What is normal behavior for an inverter charger?

gcp

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I have the Renogy 2000Watt Inverter Charger and it's my first time using an inverter charger. I'm confused by its behavior, but maybe this is normal:

When I plug into shore power, my batteries are charged to 100% by the inverter charger, but then after reaching 100% charge, the inverter charger only provides power to the AC circuit. My 12v circuit immediately begins draining the fully charged batteries. I've seen the batteries drain below 60%, and by then, the sun has come back up and my solar array starts charger the batteries and providing power to the 12v circuit. The inverter charger never does anything else except power the AC circuit.

Is it normal for an inverter charger to do this? Thanks!

Power System Wiring Diagram v4.7.001.jpeg
 

smoothJoey

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Depends on the configuration of the charge profile.
Sounds like you don't have float configured.
 

gcp

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Depends on the configuration of the charge profile.
Sounds like you don't have float configured.
I have it set to use the default LiFePo charging profile, which prevents customization of certain settings like Float profile/voltage. I'll try manually configuring it and see what happens.
 

smoothJoey

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I have it set to use the default LiFePo charging profile, which prevents customization of certain settings like Float profile/voltage. I'll try manually configuring it and see what happens.
Please post details of the default LFP charge profile.
 

gcp

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Please post details of the default LFP charge profile.
The manual provides few details. This is all it says: LiFePo profile will stop charging at 14.7v. Charging will resume at 12.5v.
 

gcp

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I noticed that if I briefly switch the battery disconnect to “off” and then back to “on” the inverter charger kicks in and charged my batteries back to 100%. But after that, the same thing happens all over again. It lets my 12v circuit discharge the batteries.
 

smoothJoey

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I’ve noticed that if I turn off the battery dis

thats the one!
It provides the info we need.
starting on page 20
Suggest a charge voltage of 3.55 volts per cell
If you want float set it no higher than 3.35 volts per cell
If not, make sure you have "Battery low voltage open charging" at the voltage where you want to re-enter bulk/absorb
 

time2roll

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The manual provides few details. This is all it says: LiFePo profile will stop charging at 14.7v. Charging will resume at 12.5v.
Not unreasonable to cycle the battery to 12.5 volts before charging starts again. Although many would have that set to 13.0 - 13.2 range. 12.5 is fine when using utility power because no real reserve is needed. If using a generator, the inverter should start charging as soon as you plug in regardless of standing voltage. And of course if the solar provides plenty of power there is no reason for the inverter to top up the battery.

Holding an LFP battery at full charge is a hangover from the lead-acid days. LFP is better to cycle and no issues to hang around at less than full charge.
 

Sojourner1

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I would set it up with a customized setting not the preset li setting.

You don't say the size of your battery bank so it's hard to compare what 40% dod overnight at 12v while still plugged in have 120v passing through ac power and not inverting.

I don't have Renogy (using Magnum hybrid) but this is my experience or what I do with my system when connecting to shore power which isn't often as I fulltime boondock. System in signature. Bulk/ absorb 14.1v (absorb set for 10 minutes, last 6 minutes. Can't be turned off) "float" 13.6v. I use my system everyday. Magnum has the ability to individually shut off the charging, inverting. I'll set my incoming loadshare to what the power is plugged into 15a, 30a, 50a. I'll turn off the charging from the inverter/ charge while letting the solar top off the batteries the next day but the inverter is left on "sleeping" so if there is a power loss it just wakes up and takes over till ac power is restored.

Now all 12v items are being powered by the batteries and all other appliances are being power by 120v power. When the furnace runs alot during the night and other misc 12v items are being powered, the average depleted from the batteries is 30-60ah by the time sun recharges the small amount and keeps them topped off till nighttime or a power outage.
 
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PerryB67

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You don't say the size of your battery bank so it's hard to compare what 40% dod overnight at 12v while still plugged in have 120v passing through ac power and not inverting.
According to his schematic in post #1 he has 340 ah's of batteries.

Enjoy,

Perry
 
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PerryB67

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I've seen the batteries drain below 60%, and by then, the sun has come back up and my solar array starts charger the batteries and providing power to the 12v circuit. The inverter charger never does anything else except power the AC circuit.

Is it normal for an inverter charger to do this? Thanks!
Perhaps I'm reading this wrong (I'm dyslexic), using 40% of your 340 ah's at night seems quite high for the camper in your schematic. What loads are you running at night?

Enjoy,

Perry
 
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gcp

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I agree at 340ah 40% is high especially if your plugged in.
Perhaps I'm reading this wrong (I'm dyslexic), using 40% of your 340 ah's at night seems quite high for the camper in your schematic. What loads are you running at night?

Enjoy,

Perry
That's cumulative drain, not just in one night. I'm not concerned about the energy consumption because that is circumstantial: I'm temporarily in a region that is getting almost no usable sunlight, it's below freezing even in the middle of the day so I'm my using my camper's furnace 24/7, and using some tools that are consuming more power than is typical. So I'm not getting back to 100% from solar during the day. But regardless of that, why would anything be draining my batteries at all while I'm connected to shore power? That's what I'm curious about. What is typical behavior of an inverter charger with LiFePO4 batteries when connected to shore power?

My expectation was that when shore power was connected, it would charge the batteries to 100% and then supply all power to AC/DC systems without draining the batteries. I would like to be able to show up to mooch dock or stop at a campsite with hookups to juice up the batteries, and then leave that site with 100% charged batteries for my next off-the-grid excursion. It seems that won't be the case unless I disconnect my batteries after reaching 100% charge. (the problem with that is it sends the inverter charger into an error mode and it sits there screeching its alarm until I turn it off or reconnect the batteries). So I have to keep the batteries connected even when on shore power.

I recognize that I'm new to this domain and have to let go of preconceived notions and expectations. This just really struck me as odd though.
 

gcp

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I would set it up with a customized setting not the preset li setting.

You don't say the size of your battery bank so it's hard to compare what 40% dod overnight at 12v while still plugged in have 120v passing through ac power and not inverting.

I don't have Renogy (using Magnum hybrid) but this is my experience or what I do with my system when connecting to shore power which isn't often as I fulltime boondock. System in signature. Bulk/ absorb 14.1v (absorb set for 10 minutes, last 6 minutes. Can't be turned off) "float" 13.6v. I use my system everyday. Magnum has the ability to individually shut off the charging, inverting. I'll set my incoming loadshare to what the power is plugged into 15a, 30a, 50a. I'll turn off the charging from the inverter/ charge while letting the solar top off the batteries the next day but the inverter is left on "sleeping" so if there is a power loss it just wakes up and takes over till ac power is restored.

Now all 12v items are being powered by the batteries and all other appliances are being power by 120v power. When the furnace runs alot during the night and other misc 12v items are being powered, the average depleted from the batteries is 30-60ah by the time sun recharges the small amount and keeps them topped off till nighttime or a power outage.
So I think you're saying that even when on shore power, your batteries are being depleted? That's pretty much the core of my question.
 

kenryan

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That's cumulative drain, not just in one night. I'm not concerned about the energy consumption because that is circumstantial: I'm temporarily in a region that is getting almost no usable sunlight, it's below freezing even in the middle of the day so I'm my using my camper's furnace 24/7, and using some tools that are consuming more power than is typical. So I'm not getting back to 100% from solar during the day. But regardless of that, why would anything be draining my batteries at all while I'm connected to shore power? That's what I'm curious about. What is typical behavior of an inverter charger with LiFePO4 batteries when connected to shore power?

My expectation was that when shore power was connected, it would charge the batteries to 100% and then supply all power to AC/DC systems without draining the batteries. I would like to be able to show up to mooch dock or stop at a campsite with hookups to juice up the batteries, and then leave that site with 100% charged batteries for my next off-the-grid excursion. It seems that won't be the case unless I disconnect my batteries after reaching 100% charge. (the problem with that is it sends the inverter charger into an error mode and it sits there screeching its alarm until I turn it off or reconnect the batteries). So I have to keep the batteries connected even when on shore power.

I recognize that I'm new to this domain and have to let go of preconceived notions and expectations. This just really struck me as odd though.
I completely agree with your expectations. Anything else makes no sense.
 
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Sojourner1

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So I think you're saying that even when on shore power, your batteries are being depleted? That's pretty much the core of my question.
They're being depleted because I chose to have that happen during the night and solar top off during the day.
I can leave the charger on and it will happily leave them at 13.6v using 120v (shore power) and did this the very first year of installation when in rv parks after switching over to boondocking and very rarely in rv parks now I just let solar handle the lite loads of 12v and with 1,280w on the roof it has to be a really crappy solar day for it not to cover under a 100ah in a day but there has been a few and turn off the charger now while on shore power.
 
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Sojourner1

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That's cumulative drain, not just in one night. I'm not concerned about the energy consumption because that is circumstantial: I'm temporarily in a region that is getting almost no usable sunlight, it's below freezing even in the middle of the day so I'm my using my camper's furnace 24/7, and using some tools that are consuming more power than is typical. So I'm not getting back to 100% from solar during the day. But regardless of that, why would anything be draining my batteries at all while I'm connected to shore power? That's what I'm curious about. What is typical behavior of an inverter charger with LiFePO4 batteries when connected to shore power?

My expectation was that when shore power was connected, it would charge the batteries to 100% and then supply all power to AC/DC systems without draining the batteries. I would like to be able to show up to mooch dock or stop at a campsite with hookups to juice up the batteries, and then leave that site with 100% charged batteries for my next off-the-grid excursion. It seems that won't be the case unless I disconnect my batteries after reaching 100% charge. (the problem with that is it sends the inverter charger into an error mode and it sits there screeching its alarm until I turn it off or reconnect the batteries). So I have to keep the batteries connected even when on shore power.

I recognize that I'm new to this domain and have to let go of preconceived notions and expectations. This just really struck me as odd though.
I don’t use a Renogy and glancing at the pdf it seems that while using the generic li setting it's turning off the charging/ float after getting them full. 14.7v is a little rich for my taste besides. Use a custom setting so it holds a float voltage.
 
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gcp

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I don’t use a Renogy and glancing at the pdf it seems that while using the generic li setting it's turning off the charging/ float after getting them full. 14.7v is a little rich for my taste besides. Use a custom setting so it holds a float voltage.
I'll give it a shot! Thank you.
 
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