SmartShunt miscalculating Consumed Ah

Hi folks - I recently built a cabinet for a LiFePO4 house battery and Victron Orion-Tr Charger in the back of my truck, primarily to supply a Dometic 12v fridge. The setup works great, but the SmartShunt is miscalculating the amount of current used.

For example, yesterday, the SmartShunt went from 66% SOC to 100% SOC in three minutes. I anticipated it would, because the voltage was increasingly nearing the charger's specified Absorption voltage (14.4v) as I drove. The charger had already been on Absorption charge for nearly an hour of driving; and as I watched, it steadily increased voltage and decreased current, as it should. It was still reporting 66% SOC and -19.7Ah right before hitting the absorption voltage, and then it jumped to 100% SOC once the conditions for a full charge had been met (charge voltage, tail current, 3m wait).


I believe the discrepancy has more to do with discharge calculations than charge calculations: in another experiment, the SmartShunt showed a 0% SOC at 12.58v which should be somewhere in the neighborhood of 5% SOC for the LiFePO4 (and where I don't intend to take it regularly); but more to the point, it was showing that I had used 72.8Ah, from my 54Ah battery. So somehow the calculations are off in a way that reports more current loss than has actually occurred. I observe that the reported SOC is always lagging on each and every recharge cycle.

I'll post my settings below to see if there's something I can adjust to get accurate measurements.


- I don't believe the issue is with any of the full charge settings like Charged voltage, Tail current, or Charged detection time, because based on indicated voltage, full charge is being reported at the correct time.

- I don't know much about the Peukert exponent but perhaps it's something to look at. I've read here that the PE doesn't account for temperature, but I don't know how significant a factor that could be.

- Charge efficiency factor is set to 99% as a default for LiFePO4 batteries - we can adjust that if it could help.

- I don't know how the Current threshold is used, but this is the default, and we can adjust it.

- The Time-to-go averaging period is 3m by default; I changed that to 12m trying to even out the cycles of the fridge's compressor - when it's running versus when it's off - which report very different Time-to-go values.

- My battery is a Dakota Lithium 54Ah LiFePO4

Any help appreciated - I've read here on the Victron support forum that the defaults are only starting points and that massaging the variables is necessary in some cases - but this is off by such a significant amount.

itllgrowback asked
itllgrowback commented ·

6 Answers

ESS State of Charge


Hi, I have set up and very happy with an ESS system which comprises of MPPT solar charger and old solar edge inverter and Easysolar paralleled with a Multiplus on one phase. (Now I am happy with system but I will upgrade to three phase) BUT my question is this, I have a Loxone home automation system that monitors the Victron system and can fully control it via Modbus commands. What I would like to do using the information to my Loxone (ie tomorrows PV forecast) is to calculate using the PV forecast and the current SOC at 00:00 to decide how long I charge the batteries for (with some overage) or max SOC during my cheap electricity tariff so I dont waste any solar charge during the next day and I keep the batteries and at healthy level. I can not find the mod addresses that might do this with out creating my own complete charge routine in Loxone and going complete manual ESS on the Victron. So is there away of setting a modulus address for maximum charge during a schedule charge?

jonnyhottub asked
nickdb commented ·

3 Answers

Multiplus ii firmware update & configuration without batteries

I have a brand new Multiplus II 48/10000 and would like to update the firmware and configure before my 4 PylonTech batteries arrive. I have searched for and read a few Q & As on the subject.

The Victron videos indicate that this is possible using either AC in or 48v DC. I wanted to minimise risk and use a low value MCB for setup, connect up my laptop and USB interface and away we go. There seem to be differing views on whether the AC in only option will work

I have only AC in connected (100A cables) and earth from my adjacent consumer unit.

I initially connected it to a 16A Type B MCB and the MCB tripped after a few seconds whether in position I or II

I have read that there is an initial rush of current to charge internal smoothing capacitors, so I get that.

I repeated using a 50A MCB (not unreasonable given that a 100A MCB is recommended to match the Multiplus's 100A throughput capability) and this time the MCB and RCD (80A 30mA) both tripped after about 15 seconds.

Is my only choice to wait for the batteries to arrive ?

Is there something else I should try ?

Does it make a difference if I start up in charging only (position II) of inverter (position I) ?

Alternatively does this suggest there is a problem with the inverter ?

How many volts of DC would it require to fire up the DC side as I have a number of smallish LiPo batteries of different sizes that I could use ? I also have a 12v lead acid accumulator ?

Any help would be appreciated


carrpet asked

0 Answers

PYLONTECH US3000C or BYD LVL15.4 with QUATTRO 48/10000?

Hi everyone. We're looking to replace the flooded lead acid batteries on our existing system. We have a Victron Quattro 48/10000 two BlueSolar MPPT's, a BMV-712 and CCGX. The two VE.Can ports are available on the CCGX to connect the new battery so I don't think we need to upgrade to the Cerbo GX.

Our research has narrowed the options down to two choices. 5 x Pylontech US3000C or 1 x BYD LVL 15.4. I spoke to one installer that used to favour Pylontech and he recommended the BYD due to the amount of small issues he's had with the Pylontech installations, often needed to reboot. The final Canberra Battery Test Centre report strongly suggests the Pylontech will perform very well longterm and the BYD was poor.

I manage the system remotely most of the time and have someone onsite who can help. We depend on the system for uninterrupted power for our clients so reliability is key.

Is there anyone here who has experience with both batteries and the Quattro 48/10000? I'd really appreciate some guidance in order to make the right decision please.

Thanks for reading.


jeffc asked
yaute answered ·

2 Answers

Victron system in combination with dynamic pricing?

Hi all,

I'm new here and tried to search for the question above to no avail.

In the Netherlands it is possible to get a electricity contract based on dynamic pricing on an hourly basis (1 day forward). I'm thinking of a system where I charge a battery during very low pricing using net feed in and discharging during peak pricing (morning and evening).

Is it possible to set times where the battery will be charged with net feed in? For example 2pm if the battery is below let's say 80% SOC?

Is it possible to set timed activation where my home goes "off-grid" during peak electricity price (morning and evening) and switch this off at 10% SOC?

I've scanned the "Smartgrid II" manual for timed activation/deactivation but couldn't find something that resembled this fucntionality.

P.S.: what topic is this? offgrid doesn't seem to cover it?


EDIT: see as a data source for 1 day ahead "planning" of dynamic electricity pricing in NL.

jeepee asked
Christian Butterweck commented ·

5 Answers

Incorrect battery voltage reading on MPPT 150/45

The MPPT 150/45 charge controller is connected to a battery of 4 x 12V cells and is set to 48V. Although the multimeter indicates a Voltage of 55V across the battery, the MPPT is only indicating a Voltage of 18.89V across the battery. Does anybody have any advice?

johann-weinmann asked
johann-weinmann commented ·

0 Answers

Error on MultiPlus-II 48/5000/70-50 230V - error 11 step 6

Dear all,

i put into service a MultiPlus-II 48/5000/70-50 230V in october, using only the AC In coming from the grid and AC out 1 going to my home installation.

There are 3 US3000C and 3 US2000C batteries connected to it, along with a Cerbo GX. On the Cerbo I have an EM24 and a ET112 for the grid surveillance and photovoltaic production.

The Multiplus is programmed via MK3 on ESS assistant and french VFR2019 grid code as well as changes in voltage to fit the Pylontech batteries config.

Everything went allright until november, so about one month of service, when all of a sudden and without any changes in the installation and in the cables the Multiplus stopped working.

The error message is :

VE.Bus Error 11: Relay test fault on VE.Bus System
VE.Bus Error 11
BF safety test in progress - failing step 6

I spent two days checking everything, including going through all the points mentionned on the Victron site regarding the error 11.

No success. I contacted my vendor who sent the Multiplus to Victron as it was still under guarantee.

It came back the other day with a paper stating that the unit works fine and i have to pay for the error search.

However when I connect the Multiplus back in my installation, the error is still there.

I ended up connecting only the grid on AC In and nothing an AC Out 1 and 2, and also connected the batteries to + and -. The error is still there. The grid is at 240V and 50,1Hz, MK3 shows me everything in green.

Here are some tests done :

I switch on the unit with grid and without batteries
→ the unit is starting. It indicates Low battery which is normal.
I switch on the batteries
→ the unit goes in error (bulk and inverter on flashing, float stays on)

I switch on the unit with grid and without batteries
→ the unit is starting. It indicates Low battery which is normal.
I wait a coupe of minutes
→ lights for mains on and bulk go on, always low battery
I switch on the batteries
→ only the mains on is on
I disconnect the grid
→ the light for inverter on is on
I connect back the grid
→ the unit goes in error (bulk and inverter on flashing, float stays on)

I switch on the unit with grid and with batteries
→ the unit goes in error (bulk and inverter on flashing, float stays on)

I switch on the unit without grid and with batteries
→ light inverter on is on
I connect back the grid
→ the unit goes in error (bulk and inverter on flashing, float stays on)

Victron refuses to send me any checklist or test protocol, despite the fact that i paid for their „service“. So I don't know if they even tested the configuration that I used. When the unit came back it was reset to the default configuration, but that is not the way I need it to work, it needs to be in ESS and with VFR2019 grid code.

The vendor only says there has to be an issue in my installation, but everything else works fine. Also they do not give any information as where to look at exactly.

I was searching the forums including this one and there is absolutely no information what exactly step 6 is, the only thing i found is it may be a „communications error“. But what is supposed to communicate where and with what?

Also there is no explanation why it worked smoothly for one month and all of a sudden it does not anymore.

Any one have an idea what I should try next to find what the issue is? Any help yould be greatly appreciated.

rescue911 asked
nickdb commented ·

2 Answers

67 "BMS Connection Lost"

I have a MPPT 100/30, Multiplus 12/3000/120-50, Color Control Gx and a Li battery setup with a Ve.bus BMS.

When I set the 100/30 ->Networked Operations to controlled by BMS after about five minutes I get error #67 "BMS Connection lost" on the MPPT. I have updated all firmware/ software on all components in the system. reset both the multi and 100/30 back to factory settings and reprogrammed them yet the error still persists. Any ideas?

flip-flops asked
Paul answered ·

4 Answers

2nd Smart Shunt Disconnecting from Venus

I have a Raspberry Pi 3B running Venus running version v2.87

I also have 2 SmartShunts 500A/50mV on two separate USB ports. One is to monitor the coach batteries and one is to monitor the chassis battery. Both have been reporting fine but sometimes the coach battery or Chassis battery drops off the VE network. When I'm at the RV I'm able to connect via bluetooth and reset the connection but now the RV is in storage for a couple of weeks and the the coach batteries are loosing the connection. Eventually I will be adding solar to the RV. I really appreciate this ability! I will also be adding an additional Pi running Home Assistant and looking to get the data using the modbus interface.

I just updated to Venus 2.89 and was wondering if this may have been addressed.

sungunner asked
sungunner answered ·

3 Answers

SoC why is it so flaky?

I have two installations both ESS grid-parallel battery systems both primarily time-shifting off-peak electricity to peak times. Each using multiplus II 48/5000/70 units.

2p16S configuration brand new EVE 230Ah LiFePO4 cells with Daly BMS 250 amp.

However, despite the nameplate capacity being 48V 460Ah for each pack, the actual performance varies considerably with temperature for example. As such I might get 300Ah before the SoC shows as low (I am using 25% SoC as ESS low limit) or I might get 350Ah.

I understand that voltage, on paper, is a more accurate measure of charge, than counting charge in and out (Ah) but under load, it is unreliable as it drops. So we use SoC whilst under load. However, it doesn't seem to be very intuitive or clever.

How is the battery pack in my MG5 LR EV managing itself without what I am having to do - the constant tweaking of the capacity in VEconfigure or the ESS stop on SoC level.

I want to set the thing up and then forget about it.

Also, can someone explain what the adaptive charging in veconfigure is all about?

djdemond asked
djdemond commented ·

2 Answers

Multiplus II ignores absorb settings and keeps overcharging my LiFePO4 batteries

Hi everybody.

We have a Multiplus II 5000/48 combined with a 52V 160Ah LiFePO4 battery controlled by a Batrium Core1 BMS communicating over CAN to the VE.CAN bus.

After I removed 10pcs Enphase IQ7+ from the garden house roof, I connected the 10 pcs AEG 365Wp panels in a 5s2p config to the SmartSolar 250/100.

ESS agent is running with absorbtion voltage at 53,6V and float on 52V

Whatever, however and whenever I do, the Multiplus - even with a de-activated charger - KEEPS pushing my batteries over their limits like blixen and thunder pulling the sleigh without Santa Clause controlling them.

I know bulk throws 56,8V at my batteries (somewhere between 55,5 and 56,5) but this SHOULD change into absorbtion when the batteries have reached at 53,6 Volt.

I disabled DVCC, although the CANbus from my Batrium BMS nicely shares Voltage, current and temperature to the portal.

I am kind of getting frustrated and at the moment very reluctant of expanding the MultiplusII with two brothers and some pylontech batteries......

Any help would really be appriciated!

Paul asked
Paul answered ·

2 Answers

VRM Instance Number Changed


Amongst a couple of firmware upgrades and factory resets to my Cerbo GX, two devices have changed VRM instance. E.g. Smart Solar MPPT changed from 278 to 279. This also affected a GX Tank 140 input.

Is there an explanation for this, and is there a way to move VRM history from 278 to 279? I do not want to lose the history for the original VRM instance device.



stevomyatt asked
Joe answered ·

5 Answers

Multiplus UK G98 G99 non-compliance update

Dear Victron,

It seems very likely, from the email below (names and some details omitted) that the docs you submitted to ENA in early October will not be sufficient to gain compliance "due to important information being either incorrect or missing altogether".

Please could you provide some kind of timescale for when you will be able to provide updated documents? I note that NGED are, helpfully, willing to liaise with you in order to speed up the process.

Providing a response on this forum would, I'm sure, be very welcome by customers like myself.



Good afternoon,

I have been asked to contact you, to explain the current compliance status, with regard to ENA EREC G99/1-9, for the Victron Multiplus II 48/5000/70-50 and Victron Multiplus II 48/5000/70-50 GX (which share a common compliance report).

As you may already be aware, as of 1st September 2022, any device that is recognised as an Energy Storage System (ESS) had to meet the full technical requirements of ENA EREC G99/1-8 (and subsequent revisions), where they were previously exempt from some of the newer requirements, that were introduced by the European Network Code: Requirements for Generators (RfG). This requirement was communicated well prior to September 2022, and was published in EREC G98/1-5 and EREC G99/1-7 in August 2021.
Many manufacturers pre-empted this change, and made their ESS compliant before need. Others waited until the deadline to submit renewed compliance documentation.
Where an ESS device had not met the requirements on 1st September 2022, it was marked as ‘non-compliant for new installations’, by WSP, in the ENA’s Type Test Register, and manufacturers were pushed to renew their compliance documentation.

The ENA, WSP and DNOs have the authority to determine Generating Unit compliance under (to name just one document, to avoid confusion) ENA EREC G99, which is an Annex 1 document of The Distribution Code of Great Britain (DCode).
DNOs have a statutory obligation (and licence condition) to abide by the DCode and (in particular) its Annex 1 documents.

As the Victron Multiplus II 48/5000/70-50 (ENA Type Test Register reference: VICEN/02689/V2) Energy Storage Device’s current status is ‘awaiting assessment’, in the ENA’s Type Test Register, I have conducted an in-house assessment, in order to provide our customers with a response sooner than we would be able to if we were to wait for WSP’s assessment. My assessment is based directly upon the requirements within EREC G99/1-9 alongside prior assessments by WSP (what they will be looking for), and my own experience.

I have assessed the Victron Multiplus II 48/5000/70-50 and Victron Multiplus II 48/5000/70-50 GX as being ‘non-compliant’ with ENA EREC G99/1-9, as things currently stand, due to a number of shortfalls in the compliance form. As Victron have made their form publicly accessible, via the ENA’s Type Test Register (i.e. it’s not a restricted document), I believe that I can elaborate upon this:

Advisory and failure points:

[information which could be considered commercially sensitive omitted]

Hopefully, you will be able to see that this compliance status has not come about due to minor inaccuracies, which could be forgiven, but due to important information being either incorrect or missing altogether.

As a consequence of these findings, National Grid cannot accept the connection of the Victron Multiplus II 48/5000/70-50 or Multiplus II 48/5000/70-50 GX, in parallel with our Distribution Networks, until such a time that Victron have provided alternative or additional information that demonstrates compliance with the latest version of ENA EREC G99.

I am comfortable with you informing Victron of the above, either directly or indirectly (through your equipment supplier), so that they may complete and provide alternative or additional evidence of compliance. They should do so primarily to the ENA, but National Grid Electricity Distribution would also be willing to take an early look at any documentation, should Victron see this as desirable.

I am confident that, given time to complete the documents accurately, Victron will be able to make these devices compliant (perhaps with another firmware update) but, unfortunately, we will have to wait until they have demonstrated this before we may accept these on our networks.

Kind regards,

Engineering Policy

johnone asked
strix commented ·

18 Answers

Orion Smart 12/12 30A non-iso: basic help for novice



I am very new to this. I've had a renogy lithium leisure battery fitted and the orion charger into my 2015 Peugeot Boxer, however the mesure battery just barely seems to be charging. There is 14+ volts coming to the charger when the engine is on, but the output maxes out at 12v, and the retained power in the battery is barely enough for an evening if very light use (an led light, occasionally the pump for the tap, that's it!), and not enough to run the diesel heater for more than ten minutes. I think I may just have some settings wrong but I've no idea what I'm doing - I've literally only downloaded the app today and done a but if research but got no further. Most obvious thing seems to be switching the setting to charger from power supply - is this right? And are any other settings incorrect? Please help, I'm in France and it's freezing! See pics.

Thank you thank you!


tomba12345 asked
tomba12345 answered ·

2 Answers

Pylontech Force L1 and MP2, will not be displayed. Help


Image CaptionHi.

I have a problem I have a Multiplus 2 GX and a Pylontech Force L1 7.1 kWh.

Connected the Pylontech with the original Victron Type A cable. On the MP2 on the VE.Can port and on the Pylontech on the Can port. Set 500kbit/s. Unfortunately, it only shows me the Pylontech battery, but not a single value. see photos. Firmware is up to date.

need your help don't know anymore.

Greetings Marcel



Habe ein Problem.

habe ein Multiplus 2 GX und ein Pylontech Force L1 7,1 kWh. Habe die Pylontech mit dem Original Victron Typ A Kabel angeschlossen. Richtig rum natürlich. Am MP2 am VE.Can Port und am Pylontech am Can Port. Habe auf 500kbit/s natürlich auch gestellt. Leider zeigt er mir nur die Pylontech Batterie an, aber kein einzigen Wert. siehe Fotos. Firmware ist aktuell. Brauche eure Hilfe. weiß nicht mehr weiter.

Gruß Marcel




mwitzig2000 asked
mwitzig2000 edited ·

0 Answers

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