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Batteries ok but voltage in batteries drop

Bambinoruth714

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I have got 8 gel batteries whoes voltage drop from full 51.1 volt to 47. i checked the batteries and they were at 12.7 disconnect. I keep them disconnected for a week and again checked them, they are ok. I have a schneider 4048 inverter, can anyone pleae help? . I think it a programming issue.
 
Can you tell me about what charge controller you have and what it's settings are? I have the 24V version of your inverter, the Conext 4024. You shouldn't be paying as much attention to your inverter as you should your charge controller.

Most likely your batteries are not being fully charged. If they are, then most likely they are too small for your application. Schneider recommends a battery no smaller than 100Ah for moderate loads, and at least 200Ah for heavy loads. Right now, my 4024 has a 568Ah battery, and there's no noticeable voltage drop.

BTW, if you want to test your batteries in the future, letting them rest a few hours is all that's needed. I would NOT leave them disconnected for a week.
 
Inverter schneider 4048, OUTBACK FLEXMAX 80 FM 80 MPPT 80 AMP, BATTERIES ARE RENOGY DEEP CYCLE GEL 12 V 200AH.
As I said I tested the batteries and they are jus t fine. All I use the equipment is in the AC SUPPORT MODE during the day. The voltage will fall with no use from 51.1 (full) to 48 volt. During a black out the system has failed. Thanks for your help
 
Inverter schneider 4048, OUTBACK FLEXMAX 80 FM 80 MPPT 80 AMP, BATTERIES ARE RENOGY DEEP CYCLE GEL 12 V 200AH.
As I said I tested the batteries and they are jus t fine. All I use the equipment is in the AC SUPPORT MODE during the day. The voltage will fall with no use from 51.1 (full) to 48 volt. During a black out the system has failed. Thanks for your help
In not a sunny day these are the reading in the out IN 118.8 V 1.8 A ,OUT 55.0 V 4.0 AKW 0.220 KW 0.9 KWH. The inverter reads as following BATTERY -2.9 A. 55.0 V, BATTEV E-F,LOAD 329 YY, AC1 247V. -183 YY. I hope this could help.
Thanks
 
In not a sunny day these are the reading in the out IN 118.8 V 1.8 A ,OUT 55.0 V 4.0 AKW 0.220 KW 0.9 KWH. The inverter reads as following BATTERY -2.9 A. 55.0 V, BATTEV E-F,LOAD 329 YY, AC1 247V. -183 YY. I hope this could help.
Thanks
Can you post a pic of this? I cannot visualize what you are looking at.
 
The inverter reads as following BATTERY -2.9 A. 55.0 V,
That appears to be saying you are using 2.9A from 55V ?

55.V is like 13.8 which is like bulk/float voltage for AGM

Post the pics like the wiser-than-me mrsandals requested and info michaelk asked about...
Too hard to guess what’s up.
 
OK, now that we know you have an Outback charge controller, let's focus some attention on the charge settings. Can you please tell us what the Outback is set to for "bulk", "absorb", and "Floating". How do those number compare to the manufacturer's recommended charge settings?

How many watts of panels do you have charging this system? A charging voltage of ~55V seems to me to be about 75-80% charged. In the cold winter weather, my charge goes up to 60V when the charge is reaching 100%.
 
I have got 12 320 solar panels attached to my system . I am sending you some photos, hope this helps.
 

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Nice system! Except for the Outback controller, your system looks very much like my workshop system. The only difference is I use a Midnight200 controller and the 4024 instead of the 4048. Looking at the Outback display, I see it charging at 50.5V. That is a quite low voltage for a 48V bank, and it's not the voltage I'd expect to see a fully charged battery reaching. I'd expect to see that voltage the first thing in the morning after draining the batteries overnight.

OK, do you know have to go into the Outback's charge settings to make changes? Did you find out from Renogy what your optimal charge settings are? My batteries are flooded lead-acid, and my charge parameters are B/A/F 59.6V/59.6V/54.0V. That most likely will NOT be exactly the same for your batteries, but it will be ballpark. I would go into the Outback charge settings, and start slowly ratcheting up the values towards the maximum that Renogy recommends.
 
I looked up the batteries parameters. I can't find or don't understand the TERM ABSORB I have been looking for it and can't find it . Does this term have another name? I also would want to know that once these changes are made in the controller, are there any changes that must be also made in the inverter? I forgot to mention that even on a sunny day I have turned off the power authorities electricity supply to the home (just once) and the system did not kick in.

Really Thanks and an a real amateur
 
It is the charge controller that decides what voltage the batteries charge at. The inverter only comes into play if you connect a generator to ACin and charge the batteries via generator power instead of solar. I went to the Renogy website and this is what I found for your battery.

Here is what I would do. Go into your Outback's settings, and check the bulk setting. That would correspond to the "Cycle Use Voltage" the the Renogy table indicates. For a 48V battery the numbers would be 56.8V to 57.6. Set the float between 54.4V and 55.2V. For now we can ignore Equilization. See what your controller is set to, and change them to match the settings recommended by Renogy. Start at the lower values, and inch your way up a few tenths every couple of days till you reach maximum. It doesn't look like a separte aborb setting is used here. Just set it to the same value as your bulk setting.
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