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[GallenH]

I'm still struggling with my house battery: 105AH LifeLine purchased about 7 years ago. Has been living in AZ environment. I can't seem to get the battery up to what my Victron reports as 100% charge. That inability exists whether I'm driving or if I'm charging via converter at home. My latest readings are shown below.

VictronRead.png

On the left is the reading immediately after disconnecting home electrical from RV. On the right is the reading after letting the RV sit for 3 hours off of home electric. I know it's not the best evaluation but the volt readings correspond to what LifeLine indicates should be somewhere between 60-70% SOC.

Any ideas/observations most welcome
Glenn

[booster]

Originally Posted by GallenH

I'm still struggling with my house battery: 105AH LifeLine purchased about 7 years ago. Has been living in AZ environment. I can't seem to get the battery up to what my Victron reports as 100% charge. That inability exists whether I'm driving or if I'm charging via converter at home. My latest readings are shown below.

Attachment 14870

On the left is the reading immediately after disconnecting home electrical from RV. On the right is the reading after letting the RV sit for 3 hours off of home electric. I know it's not the best evaluation but the volt readings correspond to what LifeLine indicates should be somewhere between 60-70% SOC.

Any ideas/observations most welcome
Glenn

Are your pix swapped? How do you have more SOC after sitting than fresh off charge?


What it looks like off charge is not what you want to look at.


What you need to see is what is happening at the very end of your charge cycle to see if the battery is really full and if the charger is doing a good job of charging.


Lifeline defines a full battery on charge, as being at 14.1-14.4 volts and at .5%C amps so you would want .5 amps charging at that point. If the voltage is lower or the amps are higher, the battery is not full to Victron spec.


You monitor probably has history in it so you may be able to see that information in that history. Without knowing that there is no way to tell what is going on accurately.

[Uncle_Rico]

I recall your Victron monitor was misbehaving last year as well. On Victron monitors a positive current means current is flowing into your battery. Is there any charging source connected when these pics were taken? do you have solar? If not I still suspect you have an installation problem like the shunt is in backwards or maybe you're not capturing all of the return current to the battery bank.

[GallenH]

Right now RV is in shop having some chassis work done. When it gets back I'll run another series of tests. The ones posted are "immediately off charger" and "3 hours off charger." I did not run one while on the charger. Will this next time. But to answer your other questions, no solar connected. No charging source at all with the previous readings. And I've had this Victron monitor for several years. I think the most depletion it ever showed was down to 78% and, in the past, it aways got back up to 100% after charging on converter or driving or on solar. So I'm pretty sure that the shunt is correctly installed. Keep an eye on this thread. I'll update with new readings sometime this weekend. Thanks.

[booster]

Originally Posted by GallenH

Right now RV is in shop having some chassis work done. When it gets back I'll run another series of tests. The ones posted are "immediately off charger" and "3 hours off charger." I did not run one while on the charger. Will this next time. But to answer your other questions, no solar connected. No charging source at all with the previous readings. And I've had this Victron monitor for several years. I think the most depletion it ever showed was down to 78% and, in the past, it aways got back up to 100% after charging on converter or driving or on solar. So I'm pretty sure that the shunt is correctly installed. Keep an eye on this thread. I'll update with new readings sometime this weekend. Thanks.

I have said many, many times on this forum that with AGM batteries in particular, and with any shunt based monitor, you shouldn't believe the SOC % on the monitor until it is full calibrated by resetting based on volts and amps. That is where you always have to start in troubleshooting these systems because if you reference is point, everything you do after that is going to be wrong. 12.4v off charge and showing 100% SOC is not possible if the battery and charging are both good.

[Uncle_Rico]

Originally Posted by GallenH

Right now RV is in shop having some chassis work done. When it gets back I'll run another series of tests. The ones posted are "immediately off charger" and "3 hours off charger." I did not run one while on the charger. Will this next time. But to answer your other questions, no solar connected. No charging source at all with the previous readings. And I've had this Victron monitor for several years. I think the most depletion it ever showed was down to 78% and, in the past, it aways got back up to 100% after charging on converter or driving or on solar. So I'm pretty sure that the shunt is correctly installed. Keep an eye on this thread. I'll update with new readings sometime this weekend. Thanks.

Something is definitely wonky because with no charging sources present the monitor is showing about 0.9amps of charge current, the state of charge estimate is increasing accordingly (0.9 x 4hrs = 3.6Ah or about 3%), and the time remaining is showing "--" (i.e infinite) which means the monitor thinks the battery is accepting charge.

[GallenH]

Somewhat bizarre but I'm sure explainable. Got RV back from car shop yesterday and parked in dw without plugging in. Here's my morning reading.IMG_4009.jpg

We now have 100%..........however........the volt reading is 10.45. That's close to my old vo meter (10.51). That appears to be below Lifeline's spec for 0% SOC. (2nd) however: That reading is with the battery disconnect in "off" position. I'm thinking that I have to take everything off the battery posts and do a volt test with my meter to see what the reading is with absolutely nothing attached.

Make sense?

I'll also, after that, put my car battery tender on the naked battery for a day and see what I get on the meter then.

Any other suggestions?