LV5048 Solar Charging Confusion

Darren Orange

Solar Enthusiast
Joined
Feb 25, 2021
Messages
45
Hi,

I have a LV5048 and it has been working great for almost a year now, however I only recently got solar panels. The panels are running typically run around 80V I have a 2S5P setup for this for a total of 4kw or 400w a panel. This is on solar input #2, nothing is on solar input #1.

Let me start with this my batteries are not fully charged around 53V out of 57V battery size is about 13.5kWh. It has started charging the batteries as is normal and running our house as well off the solar panels.

So I've noticed something strange with the solar today such that it is pulling more power up to a point from the solar array when the load goes up. I was able to test this with a microwave. I figure I might have a setting wrong or something.

I know that it is showing my load is almost matched to my PV power at the moment I added my car as a load to pull more power to max out the power from the array but if I disconnect the car the power output from the array will drop ~300 watts and its about noon. Maybe I'm wrong but something seems a bit weird?

Thanks in advance for any help.

LV5048Capture.JPGLV5048Capture2.JPG
 

snoobler

Solar Honey Badger
Joined
Jul 10, 2020
Messages
8,430
Location
HBR, AZ
Welcome to the forum.

Based on the information provided, you have your bulk and float voltage at 57.0V. This is very bad unless it's consistent with your battery manufacturer's recommendation. If you've run this way for 1.5 years, and it's not to battery spec, I would expect your batteries are damaged.

The 53.7V it happens to be running at is a much more common "float" voltage. You describe it as behaving like it's trying to maintain this float voltage.

The only way to test the full power of your array is to apply loads that exceed the array's output

When a battery is in absorption or float mode, it's VOLTAGE limited, i.e., it will only pull as many amps as needed to maintain that voltage.

Even though the SoC indicates less than 100%, it's behaving as thought it's trying to maintain a float voltage, and only pulling enough power needed to supply the loads.

Your 4kW array will likely never pull 4kW unless you're on the equator, at sea level, on an equinox, with your panel facing straight up, high noon and with perfectly clear skies. Most other situations will result in less power by at least 10-20%. When the sun is in the other hemisphere, power can be notably reduced.

Since you're new to solar input, double check your settings. IIRC, you can set multiple current limits - solar, grid, total, etc.
 

DeniseN

Solar Enthusiast
Joined
Aug 27, 2020
Messages
73
Hi. I recall reading that if you are only using one of the two pv inputs, use input one.
 

apctjb

Solar Addict
Joined
Jun 16, 2020
Messages
273
The 53.7V it happens to be running at is a much more common "float" voltage. You describe it as behaving like it's trying to maintain this float voltage.

Agree; seems like you are in float mode. Is the charging light on? Is it steady or flashing?
 

Darren Orange

Solar Enthusiast
Joined
Feb 25, 2021
Messages
45
Agree; seems like you are in float mode. Is the charging light on? Is it steady or flashing?
My float is set to 57V. It should not be causing anything. My batteries can charge full flank speed up to 57V and absorb up there. 57V is not fully charged for my batteries so it should be a non issue. I'm going to have to keep playing with settings to figure out what is causing it to step down the charging some prematurely.
 

snoobler

Solar Honey Badger
Joined
Jul 10, 2020
Messages
8,430
Location
HBR, AZ
My float is set to 57V. It should not be causing anything. My batteries can charge full flank speed up to 57V and absorb up there. 57V is not fully charged for my batteries so it should be a non issue. I'm going to have to keep playing with settings to figure out what is causing it to step down the charging some prematurely.

Are you using Li-ion chemistry (3.6-3.7V nominal)?
 

apctjb

Solar Addict
Joined
Jun 16, 2020
Messages
273
What battery type did you select under the battery setting? (setting 5 on Growatts)
 

Darren Orange

Solar Enthusiast
Joined
Feb 25, 2021
Messages
45
I HAVE SOLVED MY PROBLEM!

I failed to read the instructions...so I think it solved it.

I failed to follow the instructions correctly. I plugged the solar into MPPT2 rather than 1. I only have one array it must be in 1 or it acts weird. Not sure if this matches up with others issues...but it says to do this in the instructions. I feel foolish...at least nothing exploded.
 

Darren Orange

Solar Enthusiast
Joined
Feb 25, 2021
Messages
45
Problem 2 solved!!!!!

In the controls for solar charging where you set the max amps allowed to charge the battery that value is divided by 2. All LV5048 units have two MPPT inputs and regardless if you are only using one it still splits this max charging amps value.

If you set it to 40 amps, it will only ever allow 20 amps of max charging from MPPT1. If you are only using MPPT1 and you want to pull max amps from the array you need to set it to 160 amps, which will allow MPPT1 to charge at a max of 80 amps or it's rated max value.

Obviously you want to limit this based upon your batteries, for example my batteries I only ever want to allow 50 amps so I need to set this to 100amps.

Also from my experience I can only use the watch power or icc solar software to set it to 60amps you must do the change on the unit itself to set it higher than 60 amps.

This information is certainly not in the manual and needs to made more clear to the users.

This is not really an issue I don't think for other units but it is here. If the unit can pull more power from the solar but it is just limited charging power it will pull more power from the panels first. It will surge to the batteries when the load drops but then it will cut back to max charging rating.
 
Top