₦airaland Forum

odimbannamdi:
My Oga,

I have one (60v variant) on ground now that i may not use until about 2 months time. If you make me a decent offer, i may just let it go

How much?

NiyiOmoIyunade:
My intent may have been lost in all the English I spoke.

LFPs are not as standardised in series config and voltages as you may think or even as lead acid generally are. So lead acid you typically have 2v, 6v, 12v nominal and you can stack them as you choose.

Pylontech and Dyness are usually 48v nominal batteries but are arranged as 15s. This is very key as it means not every inverter can integrate well with them.

A Pylontech battery will not start balancing until cell voltages cross 3.45v per cell so you need to pass that threshold especially if you do deep discharges. Simultaneously the BMS freaks out at exactly 3.6v per cell which is 54v nominal and immediately shuts down the battery. So you can't charge to the max limit as you are BMS restricted.

The Felicity is more standardised for use with any run of the mill inverter.

In my book, Bulk charging is a Constant Current phase while Absorb and Float are both Constant Voltage phases. All these standards were speced before solar charging became mainstream. A mains powered charger would put out a constant current (bulk) till absorb voltage setpoint was reached and then start throttling current to maintain a constant voltage for X hours or till a tail current limit was reached and then go to float (another constant voltage phase).

The highlighted is smart as it gives room for more inverters to be compatible with charging and handling it's LVD though at the expense of 1s short in capacity. Not a bad trade off

adrusa:
My banks are also kept at 55V or 3.44v/cell, (Bulk, absorption and float).

Right, though no absorption in my setup, but when mine hits full, I throttle down my float to 3.375(27v) thanks to node red and mqtt. Don't want it sitting on float at 27.6v

NiyiOmoIyunade:
You probably want to spec 27v in terms of the individual cell voltages.

My Pylontechs are 15s for a nominal 48v system. If I extrapolated 27v, I would be doing 54v which would definitely trip the HV alarm on my battery bank.

I say so because many people will read and use this information.

Now all LFPs are not created equal - most are even silent about Float voltage e.g in the Victron + PylonTech integration, Victron is overriding the Pylon BMS to do 52.5v (3.5v per cell) constant voltage whereas the BMS is asking for 53.5v (3.57v per cell) and there is no voltage reduction at any time. So in an ongrid or ESS type system the batteries would sit at a constant 53.5v per BMS request or 52.5v if using Victron DVCC.

For the Felicity LifePO4, they run a 16s system and it seems the recommended voltages are rather high at 57.6v - 57.8v (3.6v per cell). And they spec no float as well).

Beyond the obvious decay that starts at high cell voltages, one wonders what is an optimal voltage to play at and how long it is safe to stay there, it is key to spec the Lithium voltages on a per cell basis or if you must quote voltage for the bank, spec how many cells are in series else people would make expensive mistakes.

I am referring to lifepo4 (LFP) and all of them are equal in nominal voltage of 3.2v and are rated to be charged at up to 3.65v without an immediate damage of cell. They are also equal in number of cells that makes up battery banks 4s, 8s, 16s for typical inverters 12v, 24v, 48v respectively. So the pylons, Felicity and the DIY will have those characteristics in common. The BMS then makes the difference in low and high voltage cut offs.

All LFP are not supposed to be floated(they are CC-CV) hence no mention of such in spec, but there are still several inverter built for lead acid that we are trying to adapt for lithium charging.

Charging an LFP at 3.4v max has just about 1 or 2% less capacity compared to charging at 3.6v so I personally don't see the motivation for charging at high voltages and consider 3.4v to be an optimal charging point. However in a solar environment where one needs to get as much juice within a short window sticking with 3.4v won't be good enough so I push mine a little further to 3.45v max.

ceaser:
Not around now but I'll inform 'em to have that addressed. Thanks.

But what about Li-on 18/65/0s, can that be ok float at the max recommended voltage (4.15v)?

Hmm.... considering that li-ion quite volatile then LFP I would expect that setting it high would have impact as well.

The CC has dedicated lithium charging settings but the voltages are user editable. Lead acid battery settings has bulk and float settings. But the moment you select Lithium charging profile, the bulk and float becomes redundant and you will be required to set the highest charging voltage. I'm now not sure if that voltage keeps it in float, but what I know is that if full, it remains at that set voltage until the sun retires for the day.

With lithium profile it should stop charging and trickle charging will not be happening, though charging(bulk) at high voltages is also not a good thing either.

earthrealm:
i thought LFPS shudnt be floated at all, all form of charging should stop once battery is full.
is the cheap a,ss powmr cc capable of doing it successfully.

It should not be floated at all but some chargers don't have the option of not setting a float hence a lower voltage float is better. If powmr truly has LFP charging profile then no float is due

ceaser:
I know the seller you got this from.

He is the only one that includes a pair of MC4 connectors in his PowMr CC pack.

By the way, I recently experienced an unusual disheartening performance form the use of this CC in its use with LFP. Although it was later addressed and the problem was just with one out of like 5 units I have worked with. So you may want to watch out for that.

Last time I used the CC with LFP, the problem started on the first day system went online. Panel config is 320 watts 2s2p on 24v105ah LFP, 1.5kva PSW inverter.

The inverter started acting up, switching off and on, and the digital meter reading on the battery begun to fluctuate from 29v to 32v, then back to 25v, to 29v and like that all over rapidly. The fluctuations also coincides with the inverter acting up. This problems is not reproducible when the DCB from panel to CC is flipped to off (when no charging current flows into the CC from the panels) or even the system is in use overnight/early mornings before the sun is high.

My conclusion then was that the CC was messing up by not being able to quickly throttle down and peg the inrush voltage and current to the user preset float of 28v once the battery gets full but goes as high as 30v and the BMS protect of the LFP kicks in to protect the battery by tripping off when incoming voltage gets to 29v; and because there is still a communication between the CC output and inverter input, the inverter too senses the voltage of 30v (its high voltage protect level) and switches off appropriately.

The solution was to reduce the float of the CC to 27.5v so that the battery when fully charged does not go beyond 27.4v at most. Everything has been working fine for about six weeks now.

This problem.did not happen with the other CCs in use and I even had to bring in a used PowMr I had lying around in the course of trouble shooting, but still couldn't recreate the scenario.

By doing that you have actually addressed another problem; floating LFP at high voltages is not good for the lifespan of the cells. I float mine at 27v

earthrealm:
My 4kva 48v mustpower inverter appears to have developed fault,

Intermittently the output flickers for several seconds and it will make violent sounds, the closest sound to it is the sound it makes when its trying to power a load wirh a huge surge, such as ac or sumo.

As this is happening, the cooling fan will turn on, and the load % display will flicker from the normal 10% it was to 30 or even 40% for a few seconds and then everything normalizes again.

This could then repeat again next 15mins or 30mins or 1hr.

I have disconnected the load, and observed it. It doesnt behave like that on zero load.

Does any body have an idea, what could be wrong.
It was deployed in 2016 and has served me wella Since

Have you considered that the issue may be external to the inverter? I suggest a gradual introduction of load to determine the load source that may be sending an occasional surge to the inverter

modgba:
Seplat Fumes After Access Bank Seals Lagos HQ Loan Default
https://businesspost.ng/economy/seplat-fumes-after-access-bank-seals-lagos-hq-over-loan-default/

Stock Investors Prepare for Implementation of 0.08% Stamp Duty on Trades
https://businesspost.ng/economy/stock-investors-prepare-for-implementation-of-0-08-stamp-duty-on-trades/

Asset Managers Mop up United Capital N15bn Commercial Papers at 1.26%
https://businesspost.ng/economy/asset-managers-mop-up-united-capital-n15bn-commercial-papers-at-1-26/

It’s Wrong for FG to Spend Investors’ Unclaimed Dividends—Lawmaker
https://businesspost.ng/economy/its-wrong-for-fg-to-spend-investors-unclaimed-dividends-lawmaker/

FG Threatens to Sanction DisCos Selling Prepaid Meters
https://businesspost.ng/general/fg-threatens-to-sanction-discos-selling-prepaid-meters/

SEC, SON Move to Stop Rejection of Nigerian Commodities Abroad
https://businesspost.ng/economy/sec-son-move-to-stop-rejection-of-nigerian-commodities-abroad/

They did?

Priscillar1234:
Thanks for the advice. Can you suggest a place where I can easily purchase the volt display from instead of having to order it from Aliexpress which will take quite a while

If all you need is a unit and you are in ado-ekiti you can grab the one I used in the past

ojeysky:
BMV 712 with 500A shunt, aux cable, long comms cable, temp sensor - 125k

12.8v 280AH LFP pack with 40A utility charger - 350k

Bus bars, 7s to 16s ANT BMS, 4s smart BMS, balancers(4s, 8s, 16s)

080-three 5-23-3535

The 2 units of the BMV at 200k for anyone paying within the next 24hrs

Priscillar1234:
Thanks for the response. What should I set the absorb voltage to and should I reduce the charge current to 20A or leave it at 30A?

30A is .2c I think that is fine, don't go above that though. As to absorb I don't have experience on that, wait for others who use that feature

Priscillar1234:
Good evening everyone. Kindly assist a new inverter user. Just got a 48v inverter system installed in my home by an inverter installer, but I would like to confirm the best charging settings for the batteries just to be on a safe side.
Please what should the charge settings be for the batteries in series 48v?
Bulk:
Absorb:
Float:
And which is better between 20A or 30A for charging the batteries through the inverter utility current?

modified: just incase you're thinking the batteries are installed on the floor, no there is a battery rack. I took the picture when it was just removed from the carton and placed on the floor during installation.

You could stay in the middle. Bulk 59.2 while float 54.8

Any user of the new MPP PIP-MAX in the room that can share their experience in it's performance?

olopan:
That's about right for both scenarios stated,

What I can't collaborate fully is the maximum power at lower voltage ....

but according to power law .... It's plausible.

I used the lowest voltage and maximum current to determine the maximum power that the device will consume. So depending on the TV settings at 100v it could require up to 2.1A but the current will be lower at higher voltage. In naija case where we use 230v(220-240) even if all the TV features are utilized 100%, the current won't be up to 1A thereby keeping power within the 210w max

odimbannamdi:
Guys, please how do i arrive at the wattage consumption of the TV in the first pic.

For the second one, does it imply the regular consumption is 135w?

For the first, operating range is wider hence I think the 2.1A is probably the maximum current at the least voltage of 100v which makes it 210w max

For the second 135w I expect is the maximum and 75w is the regular (typical).

Disclaimer: wait to get confirmation from the gurus on this, I may be wrong

Philipbbc:
I have to open a GTB account because of this international payment stuff, because i have only UBA and zenith which is $100 monthly limit.

Is GTB no longer limited to 100usd as well?

NiyiOmoIyunade:
Pertinent to note that voltage is not an accurate representation of state of charge and this is even more the case for most Lithium chemistries especially at partial state of charge.

I witnessed a Felicity Lithium pack go off at 50.2v after two days of low charge. One would have thought at least 30% capacity left at that voltage but the BMS tripped things off.

That happened due to cell imbalance, one of the cells got to the low cut off voltage of the BMS (usually 2.5v for LFP some set higher but below 3v) for a balanced cell pack, the voltage indeed does the indicate the battery SOC, it's more accurate with no load.

dapsyra:
Charging profiles differs across various Lithium chemistries. The chart is applicable to only LiFePO4 chemistry.

IYGEAL:
This would be helpful to me as well.

But is this true for all Lithium chemistries or just LFP?

Absolutely correct, I should have made that distinction, LFP was just what came to mind when the op asked

amdman:
2012 Toyota Camry (ex taxi)

No faults reported

280k miles

N2.5m

Looks like an hybrid?

ebocoms:
Good day everyone. Please I need Lifepo4 battery SOC chart for 24v just for reference. Mostly what i see online are for lead acid batteries. Kindly share if you have any. Thanks.

Find attached chart for 12v, multiply the voltage by 2 to make 24v. The chart is also why charging lithium at high voltages is not necessary.

Edit: The attached chart is for LFP chemistry

mank1234:
Did you actually discharge the 24V system to below 11V?
I thought lifepo4 cell is not expected to go below 2V.

Naa ignore the min voltage, it occurred when I needed to do some maintenance and disconnected first set of the cells from the BMS(ANT BMS), the BMV was fast to capture the voltage of the remaining cells before I disconnected the rest. Unfortunately there is no way to reset just a data point on BMV without resetting everything so I lived with it. The max voltage is also not what I use normally (I do 27.6v), there was an event to that as well

IYGEAL:
Interesting. Thanks a bunch.

A DIY guy is proposing to arrange a 200AH 12v LFP for me. And, considering the prevalent prices, I would say he's doing it on the cheap.

I wasn't sure if my 600W PV would be suitable to charge it until now. My scepticism was due to the massive PV you guys using LFP are amassing for your arrangements here.

I think this is to charge the battery faster and use the PV to power your loads so long as the sun allows?

Your CC appears to draw more power from PV than the capacity of the PV. While charging and simultaneously using my 200AH 12V quanta battery, the CC draws about 300+Watts from the 600W PV early in the morning, and about 150W later in the day, even when the sun would be said to be at peak.

Even 100w will charge it, but what is important is for how long. Since you have 600w PV, let's assume you are able to achieve 400w average harvest. That is 400÷12 which makes it about 33A charge rate @12v. 200÷33 will give you the number of hours it will take before battery gets full from empty.

NB: Those are theatrical calculations charge time can be +/- 60min

IYGEAL:
Thanks for your response.

Please can the second answer have an empirical example?

Charge and discharge efficiency of lithium is almost perfect; you get what you put in... attached is a full 14.3kwh LFP, notice the accuracy of the charge and discharge figures 20kwh (I did about 6kwh to full on BMV initially) is the difference and that has always been what I get at every cycle. In LA the difference will usually very and can be very significant in some cases

emmasoft:
There will be little or no impact positive or negatively in fact Unilever has operated more in years of border been opened than when border was closed.
Unilever stock will be affected basically by the state of the economy generally not on just a single act of opening border. The purchasing power of consumers is what should be of concern.
If you enter the stock at bottom price and ready for the long term nothing to worry about whether border open or not.

This being km13, looks like it's going to be a pretty long wait though

When you hit a sell with price limit on a stock instead of a buy and didn't realize until you got the contract note

mcTrinity:
1) Cells of PV Modules starts deteriorating once its exposed to sun...

2) how long have you used them?

Yes which is applicable to everyone but it does not get deteriorated faster because it's not in use

talk2tonie:
Morgan capital trading platform is very terrible. Not good for a newbie. I use them only to play around stocks.

Really? I guess I should stay with meristem then. I thought Morgan platform was okay

funshyboi:
Thanks bro, I’m talking about the lifespan of the solar panel not battery because I think since it’s exposed to sun electrons will be generated and the battery is lithium not lead. Pls what do you mean at the bolded

I knew you were talking about panel lifespan and I already adviced that it should not impact the lifespan. That said I have not reached or gotten close to the lifespan(25 years) of mine.

As to the highlighted, what I meant is that perhaps the cell is full and you don't have much load hence the reason harvest is low so increase your load to see if there is changes

Mcy56:
Access: 8.05
UBA: 7.90

If I were to buy, I will pick Access ahead of UBA.
Abeg make Una no mind me o, both are good..........not any form of advice.......DD applies.

Now UBA leading at 8:20....looks like both are husband and wife but I agree with access first if not for anything for dividends gain. The interim from UBA was lower than access

BrokerHaruna:
ETI
Guinness
Both are seriously undervalued.
Both will surprise many folks

Yeah it will happen but when is the major question though

funshyboi:
1. Good morning guys, does exposing panels to sun without connecting it to battery simply because I won’t be around for a while reduce it’s lifespan?

It shouldn't but you can just set a float voltage to check your battery at float(I assume it's lead acid). So don't disconnect it from charging.

2.the peak average amps the panels produces when i Just bought it is 9.0 amps but it hardly reaches 4.0 amps these days does anybody has an explanation for that, or what am I not doing right

Check the panel surface which may be dusty it's also possible you don't have demand (load). Finally there is change in the direction of the sunlight so depending on your panel tilt that may be the reason for lower yields as well