep putting out a fixed voltage and current into the battery so you have to manually terminate the charge once you have determined the battery is fully charged else battery go swell.

I had one of those and used an MPPT CC to regulate the output voltage of the charger - sort of to simulate a regulated 3 stage charge - I cannot say for certain how well it went as I quickly determined that the battery I was trying to salvage was beyond repair and ended the experiment.

I do remember though that a PWM CC I had did not even pass through the voltage to battery when I connected the manual charger to the PV input of the CC.

Oh ok.... I get that now.


Interesting. I have been using a cheap pwm with a battery of laptop chargers to charge my battery for months now. It did charge the battery, but i noticed when the battery got to float, it still allowed a sizeable amount of current to pass through to the battery. Since power supply here is very epileptic i didn't bother about it since i would be lucky if the battery hit float before we had a power cut.

Please who has an idea of what the low voltage cut-off of a 12 volt luminous hybrid inverter would be?

Dishtech:

I think that ur battery has BMS in it. Just don't charge above 14.6volt are good to go.

Well, BMSes fail over time. They are presumably designed to last the lifetime (or a little more) of the batteries they come packaged with.

Now if you get these components from different suppliers and have them working together in incongruence and their individual lifetime gets spent one before the other; you know what that means.

Penuelseun:
Lifepo4 batteries are now in stock. Tested and confirmed 40ah with charger

used or brand new??

that vinpower inverter, u sampled there?. how is your serving you?, does the fan come on at all??.
i bought a 1kw unit from a vendor here, it barely lasted 3wks, and gave up ghost, vendor told me verbal sorry

generationz:

Thanks.


Is the inverter needed for the solarbpanel or powerbank?

Considering the fact that I can use the power bank to charge my phone and laptop without an inverter on a normal day when it was charged with electricity.

I need a good power bank for charging my laptop. Which one do you use, or can you recommend?

Wow... Fangpusun is a solid mppt controller.
Two laptop power supplies have paid the ultimate price for science tho

This controller is sha solid so far; does true mppt tracking.

hausadreturn:
I need a good power bank for charging my laptop. Which one do you use, or can you recommend?

I recommended one for someone who contacted me some weeks back. Its one of these lithium packs, and the person hasn't given me a complete feedback. But i think its working because if e no work e for don knick my door tey tey.

hausadreturn:
I need a good power bank for charging my laptop. Which one do you use, or can you recommend?

I use the xtreme 105,000 mah
Check jiji
Although I'll adviceif you can afford it you get a mini solar set up not more than 8ok

Trippledots:


I recommended one for someone who contacted me some weeks back. Its one of these lithium packs, and the person hasn't given me a complete feedback. But i think its working because if e no work e for don knick my door tey tey.

Which one?

generationz:



I use the xtreme 105,000 mah
Check jiji
Although I'll adviceif you can afford it you get a mini solar set up not more than 8ok

How much is the xtreme 105,000mah, and where did you buy it?

Trippledots:


I recommended one for someone who contacted me some weeks back. Its one of these lithium packs, and the person hasn't given me a complete feedback. But i think its working because if e no work e for don knick my door tey tey.

What's the name?/

olatade:
Please who has an idea of what the low voltage cut-off of a 12 volt luminous hybrid inverter would be?

11v to 10.5v

hausadreturn:
How much is the Xtreme 105,000mah, and where did you buy it?

I contacted someone on Jiji
I bought it last year for 29k

It should be almost 4ok now.

hausadreturn:
How much is the xtreme 105,000mah, and where did you buy it?

I can give you a better one for 12k

Penuelseun:
I can give you a better one for 12k

Let me see pictures.

generationz:


I contacted someone on Jiji
I bought it last year for 29k

It should be almost 4ok now.

Let me dm you. Check your mail.

12volts or 24volts inverter? Which one is better? Gurus in d house please help

hausadreturn:
Let me dm you. Check your mail.

Sorry, I only reply mails from here that are work related for which I provide my mail or phone number.

Please, ask your question here. Thanks.

idris4r83:
12volts or 24volts inverter? Which one is better? Gurus in d house please help

It depends on the application and type of inverter and battery configuration
But speaking generally, a lower voltage setup like 12v is usually for light load and small system since all you may require may just be a single 12v battery. Whereas 24v system requires a minimum of two batteries. So both are ok dependent on what you want to achieve.

Sir George, thank you so much

GeorgeD1:


here's a rough depiction of what i have on ground. please never mind the hand drawing.
replicate that in 3 places to represent each of the three strings and connect each string
to a single bus bar. so i have 3 positive cables and three negative cables connected to
my inverter through the bus bar. and very importantly, each cable having equal length
regardless of distance from battery bank. so essentially, it's three independent banks
operating as one. same charge current, same discharge current from each string.
hope this helps?

olatade:
Please who has an idea of what the low voltage cut-off of a 12 volt luminous hybrid inverter would be?

10.6volt.
I designed a small system for low voltage cutoff using my PWM CC which I can set the required voltage cutoff. For me I don't want to go below 12.1 voltage.

hausadreturn:
Let me see pictures.

Here

generationz:



I use the xtreme 105,000 mah
Check jiji
Although I'll adviceif you can afford it you get a mini solar set up not more than 8ok

What will be the specs of the components of this solar setup costing not more than 80k?

Dishtech:

10.6volt.
I designed a small system for low voltage cutoff using my PWM CC which I can set the required voltage cutoff. For me I don't want to go below 12.1 voltage.

Mind sharing how you achieved this?

BetaTechnicians:

Mind sharing how you achieved this?

/quote]
I have been trying to post the image but unsuccessful, I will draw the schematic diagram and post later.

Dishtech:

/quote]
I have been trying to post the image but unsuccessful, I will draw the schematic diagram and post later.

Ok

I used this with a 24V dc-coil AC contactor to disconnect a specific load at a particular battery level. though I had to pass it's output through a dc buck to make the output a constant 24V for the contactor.