Probably dumbest question ever

[Jamasarah]

Today I was told that I would not be able to use the full potential power of my LV 6048, if I didn’t have enough batteries to equal it?‍So Would that mean that if all I ever used was around 2000 W, I could never use it unless I had the battery storage equaling 2000w?

 

[RickP]

If I’m understanding your question right, yes, you have to have enough energy stored (or being made at that moment, or shore power) in order to power a 2000 watt load. The inverter needs something to invert or pass through in order to provide power.

 

[chrisski]

I think that’s a bit off. You do need a lot of batteries to run a 2000 watt inverter for any amount of time.

Batteries don’t store watts, they store watt hours. A 2000 watt inverter run for 6 minutes uses 200 watt hours. So, part of the eqation would be you’d need at least 200 watt hours stored in your batteries.

Add to that, you don’t want to discharge your batteries below a certain percentage, so let’s say that’s a lead acid battery, which is 50%.

Another part is the battery has to handle the amps being put out by the inverter, which probably won’t be a factor with a couple of batteries.

A 6 volt golf cart battery holds around 200 amp hours of energy, or 1200 watt hours of energy, 600 watt hours usable. So that battery will run that inverter for 18 minutes.

Of course you won’t have a single 6 volt battery, you’ll have two in series for 12 volts, and now you have about 2400 watt hours of energy, or 1200 watt hours usable, and now you can run that inverter at 2000 watts for 36 minutes before your battery gets to 50%.

If you’re using lead acid and pulling that much energy, there’s a Puekert effect, which is like going heavy on the gaS where you burn more gas to go just as far. So the battery will get to 50% a bit earlier than 36 minutes.

But if you want to add solar panels in the daytime, you can use this free energy, but you can’t put too many panels on or they will push too much power to the battery.

For my lead acid batteries, that is about 13% of the pack or about 25 amp for the two batteries I mentioned. 25 amp hours is maybe 300 watts, which still means your inverter is pulling from the batteries 1700 watts.

With lithium you can charge the batteries at 50% so about 100 amps or 1200 watts, so even though the panels are pushing a lot more energy, you’re still short 800 watts that come from the batteries.

 

[kromc5]

The manual gives you some information about loads and recommend batteries but would calculate the loads.

 

[Jamasarah]

I think that’s a bit off. You do need a lot of batteries to run a 2000 watt inverter for any amount of time.

Batteries don’t store watts, they store watt hours. A 2000 watt inverter run for 6 minutes uses 200 watt hours. So, part of the eqation would be you’d need at least 200 watt hours stored in your batteries.

Add to that, you don’t want to discharge your batteries below a certain percentage, so let’s say that’s a lead acid battery, which is 50%.

Another part is the battery has to handle the amps being put out by the inverter, which probably won’t be a factor with a couple of batteries.

A 6 volt golf cart battery holds around 200 amp hours of energy, or 1200 watt hours of energy, 600 watt hours usable. So that battery will run that inverter for 18 minutes.

Of course you won’t have a single 6 volt battery, you’ll have two in series for 12 volts, and now you have about 2400 watt hours of energy, or 1200 watt hours usable, and now you can run that inverter at 2000 watts for 36 minutes before your battery gets to 50%.

If you’re using lead acid and pulling that much energy, there’s a Puekert effect, which is like going heavy on the gaS where you burn more gas to go just as far. So the battery will get to 50% a bit earlier than 36 minutes.

But if you want to add solar panels in the daytime, you can use this free energy, but you can’t put too many panels on or they will push too much power to the battery.

For my lead acid batteries, that is about 13% of the pack or about 25 amp for the two batteries I mentioned. 25 amp hours is maybe 300 watts, which still means your inverter is pulling from the batteries 1700 watts.

With lithium you can charge the batteries at 50% so about 100 amps or 1200 watts, so even though the panels are pushing a lot more energy, you’re still short 800 watts that come from the batteries.

I think that’s a bit off. You do need a lot of batteries to run a 2000 watt inverter for any amount of time.

Batteries don’t store watts, they store watt hours. A 2000 watt inverter run for 6 minutes uses 200 watt hours. So, part of the eqation would be you’d need at least 200 watt hours stored in your batteries.

Add to that, you don’t want to discharge your batteries below a certain percentage, so let’s say that’s a lead acid battery, which is 50%.

Another part is the battery has to handle the amps being put out by the inverter, which probably won’t be a factor with a couple of batteries.

A 6 volt golf cart battery holds around 200 amp hours of energy, or 1200 watt hours of energy, 600 watt hours usable. So that battery will run that inverter for 18 minutes.

Of course you won’t have a single 6 volt battery, you’ll have two in series for 12 volts, and now you have about 2400 watt hours of energy, or 1200 watt hours usable, and now you can run that inverter at 2000 watts for 36 minutes before your battery gets to 50%.

If you’re using lead acid and pulling that much energy, there’s a Puekert effect, which is like going heavy on the gaS where you burn more gas to go just as far. So the battery will get to 50% a bit earlier than 36 minutes.

But if you want to add solar panels in the daytime, you can use this free energy, but you can’t put too many panels on or they will push too much power to the battery.

For my lead acid batteries, that is about 13% of the pack or about 25 amp for the two batteries I mentioned. 25 amp hours is maybe 300 watts, which still means your inverter is pulling from the batteries 1700 watts.

With lithium you can charge the batteries at 50% so about 100 amps or 1200 watts, so even though the panels are pushing a lot more energy, you’re still short 800 watts that come from the batteries.

Hummm, we’ll this is a fine mess I’ve gotten myself into?
I bought the LV 6048, Figuring I would grow into it someday. I only bought four lead acid 12 V Delco deep cycle marine Batteries, Just to get by with for now.
At this time I am only using about 300 W a day but I do have the 16, 250w panels.
So do u think, because I have only four 12 V batteries in parallel that when I try to pull more power from my unit it shuts down, even though I have plenty of power coming through the panels ?‍? Maybe too much for the batteries?

 

[Hedges]

Determine proper charge current for your battery bank and program LV 6048 to charge at that rate. Excessive current would damage them.

"Marine Deep Cycle" won't work well as solar batteries, but should be fine to deliver a starting surge for motors.
Lots of PV panels (4kW) is good. Set them up with morning and afternoon sun orientations, so power production is fairly flat during the day.

Don't discharge the batteries powering loads. Only apply loads that let batteries be kept at float voltage. Make whatever while the sun shines.

Automating that would be an electrical engineering exercise, but if you observe battery is at float voltage and PV array is higher than Vmp, then there is surplus power available.

I believe in using the smallest battery possible.

 

[chrisski]

I don’t know the all in one inverter to well. For these Delhi batteries, what is there ratings in amp hours?

Also are the batteries FLA or AGM?

 

[Jamasarah]

If I’m understanding your question right, yes, you have to have enough energy stored (or being made at that moment, or shore power) in order to power a 2000 watt load. The inverter needs something to invert or pass through in order to provide power.

Ok, now I’m really lost?
Example: I have a solar pump that pulls up water from 400’ with no batteries attached!
Works like a charm, I fill my holding tank during the day, once every 3 days for yrs now?‍
So why can’t I run my MPP LV6048 all day, while the sun is out? I thought the batteries were just backup? I really don’t care if I have electricity at night??

 

[Bud Martin]

Will's video Batteryless SCC: www.youtube.com/watch?v=4kvSXx7sntk

 

[MichaelK]

Hummm, we’ll this is a fine mess I’ve gotten myself into?
I bought the LV 6048, Figuring I would grow into it someday. I only bought four lead acid 12 V Delco deep cycle marine Batteries, Just to get by with for now.
At this time I am only using about 300 W a day but I do have the 16, 250w panels.
So do u think, because I have only four 12 V batteries in parallel that when I try to pull more power from my unit it shuts down, even though I have plenty of power coming through the panels ?‍? Maybe too much for the batteries?

Let's assume that those batteries are 120Ah. Most flooded lead-acid batteries like a charging rate of about 1/8 of C, or in your case 120Ah X 0.125C= 15Amps. With a 48V system charging at 50V during bulk, you need 15Amps X 50V X 1.175fudgefactor = 881W of panels, more or less.

With 16 250W panels, you can make 4000W, so that is grossly excessive for your battery size. Your battery really should be (4000W/50V) X 0.85fudgefactor X 8fold capacity = 544Ah of battery. So, you need 4-5 times the battery capacity for that amount of power.

One important consideration with small batteries is "ripple current", the fluctuations in the DC voltage caused by AC. It can be damaging to your solar electronics if large enough. Read though the attached file for more info on ripple current.

Those batteries are not the best choice, and assume they are not going to last long. I'd start shopping now for potential replacements. This is my battery, which is in the right size range for what you need.

8 CS 17P | Rolls Battery

www.rollsbattery.com

 

[Hedges]

With 16 250W panels, you can make 4000W, so that is grossly excessive for your battery size. Your battery really should be (4000W/50V) X 0.85fudgefactor X 8fold capacity = 544Ah of battery. So, you need 4-5 times the battery capacity for that amount of power.

But, if LV 6048 can be programmed for 15A (or whatever is optimum for this battery), the 4kW array is great because inverter can power all sorts of household loads while maintaining steady 15A charge rate. If battery size was such that it required 100% of PV to hit target charge rate, it would normally be charged too slowly.

That's what I've done with 12kW of PV and 20 kWh of AGM. My charge rate is set to 85A.

 

[Surferdudemi]

Hummm, we’ll this is a fine mess I’ve gotten myself into?
I bought the LV 6048, Figuring I would grow into it someday. I only bought four lead acid 12 V Delco deep cycle marine Batteries, Just to get by with for now.
At this time I am only using about 300 W a day but I do have the 16, 250w panels.
So do u think, because I have only four 12 V batteries in parallel that when I try to pull more power from my unit it shuts down, even though I have plenty of power coming through the panels ?‍? Maybe too much for the batteries?

If I've got the right device (looking up LV6048 on Google) those batteries have to be in series, because that's a 48v inverter.

 

[MichaelK]

But, if LV 6048 can be programmed for 15A (or whatever is optimum for this battery), the 4kW array is great because inverter can power all sorts of household loads while maintaining steady 15A charge rate. If battery size was such that it required 100% of PV to hit target charge rate, it would normally be charged too slowly.

That's what I've done with 12kW of PV and 20 kWh of AGM. My charge rate is set to 85A.

That's how I programmed my Midnight controllers, to limit amps. But, can the MPP be programmed that way? Anyone have the manual on that?

 

[Bud Martin]

I can set charging current on my MPP Solar.
See page 14 and page 16

http://www.mppsolar.com/manual/SPLIT%20PHASE%20LV/LV6048%20split%20phase%20manual-20201120.pdf

 

[Jamasarah]

If I've got the right device (looking up LV6048 on Google) those batteries have to be in series, because that's a 48v inverter.

I was told that you had to put them in parallel to make them work for 48 V ?‍

That's how I programmed my Midnight controllers, to limit amps. But, can the MPP be programmed that way? Anyone have the manual on that?

There is also an updated manual for the MPPLV6048 the addition is 1.2

 

[Hedges]

I was told that you had to put them in parallel to make them work for 48 V ?‍

??
Four 12V batteries in parallel is 12V, more current available.
In series, 48V.

Measure voltage at inverter terminals. Check manual of inverter. If you measure 12V to 14V, and manual says 48V or maybe 42V to 60V, that's your problem.

Photo of your batteries and cables?

 

[Jamasarah]

I don’t know the all in one inverter to well. For these Delhi batteries, what is there ratings in amp hours?

Also are the batteries FLA or AGM?

I’m not sure, I will ask, and (Delhi) that was auto correct they r Delco

 

[Bud Martin]

I am curious as to who chooses this system and set it up for you.

 

[Jamasarah]

??
Four 12V batteries in parallel is 12V, more current available.
In series, 48V.

Measure voltage at inverter terminals. Check manual of inverter. If you measure 12V to 14V, and manual says 48V or maybe 42V to 60V, that's your problem.

Photo of your batteries and cables?

Oopsie I got it mixed up, they r in series, checked it myself

 

[Jamasarah]

??
Four 12V batteries in parallel is 12V, more current available.
In series, 48V.

Measure voltage at inverter terminals. Check manual of inverter. If you measure 12V to 14V, and manual says 48V or maybe 42V to 60V, that's your problem.

Photo of your batteries and cables?

Oopsie they are in series, my memory has failed once again ?