SOC when connected to shore power

JourneyingTurtle

Advanced Member
Joined
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Livingston
Please forgive my ignorance.

Should the State of Charge remain at or near 100% when connected to shore power?

2022 Thor Tellaro K
200ah lithium package

When plugged into shore power, the CombiMaster panel indicates “charging/float” yet the SOC on the Balmar panel decreases throughout the night.

I’m still learning how to read and interpret all of these panels.
 
No problem and that is what this forum is about so don't worry about a question like that!

SOC is "state of charge". It should probably take an hour or more to reach 100% SOC if your batteries are somewhat discharged. Think about SOC kind of like your car gas gauge. Any time your batteries are charging you should see the SOC going higher.

SOH is "state of health" or condition of your batteries.

You should also notice when you toggle through the Balmar functions by pressing the button + or - amps. That is how many amps are going into your battery bank or coming out depending on your electrical needs or charging status.

You should have solar charging on your van that works automatically. It will "trickle" charge the batteries and power the refrigerator but not much else.

You will notice some decrease in SOC at night because the solar is not adding anything to your batteries. The inverter does pull a small amount of power any time turned on so recommend just turning it off unless you need A/C power. You can turn it off at the panel rather than the toggle switch. That keeps your battery charger operational. Turning it off at the toggle also turns off the charger. The charger should work even if the inverter is turned off if done at the panel and not the toggle switch.

Everything you described sounds completely normal.

Hope that helps
 
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That all makes sense but I feel that I'm still missing something.

My expectation is that the SOC would remain at or near 100% when connected constantly to shore power. I've been plugged in for 3 days and the SOC drops as low as 65% every night. The SOC increases to nearly 100% during the day when the sun is shining. It appears to me that the batteries are not charging from shore power but perhaps my expectations are incorrect.
 
If plugged into shore power for three days your batteries should be at 100% SOC or pretty close unless something is wrong with them. However, since your inverter/charger was not turned on (toggle switch off) for some time period I would just make sure it has time to do its job. You should be able to see the power from the charger going into your batteries by noting the + amps reading on the Balmar display. The mastervolt display should also show that batteries are charging when connected to shore power. The mastervolt display is also where you can turn the inverter off instead of the toggle switch.
It would seem to me that your battery charger is working correctly because your solar panels do not have enough power to charge the batteries that quickly.

I made a few changes to my previous post so check it again as it may take a minute or so to "catch up".
 
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If plugged into shore power for three days your batteries should be at 100% SOC or pretty close unless something is wrong with them. However, since your inverter/charger was not turned on (toggle switch off) for some time period I would just make sure it has time to do its job. You should be able to see the power from the charger going into your batteries by noting the + amps reading on the Balmar display.
I made a few changes to my previous post so check it again as it may take a minute or so to "catch up".

The inverter was off but the charger was on. The toggle was set to charge only. Looking at the Balmar display right now I see -2.4 amps. Everything seems to indicate the batteries are not charging via shore power although the CombiMaster does say charging/float.
 
If your SOC right now is close to 100% then your charger is smart enough not to over charge them. If your SOC is say 60% or so then the battery charger should be charging/"bulk or absorb" and not float if connected to shore power. Charging/float indicates a very low charge rate ( meaning your batteries should be close to full). If not then you may need to get some technical assistance at a dealer. The batteries if damaged will not charge properly or if your inverter/ charger is not set up properly it could need to be changed.
 
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The inverter was off but the charger was on. The toggle was set to charge only. Looking at the Balmar display right now I see -2.4 amps. Everything seems to indicate the batteries are not charging via shore power although the CombiMaster does say charging/float.

Float charge with -2.4 amps is still possible if you have other sources using power on. If your SOC is close to 100% that still sounds correct. If your SOC is low ( 60 % or so) and showing float charge, then something is not right. Just out of curiosity what is your SOH showing on the Balmar? That should give you an indication if your batteries are bad. Also curious if you are plugged in to a 30 amp plug or a standard 15/20 house plug? If plugged in to standard house 15/20 amp plug you should/can adjust that also on the mastervolt display. That allows your charger/inverter to know how much current is available.
 
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Float charge with -2.4 amps is still possible if you have other sources using power on. If your SOC is close to 100% that still sounds correct. If your SOC is low ( 60 % or so) and showing float charge, then something is not right. Just out of curiosity what is your SOH showing on the Balmar? That should give you an indication if your batteries are bad. Also curious if you are plugged in to a 30 amp plug or a standard 15/20 house plug? If plugged in to standard house 15/20 amp plug you should/can adjust that also on the mastervolt display. That allows your charger/inverter to know how much current is available.

I am in the situation daily where the SOC is as low as 65% and the ComboMaster says charging/float.

The batteries do charge via solar and when the engine in running making me think the batteries themselves are fine.

I am connected to 30 amp shore power.
 
Sounds like something is not working as it should if at 65% SOC and float charging. I would try and turn off everything including the master rotary switch and disconnect power cord. Leave it off for a few minutes and try and turn everything back on. "May" reset the system. If doesn't work you may need some assistance. Could be the settings are wrong on the charger/inverter. I know the manual for that device shows "dip switches" that need to be set for correct battery type etc. but can't help much with that. If the SOH is showing a low percentage too could mean there is a problem with the batteries?? Probably a "long shot" but the dealer where you purchased it hopefully can help? My experience with dealers has not been positive but might be worth asking them? Unfortunately most of the dealers I have had experience with know very little about these.
You can also call Thor as they have a customer service number that can assist with technical issues like the one you are describing.

Sorry and good luck.
 
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Lithium batteries should not be stored at 100% SOC; closer to 60%. They also don't need to be float charged.

Lithium in an RV is a little different as there is always some load pulling current and frequently charging is available via Solar, SP (Inverter/Converter) and Alternator.

Perhaps the charger is smart enough to not keep the batteries at 100% for extended periods of time?
 
Agree that for storage float charge not necessary and best not to store 100% charged. However, his charger should do more than 65% and not be on float at that SOC. Mine goes to float when almost charged completely however to reach 100%. Would think at only 65% SOC charger should be in bulk or absorption mode.
As long as his is connected to power however would not expect it to drop down that low. At least mine never has and I have the same setup.
 
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GRV just changed my ATS ( Automatic Transfer Switch ) , seems it was not engaging properly or weak pull in coil ,bad contacts ,what ever , I had issues with no 120V power at all , not from SP or the LI Battery system , yet everything showed it was on SP .

I have plugged in SP over a doz. times & its been trouble free since .

I keep my RV plugged into SP all the Time when in the driveway & use the RV for errands several times a week , most of the time with the A/C ( inverted ) in back on for the Dogs & I keep the refrigerator on , because I like cold drinks ready.

Shouldn't the Inverter/Charger still charge the Batteries even if in just "Charge only" , if a charging source is available ,SP ?
 
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Please forgive my ignorance.

Should the State of Charge remain at or near 100% when connected to shore power?

2022 Thor Tellaro K
200ah lithium package

When plugged into shore power, the CombiMaster panel indicates “charging/float” yet the SOC on the Balmar panel decreases throughout the night.

I’m still learning how to read and interpret all of these panels.

"Should the State of Charge remain at or near 100% when connected to shore power?"... yes
check your shore power (unplug shore power), check your use/store switch.
 
"Should the State of Charge remain at or near 100% when connected to shore power?"... yes
check your shore power (unplug shore power), check your use/store switch.

Reference for your answer as it applies to coaches with the lithium battery pack?
 
Reference for your answer as it applies to coaches with the lithium battery pack?
When plugged into shore power, the CombiMaster panel indicates “charging/float” yet the SOC on the Balmar panel decreases throughout the night.
lithium or lead acid, doesn't matter
the batteries aren't being charged by the 120v :nonono: part of the syst
 
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A little bit more information.

I unplugged from shore power with the Balmar indicating 67% SOC. A few minutes later, I plugged back in and the MasterVolt panel indicated Charging/Bulk then switched to Charging/Absorption as expected. During these charge phases, the SOC increased. I did not see it at 100% but it was close. However, since it switched back to Charging/Float, the SOC has gone down and is back in the 60s again this morning.

I did confirm some of the dip switches on the CombiMaster don't match what are listed in the RV specs. I've reached out to Thor for confirmation before I start changing them.
 
Sounds like you are on the right track and hopefully something simple with your CombiMaster setup (dip switches).

Was wondering however what the Balmar is reporting as SOH(state of health) % of your batteries? Could be that your batteries are having a problem holding the charge? If that is the case, Relion (battery manufacturer) may be able to help with their warranty.

One other suggestion is to contact Mastervolt, the manufacturer of the Combimaster. I have not spoken with them directly but others have reported they are helpful and I am sure they could help you make sure your dip switches are set correctly and assist with other troubleshooting. They have a support page on their site where you can request technical support.

Good luck and look forward to finding out what may be causing your issues.
 
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Sounds like you are on the right track and hopefully something simple with your CombiMaster setup (dip switches).

Was wondering however what the Balmar is reporting as SOH(state of health) % of your batteries? Could be that your batteries are having a problem holding the charge? If that is the case, Relion (battery manufacturer) may be able to help with their warranty.

One other suggestion is to contact Mastervolt, the manufacturer of the Combimaster. I have not spoken with them directly but others have reported they are helpful and I am sure they could help you make sure your dip switches are set correctly and assist with other troubleshooting. They have a support page on their site where you can request technical support.

Good luck and look forward to finding out what may be causing your issues.

The Balmar is reporting SOH at 96%.

I did contact Thor and they provided me with the same doc I already had showing the dip switch positions. They would not, however, advise me to change them and directed me to a dealer instead. Unfortunately, I'm not having luck finding a dealer to take a look until December. I checked Mastervolt's website and it seems they also direct you to one of their dealers for tech support.

I'm so tempted to change the dip switches to match the docs but I just don't know enough about it to feel comfortable that I won't do damage.
 
The Balmar is reporting SOH at 96%.

I did contact Thor and they provided me with the same doc I already had showing the dip switch positions. They would not, however, advise me to change them and directed me to a dealer instead. Unfortunately, I'm not having luck finding a dealer to take a look until December. I checked Mastervolt's website and it seems they also direct you to one of their dealers for tech support.

I'm so tempted to change the dip switches to match the docs but I just don't know enough about it to feel comfortable that I won't do damage.

Take a couple of pictures of the switches BEFORE you make any changes!

How many and how many of the switches need to be changed?
Does your documentation show what each switch/position does?

You should probably take power off of the board :eek: before touching it :thumb:
 
There are actually only two switches that don’t match the documentation. One is for battery type and the other is AC Input Support. The battery type switch is currently set to “MasterBus” which is flooded unless changed from a computer. The specs say it should be set to MLI.
 

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