2Kw Inverter shuts down after 2 mins plugged in (1 lithium battery)

[free2b]

Hi electrical pros...

I have 2, 160w roof panels, a 2K w Xantrex mppt solar charger, 1-Battleborn 100 amp hr lithium battery. While plugged into 30 amp, the Xantrex runs for 1.5-2 mins using a 700W microwave, then shuts off. Restarting the microwave repeats the same behavior until the Xantrex and Victron shuts down. Then, no power for 20 mins and everything comes back up.  

From what I'm seeing on my Victron app, it looks like my battery is being depleted, so I'm guessing a need another battery.  What I don't understand is, since I'm plugged in and I can see the system is charging, why does the inverter shut off after 2 mins 2-3x and then my 100 amp hour battery is depleted?  Did I miss a setting on the inverter?

I'm hoping to go full time in about 2 weeks.  

Thanks for any help.

 

[barleyguy]

You're triggering the low voltage cut off on the inverter, because the draw of the microwave is pulling too much power for the 100 ah battery, which causes the battery voltage to go too low during that high draw. You either need a second battery as you suspected, or a smaller lower wattage microwave.

There might be a setting on the inverter for changing the low voltage cutoff. But lithium batteries don't ramp down gradually like lead acid, so it may not help. You can repeat your test while putting a voltmeter on the inverter input, and you should see the voltage drop when it shuts down.

 

[jonyjoe303]

Your battleborn is probably not fully charged. I have seen a 100ah lithium battery, supply over 1500 watts for over 20 minutes before it shutdown, so the lithium can easily handle 700 watts for more then 2 minutes. On lifepo4 the voltage only drops low enough to shutoff the inverter when its not fully charged.

Do you have a coulombmeter to measure the amps going into your battery during charging? thats the only way to really measure what the battery charge is. If your charging your lithium with solar, you might never get a full charge on your battery especially if there is voltage drop. Without a coulombmeter it's impossible to know the status of a lifepo4 battery. Voltage would only be accurate if you can see the individual cell voltage(4 cells) of your lifepo4 (not possible with drop-in lithium) if all 4 cells each reach 3.65 volts, then the battery is fully charge. If your battery reaches 14.6 volts and holds it there for a while and there is no voltage drop then your close to a full charge.

With battleborn they recommend a bulk/absorbtion charge of 14.4 volts, which means the battery has to sit at 14.4 volts for hours, lifepo4 in reality doesnt fully charge until 14.6 volts. And if you got voltage drop you might not even be reaching 14.4 volts. Check the voltage at the terminals while charging to find out the true max voltage your charger is putting out.

There is a video on youtube called "lithium battery test versus gel" that shows what kind of performance you can expect from your 100ah lifepo4 on very high loads, you should get at least 20 minutes with a fully charge battery.

 

[free2b]

You're triggering the low voltage cut off on the inverter, because the draw of the microwave is pulling too much power for the 100 ah battery, which causes the battery voltage to go too low during that high draw.  You either need a second battery as you suspected, or a smaller lower wattage microwave.

There might be a setting on the inverter for changing the low voltage cutoff. But lithium batteries don't ramp down gradually like lead acid, so it may not help. You can repeat your test while putting a voltmeter on the inverter input, and you should see the voltage drop when it shuts down.

Thanks for helping me out   I did read that, in order to fully utilize the 2000w xantrex, I should have 2 lithium batteries.  My Victron energy monitor shows my battery discharged 118 ah over 4 minutes of using my 700w microwave.  What I don't get is, why doesn't it use shore power instead of the battery?

 

[free2b]

Your battleborn is probably not fully charged. I have seen a 100ah lithium battery, supply over 1500 watts for over 20 minutes before it shutdown, so the lithium can easily handle 700 watts for more then 2 minutes. On lifepo4 the voltage only drops low enough to shutoff the inverter when its not fully charged.

Do you have a coulombmeter to measure the amps going into your battery during charging? thats the only way to really measure what the battery charge is. If your charging your lithium with solar, you might never get a full charge on your battery especially if there is voltage drop. Without a coulombmeter it's impossible to know the status of a lifepo4 battery. Voltage would only be accurate if you can see the individual cell voltage(4 cells) of your lifepo4 (not possible with drop-in lithium) if all 4 cells each reach 3.65 volts, then the battery is fully charge. If your battery reaches 14.6 volts and holds it there for a while and there is no voltage drop then your close to a full charge.

With battleborn they recommend a bulk/absorbtion charge of 14.4 volts, which means the battery has to sit at 14.4 volts for hours, lifepo4 in reality doesnt fully charge until 14.6 volts. And if you got voltage drop you might not even be reaching 14.4 volts. Check the voltage at the terminals while charging to find out the true max voltage your charger is putting out.

There is a video on youtube called "lithium battery test versus gel" that shows what kind of performance you can expect from your 100ah lifepo4 on very high loads, you should get at least 20 minutes with a fully charge battery.

Thanks.  I'll check out the video.  

My victron app shows my Battleborn is charged 100%. I'm plugged into shore power. The Victron app shows 13.8 volts with 2 12v fans and a dometic fridge running.   I don't have a [font=Tahoma, Verdana, Arial, sans-serif]coulombmeter. Don't know what that is!  

I should probably go through the Xantrex settings to make sure it's set for a lithium battery and at 14.4 volts. I've never seen volts higher than 14.2 when plugged into shore power.  Could a setting in the Xantrex be limiting the volts?

As I already posted, I don't understand why shore power doesn't take over the draw. I understood that, the Xantrex automatically switched to shore power when plugged in. That's not happening.

Thanks for helping me out.
[/font] I posted a pic but it didn't post I guess because I'm new.

 

[highdesertranger]

well if the Xantrex is suppose to auto switch and it's not something is wrong. got a link to the model you have? it would really help.

couple of things off the top of my head,

is there a breaker on the feed? there should be, reset it even if it looks like it hasn't tripped.
check the feed for power
check the fuse between the inverter and the battery.
if you don't mind me asking are you absolutely sure everything is is connected correctly? did it ever work correctly?

that's just a couple of things off the top of my head.

highdesertranger

 

[theBest]

Your battleborn is probably not fully charged. I have seen a 100ah lithium battery, supply over 1500 watts for over 20 minutes before it shutdown, so the lithium can easily handle 700 watts for more then 2 minutes. On lifepo4 the voltage only drops low enough to shutoff the inverter when its not fully charged.

Do you have a coulombmeter to measure the amps going into your battery during charging? thats the only way to really measure what the battery charge is. If your charging your lithium with solar, you might never get a full charge on your battery especially if there is voltage drop. Without a coulombmeter it's impossible to know the status of a lifepo4 battery. Voltage would only be accurate if you can see the individual cell voltage(4 cells) of your lifepo4 (not possible with drop-in lithium) if all 4 cells each reach 3.65 volts, then the battery is fully charge. If your battery reaches 14.6 volts and holds it there for a while and there is no voltage drop then your close to a full charge.

With battleborn they recommend a bulk/absorbtion charge of 14.4 volts, which means the battery has to sit at 14.4 volts for hours, lifepo4 in reality doesnt fully charge until 14.6 volts. And if you got voltage drop you might not even be reaching 14.4 volts. Check the voltage at the terminals while charging to find out the true max voltage your charger is putting out.

There is a video on youtube called "lithium battery test versus gel" that shows what kind of performance you can expect from your 100ah lifepo4 on very high loads, you should get at least 20 minutes with a fully charge battery.

Focus on testing. Simple basic meter testing can show where you need to focus.
In order to determine amperes you need a clamp meter that can encircle the wires to determine what is traveling through the wire into the battery.
Batteries have a happy range, n volts and x amps. Use the specifications to determine your batteries needs.
What is the depth of discharge rating, 50%, 80%, 100%?
How many charge/discharge cycles can the battery handle before you need to buy another?
There is a reason why many people use lead acid batteries for solar.
AGM batteries are better than Li batteries, not as expensive as solar specific batteries, and the AGM’s are much better than auto or golf cart batteries. This is because of the type of lead in various batteries, lead foam versus thin plates versus thick plates.
The higher the depth of discharge the better. A 120 amp hour rated battery with a 50% depth of discharge means you only have 60 amp hours available for use.

 

[free2b]

well if the Xantrex is suppose to auto switch and it's not something is wrong.  got a link to the model you have? it would really help.

couple of things off the top of my head,

is there a breaker on the feed?  there should be,  reset it even if it looks like it hasn't tripped.
check the feed for power
check the fuse between the inverter and the battery.
if you don't mind me asking are you absolutely sure everything is is connected correctly?  did it ever work correctly?

that's just a couple of things off the top of my head.

highdesertranger

Thanks for your help.  I don't think I can post a link because I'm new, but I'll try... 

www.xantrexDOTcom/power-products/inverter-chargers/freedom-xc.aspx

This is the first time I've tried the inverter since I had the system installed.  I don't know if it's installed correctly, but the solar works well.  I checked the fuses and they all appear to be fine.  I reset the inverter, but the same problem. The 700w microwave is demolishing my battery in 6 mins.  I'm going to check the setup to make sure it's set for lithium and not agm, gel etc.  The only video I found about set up is fuzzy pretty poorly done, or at least I can't follow it.  Will dig out the user manual.  Pretty weird that.it won't switch to shore power.  I'm thinking it might be a setting.

When the invertererter quits, why does my whole system die for 20 mins?  

So confused...  Thanks for helping.

 

[highdesertranger]

the link doesn't work. I can't find an inverter/solar controller combo on their website. they do have inverter/battery charger combos. so I am confused with what we are dealing with. highdesertranger

 

[jonyjoe303]

The victron monitor you have might be a coulombmeter if it has a shunt that tracks amps in/out of the battery. But if it reports your battery at 100 percent it might not be properly calibrated. You said that the most voltage you see is 14.2 volts, that means the battery is not reaching full charge, and with lifepo4 if you never fully charge it, it might still read 100 percent but be at 20 or 30 percent. When your at 30 percent a heavy load will easily cause the voltage to sag enough to trip the inverter and also might cause the battery bms to shutdown, that is why it is taking a while for the power to come back on (bms reset).

When you mention that the victron monitor shows you used 118ah over 4 minutes that shows the victron is miscalibrated. 700 watts divided by 13 volts = 53 amps, that means your microwave is using 53 amps and technically your battery can run it for over 1 hour , when fully charged. The battleborn can discharge at 100 amps constantly so 53 amps is insignificant for it when fully charged.

I have a 220ah lifepo4 and know firsthand how hard it is to fully charge to 100 percent with solar. A good coulombmeter will automatically reset to 100 percent when the battery reaches the max voltage you program as full charge.
If possible I would try to fully charge to 14.6 volts at least once, to know you have a full battery. Then you can charge to 14.4 volts. The battery is suppose to last longer at lower voltages but it also makes it harder to fully charge. Check the voltage at the terminals, that will give you the most accurate reading.

Here is a picture of my lifepo4 reaching 14.6 volts with solar, every once in a while you need to get the battery very close to 14.6 volts.

 

[free2b]

the link doesn't work.  I can't find an inverter/solar controller combo on their website.  they do have inverter/battery charger combos.  so I am confused with what we are dealing with.  highdesertranger

Sorry...

http://www.xantrex.com/power-products/inverter-chargers/freedom-xc.aspx

 

[highdesertranger]

the instructions are 90 pages it will take some time to read. have you read the instruction sheet and do you understand it? there are several setting that you must set.

but first what is your low voltage cutoff set at?

highdesertranger

 

[theBest]

the link doesn't work.  I can't find an inverter/solar controller combo on their website.  they do have inverter/battery charger combos.  so I am confused with what we are dealing with.  highdesertranger

http://www.xantrex.com/power-products/inverter-chargers/freedom-xc.aspx

Edit: My spell checker does not like aspx, argh.
I see he has removed the “DOT”and replaced it with “.”.
Carry on then.