Need some advise regarding my first build.

[Johnyguy]

I regard these as high value (cheap but good) inverters with excellent surge capability and low efficiency (high idle drain AND low efficiency).

That unit likely burns 50W all the time, even when not powering loads. That's 1.2kWh/day - a notable chunk of the 560Ah capacity discussed. Unlikely to get more than 85% conversion efficiency on top of the high idle draw.

Something else to watch out for on these inverters when charging from AC...

They have ABSURDLY LONG absorption times, which is not good for LFP.

Their absorption TIME is based on 10X the time to charge to a voltage slightly below absorption. So if it takes you 30 minutes to get to absorption, it will spend 300 minutes (5 hours) at the absorption voltage.

Checked the manual:

If you have it set for Lithium, then the charge current is only 3.45V/cell with the same float. This is mostly okay, but you are signed up for a fairly long charge period.

yes it is draws 39W the victron draw 20W

so you saying it is not good for the battery if i use its charger function for my lifepo4 it would lower its life?
It can be turned off as well i did look
Any good inverter you can recommend in the 3000W ?
Thanks!!

this is for my 24 V 280Ah pack
Charger only turns on when battery reaches 21V

here is the manual for the Aims one but it is very similar

https://www.aimscorp.net/documents/PICOGLF1-6W%204821.pdf

Also regarding it's power saver mode it would bring down the power consumption to 19W but people say this can hurt some electronic this pulsating current.... Also cannot be used with a fridge

From the manual: Power Saver Auto Setting : The inverter is factory defaulted to detect load for 250ms in every 30 seconds. This cycle can be customized to 3 seconds through the SW3 on the DIP switch.

Would the power saving mode be useful?

Thanks for any input!

 

[sunshine_eggo]

yes it is draws 49W

so you saying it is not good for the battery if i use its charger function for my lifepo4 it would lower its life?

If you allow it to run through the absorption phase, yes.

It can be turned off as well i did look
Any good inverter you can recommend in the 3000W ?
Thanks!!

Victron Multiplus 24/3000

this is for my 24 V 280Ah pack
Charger only turns on when battery reaches 21V

here is the manual for the Aims one but it is very similar

https://www.aimscorp.net/documents/PICOGLF1-6W%204821.pdf

I looked at the manual on the Youtube you linked. It's Lithium setting is okay, but you're in for long charge times.

The AIMS is the worst. It will hold your battery at 3.6V/cell indefinitely. That's going to hurt your cells. If you manually terminate charging when you see the battery hit 3.6V/cell, it's fine.

The least harmful setting would be Gel if you don't want to watch it.

Also regarding it's power saver mode it would bring down the power consumption to 19W but people say this can hurt some electronic this pulsating current.... Also cannot be used with a fridge

Correct. It's like turning the AC on for a quarter second every 30 seconds. If you're just talking resistive loads like lights or heaters, no problem.

From the manual: Power Saver Auto Setting : The inverter is factory defaulted to detect load for 250ms in every 30 seconds. This cycle can be customized to 3 seconds through the SW3 on the DIP switch.

Would the power saving mode be useful?

Only if you truly use no loads of any kind. If you have ANY loads that need powering, it doesn't work.

 

[Johnyguy]

If you allow it to run through the absorption phase, yes.



Victron Multiplus 24/3000



I looked at the manual on the Youtube you linked. It's Lithium setting is okay, but you're in for long charge times.

The AIMS is the worst. It will hold your battery at 3.6V/cell indefinitely. That's going to hurt your cells. If you manually terminate charging when you see the battery hit 3.6V/cell, it's fine.

The least harmful setting would be Gel if you don't want to watch it.



Correct. It's like turning the AC on for a quarter second every 30 seconds. If you're just talking resistive loads like lights or heaters, no problem.



Only if you truly use no loads of any kind. If you have ANY loads that need powering, it doesn't work.

i know about the victron it is $1300
do you know the standby power of that unit ?

So the pulsing current would not work with a fridge or a descktop PC right?
but no harm to lights and heaters correct?

If i don't use the charging option and use it as an inverter than i guess it is ok unit? but would use too much standby power...
it is on sale for $655


Also it would only turn to AC power when the battery goes down to 21V in a 24 V setup is that too low ?
I am new to this as you can see

Thanks!!
Switch setting Description Boost / Vdc Float / Vdc 0 Charger Off
1 Gel USA 14.0 13.7
2 AGM 1 14.1 13.4
3 AGM 2 14.6 13.7
4 Sealed lead acid 14.4 13.6
5 Gel EURO 14.4 13.8
6 Open lead acid 14.8 13.8
7 Lithium battery 14.4 14.4
8 De-sulphation 15.5 (4 Hours then Off)

I think i have find the answer here :

24V LiFePO4 Battery w/ BMS

• Absorption: 29V
• Float: 27.2V
• Inverter Cut-off: 21.4V-24V

So the 21V is low and not good for the battery

 

[sunshine_eggo]

i know about the victron it is $1300
do you know the standby power of that unit ?

https://www.victronenergy.com/upload/documents/Datasheet-Multiplus-inverter-charger_2kVA-and-3kVA-120V-US-EN.pdf

20W

More efficient and can be easily programmed for a multitude of things.

So the pulsing current would not work with a fridge or a descktop PC right?

Correct.

but no harm to lights and heaters correct?

Correct.

If i don't use the charging option and use it as an inverter than i guess it is ok unit? but would use too much standby power...
it is on sale for $655

Perfectly fine, and you CAN use it for AC charging, you just need to configure it for GEL or watch it and cut the charger when the battery hits ~14.2-14.4.

Also it would only turn to AC power when the battery goes down to 21V in a 24 V setup is that too low ?

Some would say yes, but your cells can go to 20V (2.5V/cell). Furthermore, when connected to AC, the unit will not allow the batteries to discharge, but will keep them floated.

I am new to this as you can see

Thanks!!
Switch setting Description Boost / Vdc Float / Vdc 0 Charger Off
1 Gel USA 14.0 13.7
2 AGM 1 14.1 13.4
3 AGM 2 14.6 13.7
4 Sealed lead acid 14.4 13.6
5 Gel EURO 14.4 13.8
6 Open lead acid 14.8 13.8
7 Lithium battery 14.4 14.4
8 De-sulphation 15.5 (4 Hours then Off)

I think i have find the answer here :

24V LiFePO4 Battery w/ BMS

• Absorption: 29V
• Float: 27.2V
• Inverter Cut-off: 21.4V-24V

So the 21V is low and not good for the battery

Absorption is flexible. 3.55-3.65V/cell will get you very nearly fully charged the moment you hit that voltage. If you are patient, cells can get to 98%+ SoC at 3.45V/cell.

Float at 3.4V/cell is generally recommended. Battleborn allows for up to 3.45V/cell, so there's some wiggle room.

Programs 2 and 4 would also work, but the long absorption time is undesirable. If you're willing to watch the voltage during charge and cut the charger when Boost voltage is hit, no worries.

While the inverter has a 21V cut-off, since it's not adjustable, you can consider setting your BMS to cut off at a higher voltage.

 

[Johnyguy]

https://www.victronenergy.com/upload/documents/Datasheet-Multiplus-inverter-charger_2kVA-and-3kVA-120V-US-EN.pdf

20W

More efficient and can be easily programmed for a multitude of things.



Correct.



Correct.



Perfectly fine, and you CAN use it for AC charging, you just need to configure it for GEL or watch it and cut the charger when the battery hits ~14.2-14.4.



Some would say yes, but your cells can go to 20V (2.5V/cell). Furthermore, when connected to AC, the unit will not allow the batteries to discharge, but will keep them floated.



Absorption is flexible. 3.55-3.65V/cell will get you very nearly fully charged the moment you hit that voltage. If you are patient, cells can get to 98%+ SoC at 3.45V/cell.

Float at 3.4V/cell is generally recommended. Battleborn allows for up to 3.45V/cell, so there's some wiggle room.

Programs 2 and 4 would also work, but the long absorption time is undesirable. If you're willing to watch the voltage during charge and cut the charger when Boost voltage is hit, no worries.

While the inverter has a 21V cut-off, since it's not adjustable, you can consider setting your BMS to cut off at a higher voltage.

thank you for replying !!
So if i program my BMS to a higher cut off voltage how is that going to effect what the inverter try to do ( charging the battery) i am not sure about this part

 

[sunshine_eggo]

thank you for replying !!
So if i program my BMS to a higher cut off voltage how is that going to effect what the inverter try to do ( charging the battery) i am not sure about this part

If AC is connected to the input of the inverter, it will ALWAYS charge/float the battery and will not use the battery for power unless set to program 0.

On second thought, this inverter is going to have a high surge current when initially connecting to the battery (pre-charging the capacitors). Unless you have a VERY robust BMS, it will probably overload it.

Video on pre-charge.

 

[Johnyguy]

If AC is connected to the input of the inverter, it will ALWAYS charge/float the battery and will not use the battery for power unless set to program 0.

On second thought, this inverter is going to have a high surge current when initially connecting to the battery (pre-charging the capacitors). Unless you have a VERY robust BMS, it will probably overload it.

Video on pre-charge.

There is an option to have battery priority or AC priority like you said it's in the manuel ....

 

[Bvillebob]

Like the old saying goes, "cry once, buy once", menaing if you spend a ltitle more to get a better inverter/charger you'll be a lot happier in the long run. I spent a long time looking into the Sungoldpower inverters, at first they looked really attractive, but more and more negatives kept creeping in. For a few hundred dollars more I ended up buying the Samlex 4024 which I believe to be a far superior unit. Check out the prices on Samlex inverters at DonRowe.com, they beat everyone else by quite a bit (not affiliated in any way).

When you look at your overall investment in your system the difference in buying Tier 1 gear isn't that much and the performance improvements and peace of mind are valuable. If this is just an experimental project for you, that's one thing, if you're planning to power your home for a period of time, that's another, and the choices may differ.

 

[Johnyguy]

Like the old saying goes, "cry once, buy once", menaing if you spend a ltitle more to get a better inverter/charger you'll be a lot happier in the long run. I spent a long time looking into the Sungoldpower inverters, at first they looked really attractive, but more and more negatives kept creeping in. For a few hundred dollars more I ended up buying the Samlex 4024 which I believe to be a far superior unit. Check out the prices on Samlex inverters at DonRowe.com, they beat everyone else by quite a bit (not affiliated in any way).

When you look at your overall investment in your system the difference in buying Tier 1 gear isn't that much and the performance improvements and peace of mind are valuable. If this is just an experimental project for you, that's one thing, if you're planning to power your home for a period of time, that's another, and the choices may differ.

what is the stand by power consumbtion of your unit?

i am looking this unit PST-3000-24 24 VDC- 120 VAC
and i cannot find idle power draw!

 

[Johnyguy]

what is the stand by power consumbtion of your unit?

Like the old saying goes, "cry once, buy once", menaing if you spend a ltitle more to get a better inverter/charger you'll be a lot happier in the long run. I spent a long time looking into the Sungoldpower inverters, at first they looked really attractive, but more and more negatives kept creeping in. For a few hundred dollars more I ended up buying the Samlex 4024 which I believe to be a far superior unit. Check out the prices on Samlex inverters at DonRowe.com, they beat everyone else by quite a bit (not affiliated in any way).

When you look at your overall investment in your system the difference in buying Tier 1 gear isn't that much and the performance improvements and peace of mind are valuable. If this is just an experimental project for you, that's one thing, if you're planning to power your home for a period of time, that's another, and the choices may differ.

for a few hundred more???
Samlex EVO-4024 4000W Pure Sine Inverter/Charger
List Price: $2,185.60
Price: $1,748.50
Sale Price: $1,449.99

If i wanna spend this kind of money i would rather get the victron energy multyplus for $1300.00


The sungoldpower is : $655.00

 

[Johnyguy]

I am no expert but am looking into this as well. The term I have seen used most is “self consumption” where your inverter uses battery before grid.

There are quite a few, ranging from Growatt, to Victron Multiplus, Schneider Conext 4024 and more.


You should shoot for an even number of panels or you would need an inverter that accepts the 5x panel voltage as input (rare and very speedy). With 4 panels, 2S2P, 6 panels 3S2P or 2S3P are all reasonable array configurations.

Mr Sandals

the victron multyplus uses 20W idle power
The sungold uses 39W idle power
the victron is $1300 over the sungold $650 do you think idle power alone enough to buy the victron instead ?
I know the victron has bluetooth and more adjustment much better customer service , but alone the power saving would be enough ?
I know if i have a big battery which i dont only 8S i have so if i would have a big battery the power consumption is not a big deal.....
what is your thoughts?

also Maximum efficiency 94% victron versus 88% goldsun

 

[sunshine_eggo]

Mr Sandals

the victron multyplus uses 20W idle power
The sungold uses 39W idle power
the victron is $1300 over the sungold $650 do you think idle power alone enough to buy the victron instead ?

The Victron 90-94% efficient vs. the Sunpower 80-88%

I know the victron has bluetooth

It does not. It require a separate bluetooth dongle for VictronConnect or a MK3-USB for PC using VEConfigure3

and more adjustment much better customer service , but alone the power saving would be enough ?

Assuming 5% difference in efficiency, Multiplus would use 5% less energy + 0.48kWh less self-consumption per day. It may be a significant portion of your battery capacity.

 

[Johnyguy]

The Victron 90-94% efficient vs. the Sunpower 80-88%



It does not. It require a separate bluetooth dongle for VictronConnect or a MK3-USB for PC using VEConfigure3



Assuming 5% difference in efficiency, Multiplus would use 5% less energy + 0.48kWh less self-consumption per day. It may be a significant portion of your battery capacity.

you own the victron?

 

[sunshine_eggo]

you on the victron?

I have a Quattro 48/5K-120V (like the multiplus, but higher power and dual AC inputs) and all Victron hardware.

 

[MisterSandals]

what is your thoughts?

I am a big believer in buying quality SCCs more than any other piece of equipment. I love the Bluetooth for monitoring, configuring and super easy firmware updates.
About 11 years ago I spent way more than I wanted on my first nice SCC: Morningstar Tristar MPPT 45. I was convinced I lost my mind spending $750 on an 45A SCC. But, it was burried under the driver seat pedestal in my RV for about 9 years, on 24/7/365 without a hiccup. It did not support LiFePO4 batteries so it got pulled out during my battery upgrade. Turns out Morningstar firmware update makes setting up custom charge profile possible with a PC (ugg). So it’s now the greenhouse workhorse which is also the house “extension cord to refrigerator and freezer” backup power system.

Sorry for the novel but a good SCC should give many many years of service. I fortunately learned this the easy way.

I plan on spending $1500-$2500 when I figure out my grid tie, self consumption battery solution with 16x 280Ah cells. I expect (hope!) it to work for a decade+ and pay for itself.

I looked long and hard at the Multiplus and Quattro but they don’t quite do what my special case needs (incorporate micro inverters easily).

As was said earlier, buy once, cry once. Especially for SCCs.

 

[Johnyguy]

I am a big believer in buying quality SCCs more than any other piece of equipment. I love the Bluetooth for monitoring, configuring and super easy firmware updates.
About 11 years ago I spent way more than I wanted on my first nice SCC: Morningstar Tristar MPPT 45. I was convinced I lost my mind spending $750 on an 45A SCC. But, it was burried under the driver seat pedestal in my RV for about 9 years, on 24/7/365 without a hiccup. It did not support LiFePO4 batteries so it got pulled out during my battery upgrade. Turns out Morningstar firmware update makes setting up custom charge profile possible with a PC (ugg). So it’s now the greenhouse workhorse which is also the house “extension cord to refrigerator and freezer” backup power system.

Sorry for the novel but a good SCC should give many many years of service. I fortunately learned this the easy way.

I plan on spending $1500-$2500 when I figure out my grid tie, self consumption battery solution with 16x 280Ah cells. I expect (hope!) it to work for a decade+ and pay for itself.

I looked long and hard at the Multiplus and Quattro but they don’t quite do what my special case needs (incorporate micro inverters easily).

As was said earlier, but once, cry once. Especially for SCCs.

thanks for your input !

for the charge controller i will go with a victron of course but for the inverter i cannot spend $1300 it is too much for me right now this is more like a experiment than a need .
I agree the victron is a well known brand and efficent all that but it is juts too much for me .....
I am still thinking to hardwire the inverter with the fridge and also some lights livingroom ,bedroom.
Otherwise the battery i ordered is just going to sit here without use for a emergency .( i hope there is non)

I have room for 3 plus 3 panels on the balcony i think maybe just 4 total so that would be 210Wx4=840W or 6x210W= 1260W
I thought i would put them in paralel because not all of them would be in direct sun ..

you said :
If you got 3 or 4 big panels,
900-1000W, you might be ok.

To just recharge, with nothing running, not even the fridge, you would need:
7168Wh / 5h = 1433W of panels to recharge in a day under perfect conditions an 100% efficiency. If you matched array to battery, for single day recharge, with loads, you’d be over 2000W of solar.

I read in a other post that the guy uses a full size fridge with same size battery but most likely he has more panels to recharge them ...hmmm

so if i am planing to use 840W for charging than it is a pipe dream i guess
wont be able to use it for the fridge only for lights ,computer...
Than i can use a smaller inverter...

right now i am paying $1-$2 per day for electricity with my usage soo inexspensive what is the point of all this solar to be hoenst !

for me at least

what should i do with the batterys ? just build a portable system for emergency?

 

[MisterSandals]

what should i do with the batterys ? just build a portable system for emergency?

I went and reread your OP. Buying and then asking questions has been an unfortunate scenario we have seen too often.
It looks like you’ve learned quite a bit and see that solar is not often a profitable venture; it’s usually out of a necessity for power that makes solar worthwhile.

You’ve ordered a good product in the 8x cells. They will hold a reasonable amount of power that could keep your fridge and laptop going for a day or two in an emergency. My emergency inverter is a 1200W Giandel sine wave that cost around $200 a few years ago. Not good enough for full time service but good enough to keep fridge and freezer going in an emergency via extension cord.

And when your cells arrive, you’ll have a fun project and learning experience.

<\end of rambling>

 

[Johnyguy]

I went and reread your OP. Buying and then asking questions has been an unfortunate scenario we have seen too often.
It looks like you’ve learned quite a bit and see that solar is not often a profitable venture; it’s usually out of a necessity for power that makes solar worthwhile.

You’ve ordered a good product in the 8x cells. They will hold a reasonable amount of power that could keep your fridge and laptop going for a day or two in an emergency. My emergency inverter is a 1200W Giandel sine wave that cost around $200 a few years ago. Not good enough for full time service but good enough to keep fridge and freezer going in an emergency via extension cord.

And when your cells arrive, you’ll have a fun project and learning experience.

<\end of rambling>

Thank you I will

 

[Johnyguy]

I have a Quattro 48/5K-120V (like the multiplus, but higher power and dual AC inputs) and all Victron hardware.

Hi let me ask you a question is your victron Quattro can be wired so when the battery power gets too low it is switches over to AC grid than when the battery is recharged by solar and its full than goes back to battery ?

Thanks

 

[sunshine_eggo]

Hi let me ask you a question is your victron Quattro can be wired so when the battery power gets too low it is switches over to AC grid than when the battery is recharged by solar and its full than goes back to battery ?

Thanks

Not wired, but it can be programmed to behave that way. Victron has downloadable "assistants" that allow for all kinds of custom behavior. I have not yet had to use one, but I just went though it, and using some rules, I was able to generate criteria to "ignore" AC input when battery voltage is above a specified voltage for at least X time. It doesn't completely capture your criteria, but other criteria can be layered on top of that such as state of charge.