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MultiPlus Compact 12/1600/70-16 doens't charge to 100% goes into decharging float

I have 2 Victron AGM Supercycle 170 batteries in parallel and my Multiplus doesn't seem to charge them to 100% but comes in a float stage, slowly discharging.

I restarted the Multiplus. It goes into bulk for about 30 seconds, then to absorbtion for 15 minutes with only 1,8A of charging and then to float with 0,3A

As this system has some small users while idle, it actually is decharging slowly.

I would expect that when the BVM712 is at 84% the Multiplus would go into bulk and then absorbtion until almost full and the to float where the float charge is equal or higher than drain from small users.

The system looks like this;

  • MultiPlus Compact 12/1600/70-16 running firmware 497
  • Color control GX running firmware 2.89
  • BMV712-F running firmware 4.08
  • 3x SmartSolar Charger MPPT 75/15 running firmware 1.59
  • 2x Victron AGM supercycle 170 in parallel
  • Victron Cyrix which charges the starter battery

The multiplus, BMV and smart solars are all connected to the color control using the VE bus.
The smart solars and BMV 712 also are connected in their bluetooth network
Interesting enough the smart solar shows in their configuration (in the color control) that they are not networked.

lsi asked
JohnC commented ·

2 Answers

Victron Lifepo4 never goes to float. Is this a problem?

My system is all Victeon. CerboGX, Victron Smart LiFePO4 200Ah, Multiplus, Lynx Smart BMS MPPTs etc and everything is controlled by DVCC so as far as I’m aware it should be self managing, but it just sits in Absorbtion from the Multiplus output once the battery is full.

Is this fine?

I’m worried that it will damage the battery to be constantly in Absorbtion for months on end.

sweyn asked
Stefanie commented ·

1 Answer

Muiltplus 3000 goes into float and not Bulk mode

My Muiltplus 3000 goes into float and not Bulk mode and the lithium batteries are 84% and 76% and thats with shore power so it look like it a trickle change right now ???

Can someone recommend a company to log in and look at my settings..


Robert Somerville asked
jsallee edited ·

1 Answer

Why does my Multiplus not ever indicate float?

My Victron Multiplus doesn’t ever appear to reach float state and continues to indicate absorption continuously. I’ve heard that float is disabled for lithium batteries, so maybe seeing absorption indicated is normal? I have Victron smart lithium batteries (4 X 200AH in parallel). I have the multiplus configured for lithium, fixed charge curve, 14.2 V absorption, 13.5 float, 2 hours absorption time and 7 day absorption interval, 14.0 charged voltage. The system includes a Lynx BMS, Cerbo and 3 Lynx distributors.

jimgeier asked
Stefanie commented ·

1 Answer

Float voltage different from setting

Hi there.

I have 3 x SmartSolar MPPTs connected to a bank of Lead Acid batteries with a SmartShunt, Multiplus and a Pi running Venus OS. The Multiplus is off and the MPPTs are using VE Smart Network to sync.

Even though the float setting on all MPPTs is 13.6V, the float voltage on the battery bank is being held at 13.2V. This is even if I take all loads off of the batteries. Can anyone explain why there is this difference?

Many thanks.

lawrence-craig asked
seb71 commented ·

6 Answers

MPPT 100/30 float issue

Hi all,

I've had a look through the masses of previous questions and unfortunately couldn't find any that were quite the same as mine.

Recently I have noticed that my SmartSolar 100/30 completes it's bulk and absorption stages and enters float mode. When in float it will match any current draw from the battery for roughly an hour and then will suddenly no longer keep matching the battery and it will then start dropping down from 100%.
It says it is in float mode, there is plenty of sunlight and panel voltage present, however it doesn't output any charge to the battery. No other chargers connected to the battery.

I have the float voltage set to 15.8V and even when the loads connected to the battery increases it does not kick it back into bulk.

I then have to reset the controller by disconnecting the solar, then battery and reconnecting, which it will then it go back into bulk mode, absorption mode and then eventually into float again.

Has anyone else experienced this issue? Is it potentially a firmware issue?

Thanks

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ksmith asked
jcallin1 answered ·

10 Answers

Correct sizing of solar panel for float charging

I am going to add a solar panel to my boat just for providing float charge to my starter battery (12v 240ah) and bow thruster battery (24v 240ah). I will use a Smartsolar 75/15 controller and an Orion 12/24 to step up to the 24v battery.

My question is this: what current do I need the panel to provide to enable float charging of these batteries? I'm think a 115w panel will provide typically 8 amps in the sun but rather less most of the day and, of course, nothing at night.

Not worried about bulk charging - the alternator will do that and these batteries will only discharge at start or when the alternator is running

thanks

Rob

rob-dean asked
kevgermany answered ·

2 Answers

Battery in floating even if the load higher then the solar power

Dear All,

Can someone have an idea why the Multiplus II stay in float mode even if the required power for the load is higher then the solar power. Normally, battery power must be combined with solar power to absorb the load power.

Best regards

nostromo asked
nostromo commented ·

2 Answers

Charger says "Float" even though it's below Float voltage.
I really feel like I should be understanding this better than I am. I already read a bunch of posts here. I understand how "Absorption/Float/Bulk" works in the sense of charging from zero to 100. But I'm confused about it right now, as it discharges and then charges up again from 65%.

I'm doing an initial slow cycling of my batteries to get them ready. And I'm a little confused by what I'm seeing here. Currently sitting at ~53.5 volts, below the float voltage, and it's charging my battery at my specified rate. Why does it still say float? There's something about Float/Absorption/Bulk that I'm not getting. Wouldn't this be a bulk phase since the voltage is lower?


Mostly, I'm just confused why it says "float" when it's charging at the bulk charge rate.

Specs:

  • Victron Multiplus
  • Absorption Voltage: 56.8v
  • Float Voltage: 54.0v
  • Battery: LiFePO4
    • 300AH
    • 48v


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EDIT:
The voltage was previously down to 52.15v, and still said "float". That doesnt seem right.

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coreyzev asked
goncalo answered ·

3 Answers

Multiplus 2 with ESS Assistant shows strange Float charge behaviour...

I use the following setup: ESS System with a Multiplus II 48V, CerboGX and a Lithium NMC battery that is protected by a built in BMS. The Multiplus does not communicate with the battery. Charging and discharging is controled by voltage.


I am currently testing the following settings:


TAB: General

System frequency 50Hz

Shore current 13.0 A

Overruled by remote unchecked

Dynamic current limiter unchecked

External current sensor connected (see manual) unchecked

State of charge when Bulk finished 100.0 %

Battery capacity 50 Ah

Charge efficiency 0.95

TAB: Grid

Country / grid code standard Germany: VDE-AR-N 4105:2018-11, internal NS protection

LOM detection AC input 1 Type B (grid code compliant)

rise-in-voltage protection U> 253.0 V

start network service HF treshold 50.20 Hz

P(f>) droop 5.00 %

Use Aux1 as disable FeedIn signal checked

Maximum AC current for charge or feed in 100.0 %

Reactive power regulation Use a fixed Cos Phi

Filter time for reactive power 3.3 s

Cos phi at point 1 1.00

TAB: Inverter

PowerAssist unchecked

Inverter output voltage 230 V

Inverter DC shut-down voltage 39.20 V

Inverter DC restart voltage 45.60 V

Low DC alarm level 45.60 V

Do not restart after short-circuit (VDE 2510-2 safety) unchecked

enable AES unchecked

TAB: Charger

Enable charger checked

Weak AC input unchecked

Stop after excessive bulk unchecked

Lithium batteries checked

Configured for VE.Bus BMS unchecked

Charge curve Fixed

Absorption voltage 53.00 V

Float voltage 52.98 V

Charge current 35 A

Repeated absorption time 0.25 Hr

Repeated absorption interval 45.00 Days

Absorption time 1 Hr

TAB: Virtual switch

TAB: Usage

Virtual switch usage Do not use VS

TAB: Assistants

TAB: Assistant Configuration

ESS (Energy Storage System) (size:962)

*) System uses LiFePo4 with other type BMS

(This can be either a BMS connected via CAN bus or a BMS system in which the

batteries are protected from high/low cell voltages by external equipment.)

*) The battery capacity of the system is 50 Ah.

*) Sustain voltage 44.80 V.

*) Cut off voltage for a discharge current of:

0.005 C= 47.80 V

0.25 C= 47.20 V

0.7 C= 46.60 V

2 C= 46.10 V

*) Inverting is allowed again when voltage rises 1.20 V above cut-off(0).

*) Relevant VEConfigure settings:

- Battery capacity 50 Ah.

- PowerAssist unchecked

- Lithium batteries checked

- Dynamic current limiter unchecked

- Storage mode unchecked



Total size of all assistants including the required

(hidden) system assistants is: 1021





It works pretty well...


Now my question:

When there is enough solar to power home consumption the rest is used to recharge the battery. In bulk charge it all works fine, as soon as the absorption phase ends, the inverter discharges a little bit to reach the float voltage of 52.98 V. But then the inverter stays on (green light is on) all the time.... even though there is enough solar power to power the house and therefore the inverter not needed.


How do I have to change the settings in order to prevent this behaviour?

Or is there a way to completely disable float charge, as it is not useful for my type of Lithium-Ion battery?


Thanks in advance for your feedback and help!


save1power asked
Alexandra edited ·

2 Answers

Pylontech : pas de tirage et multiplus : no float

Bonjour,

J'ai multiplus 3000kva/48, avec 4 pylontech us2000C en ESS.

Pourquoi j'arrive pas à utiliser l'énergie des batteries ?

En paramétrage, j'ai utilisé :

https://www.sines.fr/compatibilite_vicron_pylontech.html

Qui est identique en paramétrage victron mais synthétisé.

Et le multiplus ne passe jamais en float. J'ai un retour de batterie en : "ralentir la charge".


J'espère avoir donné toutes les informations.

Merci de votre aide.

vins asked
vins answered ·

4 Answers

MultiPlus-II 12/3000/120-50 120/240V SOC when in float
I recently completed installation on my Victron MultiPlus-II 12/3000/120-50 120/240V Charger/Inverter along with a SmartShunt 500A and 300AH of 12 LiPO batteries and Cerbo GX in my RV. I have not gotten a chance to install the PV system yet. Everything works great, but I am trying to tweak my settings. What I am noticing is that when I am in Bulk and Absorption, my batteries charge to 100% SOC. Once it goes to float, the parasitic drain of the 12v system (approx 23w) slowly drains the battery SOC down.. I haven't see how low, but I was wondering is this normal? Shouldn't the charger keep the battery at near 100%? Is it possible I didn't correctly configure my SOC correctly on the shunt? If so what is the typical conditions to zero out the SOC? Is this maybe how the system protects the longevity of the batteries? Sorry for the rookie questions, just in all my research I haven't seen anything about this. I just want my system to be charged to 100% when in use so that if we lose or need power I'm not starting at 80% SOC. Any suggestion would be appreciated.

Absorption Set at 14.2v

Float set to 13.6v

Smart shunt set to 14.1V

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paul-martin asked
paul-martin answered ·

2 Answers

Absorption to Float triggered at 40% or 60% of SoC (Multi + BMS + VE Smart Lithium LiFePo4 300ah Battery)

Multiplus is going from ABSORPTION to FLOAT charging state when the SoC is at 40% o 60%, which should actually been triggered when the battery is fully charge, if I'm not wrong.

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Multiplus settings are the recommended ones for Lithium batteries. So floating is at 13.5v and absorption is at 14.2v.

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- Could it be the Absorption time?


Any help would be really appreciate!!! thanks in advance to this great community.

esteban-moreno asked
klim8skeptic edited ·

1 Answer

Multiplus float voltage not stable causing battery in charging/discharging cycle

I have Multiplus 3000 and two battle born Lithium batteries in parallel. The trailer is plugged into my house’s 30amp. The float voltage is set to 13.5v. The Smart Shunt is connected to the batteries terminals and the Smart Dongle is plugged into the buses. When Multiplus is in float mode and DC load is running, I noticed sometimes the power was pulled from the batteries and sometimes the Multiplus charged the batteries. The voltage is bouncing up and down. I set the Multiplus to charger only, it’s the same. Is it normal the batteries got charged/discharged cycle in float mode and the voltage bounces? Should I disconnect the battery when plugged in to avoid cycling the battery?

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joelimvp asked
joelimvp answered ·

2 Answers

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