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
lelandjohnston answered ·

6 Answers

How can I set custom SOC in my Multiplus C 12/1600/70 without using VE config?

I have lithium batteries in my boat and do not want to charge them to more than 85% SOC normally except when I plan longer trips and want to top them off to 100%. Is it someway I can change that through either VRM or via Cerbo and Touch 50 without using VE Config? Would be a nice feature to have for managing lithium banks. Custom SOC and then shut off the charger when SOC is reached. Second feature would be to have the auxiliary charger on for maintaining current to the AGM starter battery bank.

trulsla asked
Alexandra edited ·

1 Answer

How to see SOC on Easy Solar 24/3000/70-50 MPPT Colour Control Inverter Charger system

I have just had a Victron EasySolar 24/3000/70-50 MPPT 150/70 Color Control Inverter Charger System installed in an off grid setting, trying to make sense of the manual [which says for a multiplus so poss wrong manual? or is the EasySolar a MultiPlus?] though there is also a Smart Solar charge controller manual, [lists lots of various mppt] but can't really make any sense of this either. Basically would really love to be able to work out how to see the batterries SOC [state of charge] which is how I used to guage my old system, Firstly on the Color controller GX, Then I think I have connect to it online but can't fathom that out either, not sure if I some sort of wifi dongle {where would I plug it in as the color controller is attached to the inverter/charger] or plug in an ethernet cable? I have been trying to research it from the Victron site, but so many pages link to other pages that don't seem to function & I am getting more confused.

We used to have a 12 volt system & this one is now 24 volt so also quick question, before I could gauge my batteries by the dc voltage [Not wanting it to go below 11.5] now as this is a 24 volt system on the color controller in the bottom left hand battery icon, its states around 25.1 v -1.4A [fluctuating] is the 25.1 v the battery voltage as its on a 24 volt system [so 2 x 12 would be 24] so 25.1 is Ok & I guess if it goes down to 23v this would be equivilant on 11.5 on a 12 volt system.

It seems such a shame that there doesn't seem to be any guide on the victron site or in the manuals what this wonderful colour controller images mean! for non tech savvy folks like me

Thanks in advance

lucylite asked
Alexandra answered ·

1 Answer

EasySolar-II SOC keeps falling and never rises?

Recently commissioned a EasySolar-II 3kva 48v system running PowerPlus Energy 4kwh ECO module. Setup battery monitor on VEconfigure, programmed mppt as per powerplus recommendation and all looking good. About 5 days later system shutdown on low SOC cut-out, went to site and batteries full and on float but SOC showing 15% so it had slowly gone down each day after i left but was in fact being charged fully each day. Where have i gone wrong??

mark-dreyer asked
on2itmaclennan answered ·

3 Answers

State of charge

Hello ,

I have MultiPlus Compact 12/1600/70-16 + Smart Solar MPPT 100/50 all in one.

Im monitoring system on GX display.

Everything is connected and it works good, but i have problem setting state of charge?

Is it possible to have state of charge with this configuration, or i need to install shunt?


[image]

T

nevercarry asked
nevercarry answered ·

2 Answers

Does the Relay Assistant in a MultiPlus Compact (aka Phoenix 12/2000) continue to work after low SOC shutdown?

Hi there,

I would like to be able to turn a MultiPlus Compact (Phoenix 12/2000) off when reaching a defined SoC. This part is easy. I would however also like to continue to use the programmable relay in the same MultiPlus to turn off DC loads via a Battery Protect when the SOC reaches a (lower) threshold. In other words, what I have in mind is turning off AC loads at say 25% SoC and turn DC loads off (relay driving a Battery Protect) at 15% SoC.

Is that possible?

Jan

jbakuwel asked
jbakuwel commented ·

0 Answers

SOC DIFFERENCE

I have a cerbo and a Lynx shunt on my BMS. The data says in a 24 hour period I have 1.3 kwh of solar and 1.1kwh of consumption so more power in than out, my SOC at the start is 77% and at the end 73%. How can the SOC reduce if the consumption is less than the solar generated ?

paul-clingan asked
Stefanie answered ·

1 Answer

SOC and Tail Settings

I added two photos showing the SOC went to 100% very quickly and was thinking I might need to change the settings for the tail percent?

2x SLR125 125ah agm batteries

Battery size = 250ah

Charged Voltage = 13.1v (thinking of changing this to 13.2)

Charge Time = 3m

Change Tail = 4% (not sure about this one)

[image]

[image]

[image]

burnttech asked
burnttech commented ·

1 Answer

BMV SOC just does not add up (or subtract) what is wrong here?

Setup: I have a BMV 700 On my boat with 300Ah (@C20) batteries, a pretty constant load current of 1A and an MPPT recharging the batteries when there is enough Sun.

The BMV SOC and Ah consumed values disagree by approximately 50% which is worrying because if the trend is across the full capacity the battery could be empty when the SOC says 50%.

I dont think it is anything to do with the setup (wiring to shunt etc.) as all I am looking at is the BMV data (see graph below) the BMV is reading the current (in/out) and making the calculations on this data so it is just not in agreement with itself. I would be happy to understand where I have gone wrong and learn from my mistakes, here is my reasoning.

I have read the article here.

https://community.victronenergy.com/questions/58699/bmv-700-soc-percantage-does-not-match-to-the-used.html

But I started a new thread as this is new data and I think it might be proof that something is not right (or I dont understand). In that article it says it might be the Peukert exponent but it is set to the Victron default 1.25, charging efficiency default 95%, battery capacity set to 270AH which is the C20 capacity less 10% all as set my my Victron installer. So if I am following Victron recommendations what more can I do?

Considering:

1) The load at 1A is so low that Peukert should not have any effect (which is about inefficiency when drawing high currents).

2) The problem can't be charging efficiency because the SOC is too high even when no charging has happened.

3) it cant be the wrong current reading because the BMV is using the current reading as its only input value for all the calculations. (it could be wrong but it should not be inconsistent)

4) it can't be the battery capacity setting that throw the readings out by 50% and anyway I have only entered the one capacity value so the BMV must base all its calculations on the capacity I have set (270 Ah).

5) Finally it should not be the discharge floor setting (15%) as setting a discharge floor should cause the SOC to be lowered for a given AH consumed value. Anyway according to the documentation discharge floor only impacts the time remaining.

BMV is Firmware version 3.11 - it was installed by an authorised Victron installer.

OBSERVATIONS

At the end of charging yesterday afternoon the BMV reset to 100% SOC and 0Ah used. Then 14 hours later this morning before the MPPT started up the values were.

  • SOC 98%, (actually looking via the VRM it gives the SOC at 97.6%)
  • Consumed 12.9 Ah,
  • Current -0.9A

The current was constant at between 0.9 and 1 A overnight, so I feel I can trust the consumed Ah. But the SOC at 97.6% suggests that 2.4% has been consumed and 2.4% of 270 is 6.5 Ah almost exactly half of the displayed consumed Ah.

The other suggestion in the article above is that it is rounding errors so I looked back through my data, as I took screen shots of the BMV display on my smart phone at intervals over the last 2 months.

Here is what I see:

The orange line is the % consumed calculated based on consumed AH (according to the BMV), the blue line is the corresponding line for 100%-SOC% (I.e. how much the BMV SOC says has been consumed). The lines are amazingly straight and as you can see the SOC is consistently saying that the amount consumed is half of what the consumed AH says.

[image]

IF anyone want to check here are my battery setting in the BMV.

[image]

My ultimate worry is that others who use the boat from time to time may rely on the SOC display and run the battery down without realising.

laurenceh asked
laurenceh commented ·

1 Answer

Soc 100% at absorbtion beginning

Hi folks!

On my system, SOC reaches 100% about 1 hour before the end of Bulk while full sun at 10:00. I thought that Bulk could only fill 80% of the battery capacity and that absorption was designed to fill in the remaining 20% and reach fuil SOC. I set BMV with the C20 Ah capacité Where am I wrong?

Lionel SEYDOUX asked
michelg edited ·

5 Answers

Battery SOC 100% but still charging?

Hello


In a solar system i have 2 packs of both 4 exide 330A gel batteries. Together this forms 2 sets of 24 volt batteries.

This setup is charged by solar panels connected to a MPPT 150-60 and a Multiplus compact 12-1600 is connected as well.

The system is monitored by a BMV 700 and this is connected to a color control gx.

Settings for the BMV are:

- Ah 660

- charged voltage 28,4 volt


My question:

Why the BMV tells the battery is 100 percent charged while the voltage is around 26,70-26,85 and still charging around 8 amps??


Shouldnt voltage readout be like around 28 volts and charging amps around at max 0,5 or so?


ThAnks in advance!


Best regards, Piet



piet-hein-van-asselen asked
piet-hein-van-asselen answered ·

4 Answers

Feature request: Dynamic Grid-Setpoint in ESS, based on top SOC.

Currently the Grid-Setpoint in ESS is a static number (in watts) that controls how much system power is allowed from grid, with the remaining load being served by incoming solar and/or battery capacity, down to a tolerable SOC. While that works great in the assumption of keeping batteries @100%, every day, it’s not so good for long-term health and maintenance of lithium batteries, in a (stable) grid-tied system.

I would like to suggest an upper limit to the SOC (other than default 100%), at which point the ESS would dynamically shift the load more/less (by changing Grid Setpoint) to charge the batteries when they’re below the high mark, and otherwise running the load off of solar or battery capacity, down to the existing minimum SOC (as normal)... or similar type of functionality.

Currently, I’m constantly changing the Grid Setpoint down, to serve the system loads from the incoming solar preferentially, as much as possible. Then resetting it up again at night, to keep the batteries above a reasonable SOC. While workable, it is way more manual than it needs to be.
I believe adding a simple top SOC to the algorithm that controls when to shift to using solar would greatly simplify and automate this process.

geomz asked
Alexandra commented ·

0 Answers

State of Charge never gets reset - BMV700 with MPPT 75/15 and 110W Solar panel

Hi, Sorry if this is a common question, I'm very new to Solar and trying to learn. I'm very impressed with my Victron gear but there is 1 problem.

I watched the Victron video explaining to change the BMV settings and have done so however the SOC detection still doesn't seem to be working...hope someone can offer some advice.

Setup:

120Ah "Fusion" brand battery

110W Solar Panel

BMV 700

MPPT 75/15

0.8A load

VenusOS on a Pi 3B+ with 2 x USB to VE Direct cables

The battery seems to be charging fine, I can see bulk then absorption then float phases. Unfortunately the SOC never gets reset at all, it just gradually declines until it's zero.

I haven't changed anything on the MPPT, it's by default at Factory default "Gel Victron deep discharge 2".

The BMV I have these settings:

Battery Capacity: 120Ah (I changed this)

Charged voltage: 13.5V (I changed this)

Tail Current: 4% (default)

Charged Detection time: 3m (default)


I set the charged voltage at 13.5V because I can't find the battery stat for this on the manufacturer's details so I looked at the average figure during absorption phase, 13.8. Based on this I set charged voltage at 13.5, 0.3 below absorption rate per video instructions here:

https://www.youtube.com/watch?v=4ReljfO3k6M

I guess I must have misunderstood something, can anyone help?

Thank you.




Dominic asked
Dominic commented ·

3 Answers

Grid SetPoint and SoC

Hey guys,

Very Quick quesiton. If I set grid setpoint as a -ve to discharge battery when spot price is high, can I rely on the SoC setting to stop discharging when the batteries get too low?

What one takes precidence?

Mike

Mike Casey asked
Mike Casey commented ·

1 Answer

Simulateur de SOC raspberry

Bonjour à tous

Afin de tester le bon paramétrage d'une installation PV, j'imaginais utiliser un "simulateur de SOC" . Quelqu'un a t il déjà fait cela ? à l'aide d'un raspberry par ex ?

Merci d'avance

denis-esf asked

0 Answers

2xBlue smart IP22 charger 12/30 (3) parallel on LiFePo4 questions

Usecase: REC ABMS connected to 12x 272Ah cells (Lishen), 3 parallel and 4 series (12V). Charging with 2x Blue Smart IP22 30A, Smart Solar 75/15 and TS800C-50.

The manual of the Blue smart IP22 is very limited with respect to its behavior of the "Lion" setting. First it doesn't feel right they call it "Lion" while LiFePo4 is a total different chemistry, but as they put LiFePo4 between () I assume this mode is for LiFePo4. Anyone that can confirm this?

Can someone explain how the charger behaves in the "Lion" mode?

I want to parallel two of these chargers. Is this going to cause any problems? Do I need to use the "Lion" mode or is it better to use the power-supply mode when putting in parallel?

From what I understood (e.g. https://marinehowto.com/lifepo4-batteries-on-boats/) LiFePo4 is very sensitive to overcharging. Even with low voltages (~13,5V) the battery can be killed when current is applied after 100% SoC is reached (very low internal R). So it is very important to stop charging when the current does reach a certain threshold (ideally SoC based), or to control this externally using a BMS. Anyone that can comment on this?

joep asked

0 Answers

SOC calculation worse with latest Multiplus firmware

First, let me say that I understand that, for my setup, the Multiplus's calculation of SOC will inherently be incorrect.

(Right now I have my battery bank being charged by both my Mutliplus and occasionally by my SmartSolar MPPT. So the Multiplus cannot see the current being fed to the batteries by the MPPT.)

Still, the SOC calculation was better with the firmware immediately prior to v481 that is now.

And I think it can be "hacked" to do better, as below.

Consider the following two screen shots, taken at two parts of the day.

[image]

This first shows the battery voltage is 26.56V and the SOC is 57%.

Now, as the day progressed, with solar charging, the battery voltage has increased to 26.82V. But the SOC has decreased to 31%!

[image]

I know that this incorrect SOC calculation is because the Multiplus is (apparently) looking at current only, and has seen 7 to 8 Amps leaving the battery all day, but is not seeing current coming in from my MPPT.

But as I said above, the previous firmware of the Multiplus handled this situation better.

Might I suggest a software hack, that when the battery voltage increases, the SOC calculation be prevented from displaying lower? That would solve the false low SOC reading in this case.

pmikep asked
pmikep commented ·

3 Answers

How to get Plyontech batteries to 100% SOC

Hello

My system is 2 x US3000 batteries, 1 x Multiplus II 5kw with a 1kw ongrid connected to the AC IN (waiting on stock of a BlueSolar) and a Cebro but I have an issue that the Cebro gives me a high battery voltage alarm with 91% 92% SOC and the charging stops... I can clear the alarm and sometimes it will go back to charging the batteries with 10 amps but that only lasts a minute ( if at all) so for now I cannot get near 100% charge. Any ideas thanks .

davidrkennedy asked
seb71 commented ·

2 Answers

BMV and discharge floor impact on SOC reading

Section 3.4 of the Victron BMV-7xx manual says "The battery state of charge indicator scales between the configured discharge floor and 100% state of charge and reflects the effective state of charge."

Is this saying the discharge floor setting does impact the XX.X% SOC display and/or the battery-fill [====] display?

The BMV manual seems pretty clear that the "discharge floor" setting DOES impact the "time left" display. The BMV manual seems contradictory if the "discharge floor" setting impacts the SOC and battery-fill displays however.

Thanks,

--tg

siletzspey asked
Stefanie answered ·

2 Answers

SOC vs Voltage

High in the southern french Alps, my house is powered by 2kWp on the roof, 30kWh OPZS lead batts and a 3kVA generator all manages by a full Victron system. The last 3 months the sun has been scarce and erratic but I kept my Multiplus 24/5000/230 running to keep a fridge and a congelator running as it is good to have something under your teeth after a 2 hours climbing in the snow. Max watts 150 when both run, but as the room temperature is about -4°C it should be for very short periods with a daily load under 1 kWh/day .

Q1: But on VRM, the voltage stays very low: Yesterday afternoon 24.77 for a 100% SOC and this morning 24.41V for SOC=99.3. These values are not consistent and I fear my settings are wrong though set as required (Ah at C20 for BMV). Or my bats are completely out of order.

When I manage to get there, probably April, I shall test my settings and SOC with electrolite density, but I may have to switch to LiFePo bats a little later.

Q2: Another idea: I tried to have some information about REDOX batteries which could store enough to regulate my power the whole year round (100kWh should do). No answer yet.

Q3: A third idea: I may have to change my panels so I look for wood looking things which could easily cover the whole roof, all spare place being filled with somme look alike materiel or wood. Any idea?

The last two questions are a bit far away from sea-faring devices, But our community is universal isn'tit?

More info as needed

Lionel

Lionel SEYDOUX asked
Lionel SEYDOUX answered ·

2 Answers

Smartshunt inaccurate SOC

Hi Guys, Thanks for the great community and support, I have always found this forum to be extremely helpful.

I seem to have an issue with the Smartshunt State of charge in a recent installation.


I have 8x 90AH 12v Yuasa batteries in parallel totalling 720AH.

I set the minimum discharge floor to 60% as my usage is minimal and I would be surprised if I reach that below 80%.


Now the Smartshunt indicate total consumed AH to be -48.1AH and the SOC to be 97%. I think this is inaccurate


Now if I do my math ( I could be ignoring many factors)

according to the set discharge floor of 60% I have 40% usable.

40% of 720AH = 288AH

Expected SOC = 100% -( 48.1/288)x100) = 83.2%

and not 97%

I am confused. can you please help :) below are screeshots and battery specs.


Many thanks



[image]

[image]

[image]

[image]

vanlifer007 asked
vanlifer007 answered ·

3 Answers

MPPT 100/30 Charge Control Battery Charge Display Issue

My battery state of charge display shows a charge drop when a load is draining the batteries..... but when voltage is being applied to the batteries it does show as charging up until I unplug the cord from the shunt and plug back in? Eg.....shows a drop of in charge but doesn’t show an increase in state of charge until the wire from the display to the shunt is unplugged and plugged back in. It has on a couple of occasions shown such a low state of charge that it shuts down the electrical even though the batteries were charged.

cdhackney asked

0 Answers

Smartshunt and Peukert coefficent?? Doubts...

Goodmorning everyone.

I bought victronenergy Smartshunt.

I must say that I am extremely satisfied with the accuracy of all the measurements.

Comparing the readings from TracerAn 3210 Epever and Smartshunt, they are surprisingly nearly identical, in both current and voltage.

They differ only by 0.02A and 0.02V. That is practically zero.


However, I am not convinced that the Peukert coefficient works.

In theory, by increasing the coefficient, the remaining runtime should shorten as the discharge current increases.

But it's the other way around:

for example, with a discharge current of 3 amperes, if I put coefficient 1.5 there is more time remaining, compared to coefficient 1.0.


The percentage of SOC also increases as the Peukert coefficient increases. I expected the opposite.


In my case, the statistics with default coefficient 1.25, seem too optimistic and less realistic than coefficient 1.0 or 1.1.

Can anyone clarify this for me?

francesco asked
francesco commented ·

3 Answers

Synchronize VE.Bus SOC with battery? Select on loss of communication source for genset

Synchronize VE.Bus SOC with battery

Has this item been rolled into dvcc? After some digging here it seems its been removed yet its still in the manual. The last mention of it in the changelog is in the v2.02 – 30 January 2017 Venus Os

Are you guys working on an update to the manual to remove redundant settings to avoid confusion?


loss of communication source for genset

I have a few systems I setup and support with auto start gensets, after a couple of weeks of bad weather one went into LVD during a sustained load at a low SOC. Voltage start timing settings were a bit too long to catch the voltage crash. LA batteries.

I had set start on loss of communication as a third fail safe to start the genset, and had the BMV as the source for genset SOC. However the genset didn't start as the BMV was still active yet the multi had shutdown. I had assumed that it would start on loss of comms to anything on the VE.bus. After rereading the manual, it's loss of communication to the SOC source.

Normally I disable the battery monitor in the multi to avoid the user accidentally changing the source.

I have now reenabled the monitor in the multi, which seems to be tracking the BMV and set the genset SOC source to the multi.

However Synchronize VE.Bus SOC with battery is completely missing so the only indication the SOC is being read by the BMV to the system is that its the same as the BMV.


Seems a rather complicated method, could we simply have this changed so we could select the loss of communication source?


This now raised another question, when performing remote configs through the portal the multi/quattro drops communications to the venus device for a moment. Will this cause a genset start?


alan asked
JohnC commented ·

1 Answer

State of Charge

We bought a used T@b400 with a victron 712 already installed. It does not seem that the state of charge is reading correctly. I shut off the battery and let it sit a few hours - the hand volt meter we are using says 14 volts which is similar to what the victron says for volts but the SOC is saying 27%.

The battery is a C235 so we did set the battery capacity at 235 instead of the default of 200 and we set the full charge V at 13.7

We are not able to see that any power is coming in to the batter either even on a sunny day- it does have the factory solar

We are a little lost with all the technical info on all this but it does not seem that the SOC Is correct or are we not testing that correctly? My husband is putting the volt meter on the leads going from the battery to the converter not directly on the battery - is that ok or should it be right on the battery like you read your car batter?


karent asked
karent commented ·

2 Answers

SOC DRIFT lithium with multi ii, mppt & cerbo

Hello,

I have tried seemingly everything but am obviously missing something.

I have a multiplus ii, cerbo gx and a 150/35 mppt.

The SOC drops by about 0.5V/hour until the alternator is connected.

I have followed all the lithium battery manufacturers suggestions and set the mppt voltage 0.03V above the multi voltage.

The system is going into float every dayand the current falls right off at that point so it's clear that the battery is charged.

There is 1 x 4000Wh lithium self managed battery and 6 x 400W solar so it's more than enough.

Can someone please assist

[image]

elysium asked

0 Answers

Optimise BMV SOC detection with ESS

I have a BMV712 connected to 4 x 220AH Victron Gel batteries in series, an MP2 3kVA and a 150/45 MPPT using ESS.

I put the bmv in when it became obvious that the MP2 was useless at accurately reporting SOC.

I have tuned the BMV as per docs and some guidance from victron (charge voltage midway between float and absorption, extended the time needed to sync to 8 minutes and reduced the tail current to 1.9%).

This works most of the time, the SOC gets to around 98% and then syncs.


Where it falls apart is if when there are bad PV days and the charge voltage is closer to float, the batteries don't sync. after a couple of days you end up with charged batteries but with a decreasing SOC reported.

When batteries discharge you now hit the ESS SOC limit too quickly (only use top 30%) which means the batteries never discharge far enough to hit bulk/absorption.

You're now get stuck in this float/discharge cycle, with battersafe increasing limits making it worse.

Being unable to force a remote sync means it is a real problem to break this cycle without having to start changing the ESS schedules and limits.


Is there a better way to setup the BMV?

For those doing partial discharge of batteries it isn't difficult to end up in this loop.


nickdb asked
alan answered ·

1 Answer

Bmv 712 readings out of whack

[image]

Hi guys, so I'm scratching my head at the moment for a few things that have been showing on my bmv-712.


1) tonight when I checked via Bluetooth on my battery, it was showing 63% soc, but 11.9V. It is a lead acid battery, 75ah, under bonnet. I double checked voltage, as 11.9V is 40%,not 63%. It was 11.9V. The only thing running is my fridge, and the car was taken out today for a run, which was about 30 mins drive total (2 x 15mins trips) yesterday it wasn't run, and fridge was off. I now have that battery on trickle charge to top it up.

2) when I'm driving I monitor the battery, and the most the bcdc1225d is putting in, even when low voltage is 5A. I've not seen anything above 5A. It goes from say 73% straight to 100%.

3) battery is a century 75ah deep cycle lead, prob 4 months old.


My questions are, should the bcdc be putting in more than 5a when discharged down to say 70%? How do I realign the bmv and battery soc?

System has been wired properly, only battery on battery side of shunt, everything else on load side. Has been running fine for a while, now just seems out of whack.


hairyhaggis asked
michelg edited ·

2 Answers

SOC no longer going below 40% in ESS

Hi,

since a few days,I recognized that my MPII (cerbo + 3xUS3000) does not discharge the battery below 40% even the battery was charged during the day to 100%.

I cannot remember that I changed any settings but I had installed the v2.62~4 and v2.62~5, but went back to 2.60.


Does anybody can help?


hansbaer asked
Izak (Victron Energy Staff) answered ·

1 Answer

bmv712 does not update SoC after manual Loading

Hi

loaded the battery manually.

SoC not updated?


What am I missing?


Thanks T

riker1 asked
riker1 commented ·

1 Answer