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Multipluss-II with eTower Batteries stats not updating


I have the following setup:

MultiPlus-II 48/5000/70-48
Color Control GX
Etower freedom won x2 modules (200ah)
SmartSolar MPPT VE.Can 250/100 rev2 with 12 panels on the roof


Everything works as far as I can see, except that the VRM does not update the battery V,A or watts correctly, the SOC and battery % updates in realtime.

If I redetect the battery, the stats will refresh correctly, but they never move from the last values.

The battery is connected via the CAN cable provided by the freedom Won installation.

I have access to the VRM of an identical site and the stats does update in realtime, the only difference I can see in settings is a CCGX firmware version difference where the working one as an older firmware (v2.73) and mine using v2.89.

Any ideas why ?

charl-de-bruyn asked
charl-de-bruyn commented ·

1 Answer

MPPT Charging Voltages in Networked Mode Set with bluetooth or remotely?

I have 4 MPPTs, 3 Multiplus 2 a BMV 712 and a Cerbo gx, all networked.

In order to change the battery charging voltages, is there a centralized was of doing that where the values are set in one location and those values are propagated to all the devices?

So far, I have been using the VRM Configurator to set the voltages on each of the Multiplusses and the bluetooth to set them on each of the MPPTs

Salim Naufal asked
wkirby answered ·

1 Answer

Charging - Bulk, Absorption and Float

Hi All

Can someone help validate / correct my understanding on the above.

I am trying to understand in simple terms what is happening in these states of charge. I have read Energy Unlimited - and other documents - I think I've got my head around it - but fear I haven't understood it correctly. Be gentle with me if I am being stupid :-).

Bulk -

The charger throws amps in to the battery - as many as it can (while being limited by any specific limits set in the charger). As loads of amps pile in to the battery - the battery voltage rises. When the battery voltage reaches the specified absorption V - bulk stops - and absorption starts. This phase will simply go on as long as it takes - to get to the battery V to the set absorption V. This could take 1 minute, 1 hours, 3 hours....

Absorption -

The charger continues to throw amps at the battery - but in this phase it doesn't allow the voltage to go above the specified absorption V. So, as time goes on, in this phase, the number of Amps drop off, as the battery gets fuller, the charger requires less amps to maintain the battery at the specified V. Eventually the number of Amps being thrown at the battery drops to almost nothing - to hold the battery at the specified absorption V. At this stage, or, when hitting the time limit set for absorption, the charge stops absorption and switches to float. This phase will go on for as long as it takes, or, for a specified time if time limited in settings of any given charger.

Float -

The charger now just holds the battery at a lower specified voltage - trickling the lowest number of Amps in to the battery that it can- to maintain the float Voltage.

Feedback please - am I way off the mark ?



miya asked
klim8skeptic commented ·

2 Answers

Multiplus-II with GoodWe Inverter and DIY Battery

Hi all,

Looking to get some feedback on the design below. Looking to incorporate a DIY battery solution at home with my current PV inverter (GoodWe 10KW). Looking to use the Victron MultiPlus-II 10000 for the 1:1 ratio but wanted to understand if it'll work well with the GoodWe Inverter and the JBD BMS. Are there any suggestions/change you'd recommend?


Thanks for your time!

Some other tidbits that might help:

  • I'm based in Australia.
  • GoodWe inverter and panels are installed.
  • I have the LiFePO4 cells on their way.
  • Would want solar to supply loads first and then the remainder to charge the battery

kenneth-lam asked
Rob Duthie edited ·

2 Answers

RV Inverter Upgrade: 12v vs 24 Inverter

RV Upgrade; The coach has on onboard 4kw generator that will be used to charge the batteries in addition to the 950w solar panel array.

I am going to be running 4x 12.8v 200ah lithium batteries and deciding whether to run as 24v paired with a 24/5000 Quattro or run as 12v paired with 12/3000 Multiplus.

If I go the 24/5000 route I am having the panel upgraded from 30amp to 50amp. The quatrro has a much beefier charger in it and will almost cut charging time in half compared to the Multi-plus so I am leaning that direction.

Other than faster charging and additional power headroom, what else am I not considering as potential downsides or upsides to the 24/5000 setup vs the 12/3000 setup?

duffer41 asked
Kevin Windrem answered ·

3 Answers

Standby Battery Charger

We have small installation comprising 5*200W panels, MPPT 100/50, Cerbo GX and 4*110Ah batteries, running a remote amateur radio repeater station and emergency radio communications for RAYNET.

We are considering installing a mains battery charger (We still have mains on site), controlled by the generator relay option on the GX to switch the charger on at a low battery voltage.

My question is, can we connect the battery charger directly across the battery through a suitable high current diode, with the same in the feed to the battery from the MPPT 100/50.

Thanks in advance. (Colin)

newtor asked
wkirby answered ·

2 Answers

Blue Smart IP65 24/8 charging 2 battery banks possible?

I have a boat that has two 24V banks (starter/house), and a 1-both-2 manual switch - it seems that previously an old changer was connect on the house side.

I plan to change the type of house bank to AGM/Gel so also ending up with two different types of banks.

I wanted to do the same with the new charger - but would not expect it to work as intended unless I have a Cytrix ct to combine those.

Is that a correct assumption - or is the battery combiner unneeded?

Would a 2 (or 3) output charger had been a better choice?

stevenew asked
stevenew edited ·

0 Answers

disabling battery charge from PV

Hi, I would like to charge batteries only from grid when second tariff. How to disable charging from PV, despite activated charging scheduler, PV have priority. :(

Thank you in advance for help

robertpe asked

0 Answers

SmartSolar MPPT 150/85 VE.Can - No current flow in Bulk with PV at VOC

I have a SmartSolar MPPT 150/85 VE.Can connected to 6 320W Renogy solar panels wired in 2 parallel series of 3 panels on an RV. I have 15A fuses on each string and a 25A circuit breaker in between the fuses and the MPPT charger. The new system has worked fine for weeks, until one morning after a day of the charger being in float mode for most of the day, both 15A fuses were blown, but the 25A breaker was not tripped. I also noticed that the charger said that the PV Array voltage was within a volt of the battery bank when the array was actually at 0V and/or completely disconnected.


After replacing the fuses, the charger seemed to work for the rest of the day. By the next day, one of the 15A fuses was blown. Part way through the following day, the charger stopped charging altogether even though no fuses were blown or circuit breakers tripped.


Now, when the charger is in bulk mode during the day, it reports the battery voltage and PV array voltage but no (<5W) of actual charging, At night, it still reports a PV array voltage of approximately the battery bank voltage.


warren-b asked
stewarthanford77 answered ·

7 Answers

IPzS battery monitoring

So I now have everything up and running except for one more building (the main one) to connect to my off grid setup.
But I am not sure I have everything set up right on the battery monitoring.
I have a 930ah (C5 rating) IPzS 48v battery setup,
Victron multiplus 2 48/8000/110 inverter
fronius AC 8.2-1 inverter on AC1 out
Smartshunt 500
Cerbo GX

Yesterday it went to absorption at 99%, but this morning it went in to bulk charge at 96%, is this to be expected or too early, it went to absorption again at 99% today
Just wondering if maybe I have something setup wrong in VRM settings
I have Multi set with battery monitor on, 85% when bulk finished, battery capacity 1140ah (C10 rating) and charge efficiency 0.80% and the same in the shunt, if I set the battery monitor in VRM to either the shunt or the Multi the result is pretty much the same.
Using the flooded tubular plate curve.
It does appear that there is a lot more amps going in compared to going out.
Any advice greatly appreciated here.

scraggs asked
scraggs commented ·

1 Answer

Charging lithium to 100% SOC

In my Airstream travel trailer I have two 300ah 12v Victron Smart Lithium batteries in parallel, BMV 712, 800w of solar, Victron 150/70 MPPT controller and MultiPlus for shore power / genset power for charging.... and CCGX for system coordination.

I also own a Telsa, and the best practice, generally speaking, is to run the lithium pack between 30% and 70% SOC to maximize longevity. We only ever charge to 100% ever 2-3 months when needed for extended use. It has active cell balancing, of course.

The Victron batteries have passive cell balancing, which of course means you must charge and float at 100% SOC to balance the cells.

My question is - does charging the Victron 12v Lithium batteries to 100%, over and over again (on a daily basis) degrade the performance of the Victron lithium cells at an accelerated rate? Or... should I manage the batteries like I do the Tesla cells - between say 30 and 70% SOC, and only fully charge / balance on, say, a monthly basis?

In other words, what are the best practices for yielding the longest lifespan / longevity from Victron 12v Lithium batteries aside from caring for them with low charge / discharge currents?

Thank you Victron community :)

wulfraat asked
friaras answered ·

3 Answers

Battery voltage not increasing/stuck while charging bulk

I'm installing a new system for a van build. Trying to do a full charge of the battery, but it seems the charging gets "stuck" (battery voltage varies ~0.1 up and down) after ~5 minutes or so. The charger stays in bulk mode. I've turned it on and off a couple of times and changed some settings, without any success.

Things I'm trying to understand:

  • First of all, what can be wrong?
  • Additionally:
    • How can there be a high charge current, but a battery that isn't charging? Is it bad for the battery or charger to leave this on?
    • Is this decrease in cell voltage normal?
    • Does the setting "charged voltage" in the smartshunt have any effect on the charging process, and is 13.2 correct for a lithium battery?

What happened

Initially, the battery was 13.1v. Did a charge with the standard lithium setting. The battery got to 13.42, and stopped charging. Then went to inverter mode. The next day turned the system back on, and it went to charging in bulk again. First started noticing cell voltages didn't increase. Additionally, the battery voltage seemed too low (should go up to 14.2 right?), so I started tweaking the settings and turning the system off and on in the hope to solve it.

What I'm noticing each time:

  1. Before turning it back on, the cell voltage has dropped back to ~3,34 (there are no loads connected to the system)
  2. I turn the system on, first minutes seem well, voltage is steadily increasing, the charger doesn't make a lot of noise yet, status is bulk mode
  3. After ~5 minutes the charger starts making more noise, and the battery voltage goes ~0.02 beyond the last highest voltage and then stays there.
  4. After ~20-30 minutes, battery voltage seem the be fluctuating 0.01 increase/decrease in battery cells, still bulk charging
  5. I check the charge current and voltage through the smartshunt. Voltage is 0.5 higher than battery, charge current at max 35a. The battery temp is normal (around 30 degrees Celcius)

Here are some screenshots from the battery status during one of the tests:


Components currently installed:

  • Victron Smart Litium battery 330 Ah, updated to last firmware
  • Victron SmartShunt, updated to last firmware
  • Victron Multiplus 800/12/35, updated to last firmware
  • Victron VE.bus bms
  • Victron Gerbo GX

Some system images (wiring diagram at the end of page):

















Wiring diagram


daniel-swaab asked
Stefanie answered ·

1 Answer

Selecting a charger and inverter for a 100V/50Ah/5kWh LiFePo4 battery

A 5kWh 96V LiFePo4 battery fell into my lap, a it's a SonnenModul4. Ever since I've been studying up on solar systems, as I plan to go to Africa, to live and work from a solar powered camper, exclusively, for the next 5 years. I never thought I'd be able to put in such a powerful and reliable battery. This feels revolutionary.

I presume a solar system built around such a battery looks like this:

  1. a single string of 3 or 4 solar panels of around 40V each, each with 375W. They have to fit a 170x400cm roof area. During most of the day that should give me 750W or 1000W, ample.
  2. a MPPT charger with overcharging protection to connect the PV to the battery. It should be able to comfortably work with 160V DC in
  3. an inverter, to give me 230V from the battery voltage. at least 2kW allows me to cook without switching of appliances like the fridge. I could even run a basic air conditioning.

I suppose this battery has a BMS to re-balance the cells, but I don't know about any protections like overcharge or over-current (short-circuit). My questions:

  1. is the system complete? would I need anything else?
  2. what protections should I take care of?
  3. what devices would be recommended?
  4. maybe there is an inverter with an integrated MPP tracker?
  5. is there a way to run the inverter directly of the solar panels, switching to the battery only when needed?
  6. bonus: how to keep the solar panels cool (as they'll get very hot)?

Though I work with electronics, I'm still a newbie when it comes to best practices, the market and how to layout a system. Any advice would likely be taken ;-)

chromebin asked
nickdb commented ·

2 Answers

What 3P inverter


I own 24 (310wp) solar panels split over 3 phases on Enphase. So... no DC. Grid tied 230V AC only.

Now i would like to attach a 10-15 kw LiFoPo4 Home battery.

Could i use one inverter to combine the 3 phases to charge one battery? Or do i have to buy 3 inverters (one for each phase) and 3 batterys?

I would like to run my home appliances by solar power.

The "house" has 2 heavy loads. One 3P (6kw max) heatpump and an EV charger. (22kw reduced to 8kw so i can mostly charge within the solar curve.)

Could someone please tell me what inverter would be suitable?

I just would like to figure out the costs.

If i need to triple everything....


Very expensive!


macmaniac78 asked
Mike Dorsett answered ·

1 Answer

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