SOC Image

SOC

Disconnect BMW SoC depended relay function and discharge floor

Guys, there have been several request now cause there are numerous applications, where a user wants to switch devices based on the SoC, WITHOUT changing the discharge floor.


In my application, I want to use the BMV-700 relay to switch a large power relay to reverse IN/OUT of my Orion, to charge the starter battery as soon as the AUX battery SoC is above 95%. But in regards to the time-to-go, I want to leave the discharge floor at 25% (75% DoD).


I urge you to take these request into account when determining the scope of the next firmware update. Please !!

cstenger asked
cstenger edited ·

0 Answers

Confirmation of "static" SoC meter

Proud owner of a Victron BMV 700 in Canada and I need to ask a somewhat basic question.

Supposing I have a relay close/discharge floor set for a minimum state of charge (SoC) of 50%, and/or an alarm buzzer set for 50%, to avoid hurting my battery. Am I correct in understanding that the SoC screen and visual battery status indicator (the one that looks like a cell phone battery status) nonetheless shows an absolute reading between 0 and 100%? In other words, if I set up precautions to prevent discharge below 50%, the SoC indicator does not "recalibrate" such that "0%" equals my desired maximum discharge floor of 50%?

I assume the answer is no; "50%" SoC/half-full battery icon means the battery is indeed at 50%, and my discharge floor relay and/or buzzer will sound at this mark.

Thanks for the clarification.

jddh asked
Mike Dorsett answered ·

1 Answer

What is the correlation between SOC and Voltage?

I have 2 - 225ah 6v golf cart batt in series. My SOC is 85% and voltage is 12.09 as seen in this screenshot. Looking at the typical charge chart for voltage my battery should only be slightly Over 50%! Is there something wrong here? What am i missing.Screenshot_20210615-060831.png

adogbmw asked
dixonge commented ·

6 Answers

How to set depth of discharge

I would like to set a depth of discharge of 45% on my Quatrro inverter or color GX. In other words, once the battery capacity reaches 55%, then the system should either turn on generator or switch off. This is to avoid damaging my lithium batteries. Please can someone help to tell me how to go about it?

aliyuhussein asked
Kristof G. answered ·

2 Answers

SOC not shown on CCGX.

Hi.

We have a hybrid system with 6pcs Quattros on a 3-phase parallell system. We have MG Lithium-Ion LFP Batteries and a MG Master LV BMS. The Quattros are Connected to a CCGX on VE.Bus and the BMS on the VE. Can. Problem here is that I dont get the SOC from the BMS/Batteries displayed on CC GX.

Is there something I do wrong here?

[image]

[image]

[image]

orjolsen asked
Marcus Isaksson answered ·

1 Answer

BMV 712 Smart showing 100% when batteries are not

My Setup:

  • 200Ah ReLion LiFePO4 battery (recommended charged voltage 14.2-14.6V)
  • BMV 712 Smart
  • REDARC 50A DCDC Charger (Absorbsion: 14.5V; Float: 13.6V)
  • Victron 50/100 MPPT Smart (Absorbsion 14.5V, Float 13.6V)
  • Portable Power Tech 30A AC Battery Charger (Absorbsion 14.1V; Float 13.5V)


BMV Settings (as of now):

  • Battery Capacity: 200Ah
  • Charged Voltage: 14.4V
  • Discharge Floor: 20%
  • Tail Current: 1%
  • Charge detection time: 3 mins
  • Peukert Exponent: 1.05
  • Charge Efficiency Factor: 99%
  • Current Threshold: 0.1A
  • Time-to-go averaging Period: 3 mins


My Problem

I am not using much power, so my batteries rarely drop below around 70% SOC at the moment, but when recharging them the SOC never reaches 100%, and over time it drifts more out of sync to the point where after a month or so, it is showing ~95% as my maximum (it won't charge when the BMV shows SOC being 95%).

I know that you do have to calibrate the BMV every now and then, but with low power usage, a month to lose 5% SOC accuracy seems high.


My question

Do I need to adjust my BMV to any other settings? I cannot adjust my REDARC DC-DC or my AC Charger Float and Absorbsion Voltages (as far as I can tell). Any advice would be beneficial - TIA.

sam-strider asked
sam-strider commented ·

2 Answers

Multiplus stopped working after SOC reset on BMV 700

The Multiplus 24/3000 immediately stopped working after I had synced the SOC on the BMV-700 by pressing the "+ -" keys in normal operation. Since then it does not do anything anymore.

A hint to solve this problem would be highly appreciated.

Thank you!

chris-wy asked
chris-wy answered ·

3 Answers

250/100 not working right

hi my 250/100 is doing weird things,, it normally does 2.5 hrs in bulk, then 2.0 hrs in bulk . then float,, but now after a update sometimes it will go straight from bulk to float, then other times like now it says its buy the green light its in float but the history says its not in float? how weird,,, a new thing i completely disconnected this for 1 hr, no solar/no battery, then connected the batt wires , and got the right batt volts,, but it says the solar has 48 volts coming in, but no watts/dude there's no solar connected to the charge controller, i think you should have no volts if there's no solar connected? right

kevin-b asked
klim8skeptic commented ·

2 Answers

SOC differences between devices

System

Multi 48/3000 in a easysolar . MPPT 150/70 - 200 A AGM bat @ 48V - BMV

[image]

700- Color control.

[image]

I find the SOC shown on the BMV and Color control page wrong. See examples on attached pics. 96% to 97%

[image]

for 50.2 v does not seem correct.

The only location where I see a figure looking accurate is the 2nd page on the multi in the color control. 81%.

Any idea why would the SOC figures would show different values ?

Thanks

[image]

Herve RV Nizard asked
ishtiaq answered ·

3 Answers

Why does state of charge drop while voltage is high?

I have 200Ah of lithium batteries monitored by a BMV712. From fully charged batteries the only draw on the system is a fridge (I have turned everything else off) which draws about 3Ah. Overnight the SOC has dropped to 17% with a voltage of 13.3v. This situation happens consistently when I have been using the system in the past. I have reviewed my settings but perhaps I am still missing something there. Do you know of a reason why the SOC drops so quickly with very little load on the system?

colindernst asked
colindernst commented ·

2 Answers

Incorrect SOC reading

Hi, I have an Easysolar 48/5000 w. MPPT 150/100 charger. The system is working perfectly with the exception of SOC. My PV history shows that the batteries are going into float however the SOC continues to go down. When I put the generator on the SOC will instantly jump back to 85%. I’m really desperate to get an accurate SOC reading for the batteries. Is there a simple solution to this problem?

zenanuj asked
wetaelec answered ·

2 Answers

SOC won’t re-register

Ran boat batteries (4 6V series/parallel) down below 12V, charged back up to 13V but SOC won’t register. I dis and re - connected but still doesn’t register. Solution? Thanks

snowtanned asked
Paul B commented ·

2 Answers

Smartshunt Peukert calculation

Hello and good day to you all,

I'm considering using the Smartshunt 500A in a fair amount of boats so I did some testing. I setup the Smartshunt and a load. Started logging over VE-Direct storing the 'SOC' and 'Current' every second or so and made a nice graph. With the settings I made in the Smartshunt I tried to do the SOC calculation myself using the current and timestamps from the log file on the Peukert equation. I managed to get an exact match but only after I changed the 20hour discharge rate to 10hour (leaving the amount of Ah filled in with the Smartshunt and my equations the same). Can anyone confirm that the Smartsunt calculates "Peukert_t = dr*(Ah_rated/ (current*dr))^peukert_constant" ? where dr=discharge_rate=10 instead of 20.

I added the graph I made for reference. It has a load I changed a bit while discharging and added a little bit of charging at the end. I do regret rounding down the SOC numbers from VE-direct though.

[image]


orangedust asked
orangedust commented ·

2 Answers

BMV-712 State of Charge

Hi Everyone

I’ve a BMV-712 installed in our caravan which is fitted with a 100A/hr lithium. Using solar and DC-DC, as well as AC-DC charger. This morning the battery was sitting at 67%, charging ever so slowly on the solar. One minute later I noticed it had jumped to showing 100% SOC! I manually reset back to 67% but why would this occur and what can I do to ensure it won’t happen again?

Thanks Mark


mark-g asked
Paul B answered ·

1 Answer

BMV 712 State of charge configuration option disabled.

My battery bank cut off recently due to low voltage. As such I need to reconfigure the state of charge manually. Previously I could do this with State-of-charge configuration option to just set a percent. Now when i go to that option it is just two dashes and is not selectable. What is going on?


BMV 712 firmware v4.05

BMV Bluetooth interface firmware v2.23

Bootloader v1.10

daniel-chaffee asked
daniel-chaffee commented ·

2 Answers

Using BMV712 SOC to trigger Multiplus DC Input Low Shutdown without GX Device

Hi I'm looking for some help to understand the best way to trigger the DC Input Low Shutdown on my MultiPlus 3000VA from the BMV712.

I am off grid, solar charging Lithium Smart batteries with an MPPT 100/50, and use a small inverter generator to feed the MultiPlus when solar charging is insufficient.

I would like to limit battery discharge to 15% to maximize the life of the lithium smart batteries.

I've tried tuning the DC Input Low Shutdown voltage settings in the MultiPlus but found too much variability in the actual SOC when the DC Input Low Shutdown is triggered. For example, when a relatively short duration, heavy AC load is applied to the MultiPlus, the DC voltage will drop, triggering the DC Input Low Shutdown at a SOC much higher than if a small continuous AC load is being fed by the MultiPlus.

Attempts to use the battery monitor function of the MultiPlus and the corresponding SOC functionality to trigger shutdown did not work because the MultiPlus SOC is not accounting for the MPPT charge current.

Thank you

abegweit asked
jordash184 commented ·

2 Answers

shutdown on SOC vs Dynamic cut-off ESS + LITHIUM BATTERIES

hello guys,

we have a Victron system with Victron LiPO4 batteries installed the system is operating with grid-connected to it and in ESS mode, I made all the configuration with Ve Config, and I have one concern that is about the battery SOC and when to shut down the system depending on this.

there are two parts in ve configure related to the battery, the shutdown on SOC and the DYNAMIC CUT-OFF, I actually don't get the difference between them or which one will overcome the other.

[image]

[image]

I know that the cut-off is related to how fast the batteries are being discharged and to prevent continuous high discharge but I would like to shut down my batteries at 20 % soc whatever the discharge current is so if I set SOC shutdown in ve config to 15% with this overcome all the dynamic cutoff settings and shutdown at the 20 SOC%?


and how will this SOC level be calculated I already have Victron smart lithium batteries with VE-bus BMS and GX-color control that is showing the SOC of the battery, will the system consider this reading all I should install and extra BMV.

I attached two photos of ve configure part dynamic cut off and SOC shutdown parts

eyub asked
eyub answered ·

1 Answer

Multiplus with VE.Bus Smart Dongle reading SOC from a SmartShunt

Can a Multiplus get the SOC from a Smart Shunt through a VE.Smart Network using a VE.Bus Smart Dongle?

Roberto Kruse asked
Matthias Lange - DE answered ·

1 Answer

Feature request: Cerbo GX DVCC to also share SOC from BMV to Multiplus

Many of us have systems with a BMV battery monitor, a VS device such as a Cerbo, a Multiplus and other charging sources which the Multiplus ignores in its SOC calculation. Often in these systems, such as a boat, the Multiplus is often not used for charging when away from shoreline so it's DOC deviated badly. The Multiplus firmware has the ability to shut the inverter down at low SOC which is a good feature, but in the above scenario quite useless. In the system above, the Multiplus would benefit from being able to use the BMV SOC is shared SOC was programmed as part of DVCC.

pwfarnell asked
bathnm commented ·

2 Answers

from 70% to 10% SOC at once
hi everyone , i have :
200ah 12 lifepo4 x2 batteries on my boat
victron multiplus 12/1600/70
victron bmv 712
victron gx touch
last time i used my boat was about 10 days about, when i left it it was showing 100% soc, according to the voltage history it showed 13.3v back then
i have a daily consumption of about 12a per day from a gsm router that is working there 24/7
boat is on a drystack so no solar or any shorepower on there
since i left the SOC was going down a bit every day as shown the graph
but tonight the S0C went down from 70ish to 10% , which of course triggered the alarm.
trying to understand why this happened ?
i was told by the dealer i should only look at the voltage and not the SOC , and that the battery hasnt been full in the last 30 days .
where is the issue here then ?
should my battery reach 14v when full ?
i charged it up fully and its showing 100% SOC now and voltage is 13.5v
reason im asking is if my batteries are 200ah each, so 400each as they are in parrallel , then 12a a day should be around 120ah less until today, so still should be very far from even 50% capacity, what am i missing here ? am i looking at this wrong ?

Doron Azulay asked
H.W.Oelofse answered ·

1 Answer

BMV Not Detecting charge from Vehicle Alternator - Genisys Dual Battery system

I have a 712 BMV. I have it working in combination with a Genisys Dual Battery system for Jeeps. It works great and detects a charge if I charge my batteries using my solar (100/20 MPPT Victron charge controller ) which is connected to the ACC Power bus bars. When I drive the car however, the BMV never changes/detects the SOC regardless of battery voltage or Output (negative)... the SOC continues to drop...

The solenoid (in the picture) joins the 2 batteries when the starter battery ( the one on the left) is over 12.8 volts.

Attached is a diagram of the device and they way I have it hooked up.

Can any one explain why it will not detect the charge from the cars alternator and/or potential fixes?

thank you in advance.

[image]

jlursocal asked
Murray van Graan commented ·

2 Answers

ESS SOC LIMIT

Hi,


I try to set my Minimum SOC to 70% but the active SOC limit won't allow me to go lower than 80% on ESS

Any recommendations to set it lower?


[image]

hdp asked
Matthias Lange - DE answered ·

2 Answers

multiplus SoC not syncing to 100% (mains backup system)

Hello,

I have a system with:

1 x MultiPlus 24/3000/70-50 firmware 476 (but problem predates this firmware too)

4 x Trojan SAGM 06 375

for mains backup.

----------------

Edit 2020-11-24

Having clarified a few things since first opening this post I'm listing here the key points as I see them:

The system is not triggering a bulk/abs cycle after anything except a very deep discharge. I.e. it returns straight to float after small to medium discharges.

This means that over time, with several small/medium discharges the SoC indication gradually drops off, when really it should return to 100% once mains returns after such discharges.

I have been told that, by design, the bulk/abs cycle is triggered when the battery voltage drops below 26.2V (2.6V, for 24V systems, below the set absorption voltage of 28.8V). This is happening here, yet the bulk/abs cycle is not activating.

----------------

Original post:

The SoC indicated by the system will not sync to full for long periods of time, which results in the system always showing well less than 100% even when in float. Please see the VRM screenshot below.

I raised this issue somewhere on Victron community/disqus a good while back, but can't find it anymore! We never got a resolution, but I recall it was discussed that the reason was:

i) the battery voltage doesn't drop low enough under the brief discharges/small loads to trigger a full bulk/abs cycle (the SoC does reset to 100% on the rare occasions this does happen).

ii) the repeated absorption feature (which is set at every 7 days on this system) does not trigger a SoC reset on completion

I'd be very grateful for any ideas on how to resolve this, especially now as the system is using the new "shut-down on SOC" feature, which means the batteries will be cut off sooner than necessary due to starting with an already low SoC.

Many thanks

[image]

Edit 2020-11-02

I've added vrm screenshot to compare charts for the same mains failure event for this system and another very similar system (only differences I can think of are 48Vnom/375Ah vs 24Vnom/375Ah and CCGX vs venus GX). This system goes straight back to float, other system goes through bulk/abs cycle.

[image]

Edit 2020-11-24

Just adding another screenshot here as we've had some interesting events over the last three days. Of note is how a bulk/abs cycle was triggered by the full discharge to 40%. However, the most recent discharge to 80% didn't trigger a bulk/abs cycle. I'm wondering if perhaps somehow this system has the bulk/abs cycle voltage level trigger of a 48V system even though it is a 24V system?

[image]

colin asked
colin commented ·

2 Answers

BMV 712 SOC reads "--", Inverter reads "lo", No BMV history

I'm converting a Ford Transit 250 into a camper and just finished setting up my electric system last week.


Components:

BMV 712 Smart Battery Monitor

MPPT 100v 30A Solar Charge Controller

(3) 100Ah LiFePO4 Battle Born batteries

Giandel 2200W Pure Sine Wave Inverter

Sterling 60A B2B Charger

Progressive Dynamics 60A 12v LiFEPO4 Battery Converter/Charger


I've been reading forums and doing a lot of research and can't figure out why the Battery Monitor state of charge just shows 2 dashes (--), and there's no history (Deepest discharge - 0Ah, Discharged Energy 0.0kWh, etc.). It's been this way for about a week now.


Also, when I turn my inverter on, it beeps continuously and says "Lo", indicating low voltage protection. Yet my 12v system runs and works fine (water pump, lights, fan, etc.). But when I turn the inverter on to use my GFCI outlets, they don't work. And again, I can't tell what my SOC is.


I've gone through the battery settings in the Victron app and changed everything to the recommended specs (see attachment).


Could anyone please point me in the right direction?


Thank you!

[image]

[image]

joycarlaina asked
joycarlaina commented ·

1 Answer

Active SoC stuck at 80 %

Hi! I have a question regarding the functioning of the parameter 'Active SoC limit' that can be found in the ESS. While in mode 'Optimized (with BatteryLife)' I started playing with the different parameters to test the installation, and in particular with the parameter 'Minimum SoC (unless grid fails)'. At first, both 'Minimum SoC (unless grid fails)' and 'Active SoC limit' had the same value, but after increasing the value of 'Minimum SoC (unless grid fails)' up to 100 %, the 'Active SoC limit' became stuck at 80 %.

I would like to know what does this parameter 'Active SoC limit' really mean and what's the functioning behind, so I can have a better understanding of it once I change the value of 'Minimum SoC (unless grid fails)'. I have already read the ESS Manual but it is not very clear to me yet.

I would like to add that my installation works mainly disconnected from the grid except in a few occasions that it is connected for short periods of time. I don't know if that has anything to do with the system recognizing this and, thus, trying to set a high value according to this characteristic.

Thanks!

inigodu asked
Hendrik Coetzee edited ·

2 Answers

Batteries apparently losing charge on light load

This is a new installation set up using default settings on smartsolar and multiplus II.

When first connected, Colour Control GX showed battery charge at 85% if memory serves. Over the course of three weeks, battery SOC indication has dropped to 30%. Apart from two very brief higher load scenarios (vacuum cleaner for 5 minutes and fridge freezer for 2 hours) the only load has been the base load of about 5-7W (according to colour control).

Colour control is recording voltage of 55+ Volts on the 48V AGM 230Ah battery bank (confirmed by meter on the battery terminals), so the smartsolar will not do an absorption charge for very long (1 hour on default) before reverting to float.

As I write this, it is 11:32am, bright sunshine, and VRM is recording a 9W AC load, batteries idle 11W, SOC 29%, 55.4V and current 0.2A, and PV charging at 50W.

What am I missing?

20871pault asked
20871pault answered ·

3 Answers

What happens when BMV712 sees charging beyond 100% SOC?

I have a BMV712 + MPPT 75/15 in my new RV, and I've been collecting data through various conditions. After a lot of analysis, I'm convinced Johannes's video from earlier this year is providing the 'best' settings for my solar scenario, where I'm setting Charged Voltage = 14.2V (14.4V absorption minus 0.2V) and tail current around 5%. The downside is that we will synchronize when we're at approximately 95% actual SOC, and if we charge exclusively via shore power (which has a lower 13.8V absorption voltage), we will never synchronize. Setting lower tail current is not an option because we don't always stay in absorption mode long enough to see this lower current, and we don't want to set a lower charged voltage + lower tail current in float mode because clouds could result in a false synchronization.

So on to my question: when we synchronize, whether it's manually or automatically, we often will do so at a level slightly below the actual 100% SOC. What happens if we continue charging (regardless of whether it's in absorption or float) beyond this point? Specifically, will the BMV start counting down from 100% SOC after that additional charge is discharged? Or will it ignore that additional charge and just start counting down as soon as it sees any net discharge on the battery?


Here's an example:

- 200Ah battery, charged to 95% (190Ah), and synchronization event happens, setting the BMV to 100% SOC.

- Since we're not 'truly' at 100% (but rather 95%), an additional 10Ah of charge continues to be applied before true float/maintenance state reached.

- After that point, we apply a load that consumes a net 5Ah power off the battery.


What's the BMV going to indicate?

- Will it internally calculate that we're at 100% + 5Ah capacity (effectively, 102.5%) and keep displaying 100% SOC until we've discharged more than the 10Ah "extra" we added post-sync?

- Or will it ignore that extra 10Ah of additional charge and just show that we're now at 100% - 5Ah = 97.5% SOC?


In simplified terms, when does the BMV start counting down from 100%, and how does the BMV handle additional charge beyond what it thinks is 100% SOC?


My guess is that anything above assumed 100% SOC is ignored/clipped, but the engineer in me wishes there was a way to better reflect 'true' SOC rather than jumping to 100% SOC when we're in reality only around 95%. The quest for accuracy :)


Thanks!

Tom

Tomasz Czernecki asked
rslifkin commented ·

1 Answer

SmartShunt SOC synchronization with SmartSolar MPPT

I know! This question have been asked before, and I think I have read every answer twice...and I am still not able to get my system to behave as I want.

System consists of 2x24V 100Ah LiFoPo4 batteries wired in parallel, SmartShunt, SmartSolar Charger MPPT 100/50, MultiPlus-II 24/3000/70-32, Cerbo GX and some other bits that are not important here.

I tried to configure the SmartShunt as per. the manual:

Charge Voltage: 26,7 ( SmartSolar float - 0,3v)

Tail Current: 2%

Charged detection time: 3 minutes

But this resulted in SOC resetting to 100% every morning when the SmartSolar started charging.


Based on the description of what the parameters does, and the graphs I could pull from vrm, I then tried to set the charge voltage to 28V and lowered the detection time to 2 min. But now the SOC does not reset even when the SmartSolar is done charging.

Below are graphs of such a scenario:

[image]

I do not understand why the SOC was not reset to 100% when the voltage was >28V and amperage was close to zero for many minutes?

Settings for the SmartShunt are:

[image]


Settings for the SmartSolar are:

[image]


I hope you guys can help here, because I don't understand it :)

bomadsen asked

0 Answers

How to set SOC charging target other than 100%?

My system has 2 Smart Li 200Ah batteries, Multiplus 3000/120, 2 MPPTs 100/30, connected via BatteryProtect, Alternator connected to AGM, and via Cyrix Li to Li batteries. Setup includes BMV-712 Smart and Venus GX.

I want to be able to charge the batteries to say 60% or 80% only while on shore power, knowing that I will have plenty of sun for the rest of the day.

How can I set an SOC target for the Multiplus, or better via Venus GX? I don't want to change the absorption/float voltages.

kupo asked
hackett answered ·

7 Answers

Inaccurate readings?

[image]

Trying to understand and get a descent battery reading since I installed this BMV-712.

I added a RPi 3b+ with VenosOS for monitoring.

Attached is the latest readings from this week.

The numbers don't make sense to me.

I have two golf cart batteries (230Ah each) in series, so 12v with a useable 230 amps (Right?)

So if I have used 82 amps of the 230 as stated by the monitor shouldn't that be 64%, how does the monitor calculate 78%?

Is there a setting to mitigate this error? A setting I've missed?

Also, the (mostly) at rest voltage is 12.17 volts? Is this not considered a battery at roughly 50% charge?

(There are parasitic loads in the trailer, fridge, CO2 Dect. ect that I cannot remove)

I was hoping that this 712BMV help me determine the state of my battery, but I'm as confused as ever!

I just want to get the most out of the batteries without damaging them early.

Attached is the last week of use. battery started from full. Zero Cal was done with everything disconnected with the exception of the BMV itself.

mogal asked
mogal answered ·

2 Answers

Followers

254 Posts
222 Users
6 Followers

Topic Experts

ascherg
0 Points
Sabrina
0 Points
Koul Alim
0 Points