accuracy Image


why is current going/come to/from nowwhere in dashboard

I always had inaccuracy in my systems between the current the REC-BMS shunt shows and the Multiplus2 DC current, although inbetween there are no loads or other systems. So i bought i victron smart shunt to check it in more detail. Now the shunt shows that the battery delivers 47Amps, but the Multiplus means, that 48,4A arrives. If you switch on in VRM the DC Loads, than it shows the missing 1,4Amps coming/going from/to anywhere which does not exist. So what is here wrong??

The battery delivers 47A, a not existing DC generator delivers 1,8A and the DC current sense of the Multi measures the 48,8A althoug only 47A exist.

I always see those differences between BMS current and MP current and it looks like it could be a source of relevant inaccuracies?

Can someone explain this? This is just a test system without grid meter installed. Values from "grid" are the AC-Out measurement from the MP2.


gnagflow asked
Matthias Lange - DE answered ·

2 Answers

Lets try a second time. Whats the Voltage accuracy of Victron products?


It seems questions often arise on this forum about the Voltage accuracy of Victron units and variances between voltages measured vs what's displayed on the app.

SINCE there is zero information about the accuracy of the Voltage meters in Victron products, it makes sense that some questions be answered on this community page, which is there to help Victron users!

Elvis, Kevgermany - You didn't like my replies to you and those who commented on my previous question, before you got offended and blocked my account - Maybe go back and read the "so called assistance" that was provided and understand I'm not some completely useless person "like you all suggested" and as a result I gave blunt responses in return showing my appreciation for the RUDE/little assistance and belittlement I received for you.

I fielt my replies were warranted, considering the attitude and belittlement I got from a number of you. All because I don't have access to a "very expensive" FLUKE DMM!

• My questions of how to confirm accuracy of a DMM, fell on deaf ears.

• My questions of the products number/model number of the voltage meters in Victron products, so I could answer the above question, fell on deaf ears.

• My question about how you can all guarantee the accuracy of Victron voltage meters when you all told me that unless a DMM is calibrated every year its not guarantee accurate, so I clearly asked how and why the Victron units can/are still considered accurate when they aren't calibrated every year? This fell on deaf ears.

• How can Victron products be guaranteed to have accurate Voltage if they're not regularly calibrated?

• Exactly what accuracy percentage does a Digital Multimeter need to have to be considered accurate enought to perform testing?

^^^These are SIMPLE QUESTIONS that will help MANY future Victron users and save them from having to create posts/questions when it's already been answered (the whole point of this community according to community guidelines)...

Let's watch you delete my account again for trying a second time to ask BASIC questions all because you assume I'll abuse you - The difference is that if you actually provide clear answers and don't provide VAGUE information, or try to waste my time asking for irrelevant information and/or imply I'm useless, then my replies will be respectful.

If you waste my time again, be rude or vague you will get blunt/rude replies in return - Not sure why you're surprised by this.

* I've been told I'm blunt due to my Autism, but that won't change the sour people who have been offended at my responses to them after they wasted my time, or implied I am useless (which in itself) is very insulting to me!

^^^ You offended me and/or wasted my time first before I gave it in return...

not-a-hard-question-to-answer asked
Fra commented ·

2 Answers

Question about accuracy of the Voltage meters in Victron MPPT's and Smart Battery Sense?

Answering these questions should help other Victron users who notice voltage variances on their Victron equipment gauge whether there could be an issue, or whether what they're seeing is considered normal.

1) What is the Volatge metering accuracy of both the internal MPPT and Smart Battery Sense Voltage meters?

2) What is the voltage meter model/part number and manufacturer?

3) How can one be sure they're accurate if they aren't calibrated/checked every year like digital multimerers need to be, especially after 1 year?

4) Testing of equipment is a waste of time if you're not using a guaranteed in spec digital multimeter, Correct?

5) What is the minimum accuracy of a digital multimeter for a reading to be considered "correct" and/or accurate?

not-a-hard-question-to-answer asked
Fra commented ·

1 Answer

BVM-712 SOC not accurate

This is my second season with the following setup:

  • WFCO-8955 Power Center
  • Victron BlueSolar MPPT 150/35
  • 3x Battleborn BB10013 100 Ah 12V LiFePO4 Deep Cycle Battery
  • Victron BMV-712 Battery Monitor
  • 3x KIT1010 90w Zamp Solar Panels

I have the BMV set exactly according to the battery website (see screenshot):


The issue that I’ve always had is that the displayed SOC decreases much quicker than the actual SOC:

  • After connecting to shore power, the batteries will quickly charge and SOC will show 100%, but if the system remains connected to shore power for a day or two, the SOC will drop from 100% to as low as 80%, lower if connected longer.
  • When boondocking/drydocking, the SOC will eventually display 0% yet the batteries will continue to put out power for days, running the refrigerator, pump, lights, etc.

This leads me to think of these possible issues:

  • Wiring is incorrect. I've had the installer and battleborn/dragonfly check the wiring 3 times. Everything has been verified correct (see screenshots).image008.jpgimage004.jpg
  • The battery parameters for the BMV are not correct. This has been checked many times by battleborn/dragonfly.
  • The algorithm for SOC is not correct. I can't believe this is true since most people say how accurate this is.
  • The batteries have much more capacity than 3x100 aH=300 aH. If the battery bank was substantially higher, then this might explain why the SOC drops to 0% yet I still have power left in the batteries, but it wouldn't explain why the SOC drops even when connect to shore power.
  • There's something wrong with the WFCO-8955 charger. There is almost nothing to configure on this except the Li switch (which is correct).

As a possible fix, could I increase the battery capacity? Is this recommended?

Battleborn/Dragonfly says that the system must be completely charged and discharged to 0% 4-5 times before the BMV "learns" the true capacity of the batteries. I haven't seen this documented and so I don't understand how this would work. Is this true?

Anyone have any other ideas? I'd love for this to work, but with the current situation, the SOC is useless.

ciphersix asked
klim8skeptic commented ·

6 Answers


Beste lezers,

sinds een paar dagen valt mijn accuspanning weg tot rond de 10.6 volt. Op de dag laad mijn zonnepaneel hem wel gewoon bij. maar zodra zon weg is of multi plus uit is zakt hij in. Bijgevoegd heb ik 2 foto's waarop meer info is te zien. Hopelijk kan hier iemand iets mee. Vanavond laat ik mijn 2x 180 Ah accu's voor de zekerheid nog even testen.

met vriendelijke groet,




a3rijns asked
kevgermany answered ·

1 Answer

Shunt stauts isn't accurate.

I installed a Victron shunt with my new Dakota lithium starting battery. The shunt is wired correctly and I can see draw when I start my engine or when my graphs are on. I can also see the charge when running my engine or charging wit the charger. I've checked status while I am fishing and the draw down and recharge seems fine. The last two trips I check the status before trailering my boat and the shunt showed 92 on one trip and 94 on the other. I check again when I got home and both times the shunt showed 100%. I hooked my charger up yesterday and it charged for about 35 minutes before going into float mode so the battery was not at 100%. When I installed the shunt I charged the battery to 100% and synchronized the shunt. Any ideas?

aglowack asked
aglowack commented ·

2 Answers

Smartshunt accuracy

I have a LIFEPO4 100ah, my manufacturer states it will work between 14.56v and 10v. I know that 10v is not a viable voltage, however at 12.56v its showing as around 15% SOC.

Am I doing something wrong? It's all wired in correctly and seemed to be pretty accurate on my previously lead batteries. All settings change to lipo.


James Dowse asked
nickdb answered ·

2 Answers

Inaccurate and poor absorption on SmartSolar: An Update

I'm posting this on behalf of another user, @Solvan.

Solvan recently posted the results of testing his own Smartsolar units, as well a summary of testing other units stocked by his vendor. These tests demonstrated gross inaccuracy in the units measurement of the current, resulting in premature termination of absorption charge, and incomplete daily charging.

The previous relevant threads can be found here and here . Since posting this, two things have happened:

- Multiple other users have reported the same experiences: @bigbillsd (here), @lnanne (here) and @RedRover (here). Note also, that this topic has come up previously, and been sidestepped. Multiple times, in fact.

- Solvan himself has spoken with me, and informed me he has been completely locked out of the forum, following posting this final thread .

Furthermore, he received an email from Guy Stewart, the moderator here, explicitly stating his posts have been "moderated" as a result of exposing the faults in the MPPT units, and instructing him to provide any further information behind closed doors, instead of publicly releasing it for other owners awareness. He has provided this email, and his response, attached below.


Additionally, the vendor, who went out of their way to help Solvan test his, and the other units, is now reportedly unable to return the units, for fear of the same persecution, leaving them thousands of dollars out of pocket.

It is also worth noting that Guy Stewart is part of the management staff at Rainbow Solar - of which a large pat of their business is the sales of Victron equipment.

I am very curious to hear if any others are experiencing the same difficulties with their units accuracy, and whether people think this is an acceptable standard of customer support, considering this overtly suppressing negative feedback in an official support service.


straightup asked
mvader (Victron Energy) edited ·

4 Answers

AC / DC Amps for AC In charge limit ?

ON the Color control settings ( or directly on the Veconfig / mppt settings) , we can limit the ac in current .

I just want to make sure i am not making a mistake.

200 ah at 48 v batteries. I want to limit the charge current to 10% to 15% of my Ah. So 200 ah x 12% = 24A. So i limit my mppt charger to 24 a . These are easy, they are DC Amp.

For the settings of my multi' gia ve config or ccgx color control, i can limit too my charger current limit (ac in). When i am on the color control page of themulti and can set the current limit ( 25 a on the picture), are these DC amps ',hence 25 a is ok, or are they AC amps ? If AC, then I should set a limit of : 25 a x 48 v = 1200 w ÷ 0,85 efficiency = 1411 w ÷ 230 v = 6.13 A AC . Is it this "6" i should enter as the limit ? I do not think so but prefer to check .


Herve RV Nizard asked
Kristof G. commented ·

2 Answers

AC loads are constantly off, Quattro, CCGX

When I had my Multi, the indicated AC loads were always within reasonable watts of actual load.

But once I installed my Quattro, I'm noticing a fairly constant difference of around 20%.

I have "has DC system" enabled and it seems to try and fudge that difference mathematically as DC system draw, even though the Quattro is the only consumer in circuit.

The current drawn, as shown on the BMV, is in lockstep with the BMS's reported current draw.

For example, right now the BMV is showing ~300W drawn from the batteries (confirmed by BMS).

The CCGX is showing AC loads of 180W, and a constantly varying number "DC System" of 20-50W, with the rest just... unaccounted for.

With higher loads (>50A 24V DC) the difference is somewhat closer. So a 1800 W draw shows 1200W AC loads, some variation of 100-300 "DC system" with the rest unaccounted.

Again, there is NO other DC consumer other than the Quattro.

Also based on math, that 1200 load is not right at all.

I considered the difference between resistive vs inductive loads -and with the lower draw example that might be true; since we have a lot of "wall-warts" for phone, computer, mifi, and other misc AC/DC converters.

But with the higher example, I simply turned on a 1500W kettle.

geomz asked
ben commented ·

4 Answers

What is the maximum AC current output of Parallel 15kV Quattro Inverters

Good Afternoon, I am currently designing a hybrid battery system across three phase, the phases are unbalanced and can't be fixed due to the sites businesses. I know that the max AC amperage output is 2 x 100 amps, on a 15kVa Quattro. but if I install 2 per phase does that give me a total of 400 amp output per phase or I am miss reading the spec sheet. My Ampage max output is at its highest around 12 midday and i am also installing 100kWh of BYD batteries that will move up 200kWh by mid-year.

Please can someone just confirm what the max AC amperage output is in this situation

leeprior asked
Wessel Wessels commented ·

6 Answers

Innacurate SmartSolar current measurement.

Hi everyone,

I've got a SmartSolar 100 | 50 MPPT, and a Bogart Engineering Trimetric battery monitor.

I'm noticing there's a notable difference with the amps the SmartSolar says it is putting out to the battery, vs what the Bogart says is coming in. With all output loads isolated, the SmartSolar seems to over read by 5% ie 5% higher than the value read on the Trimetric.

The Trimetric measures using a precision shunt, with sense wires routed well away from any load lines. It's been checked with two independent instruments and I'm confident of its accuracy.

Is this level of error acceptable in Victron units? Because it's effectively ruining any use of the historical data from the SmartSolar unit, and I have concerns about its implications if I decide to switch the Trimetric with a BMV unit.

solvan asked
mvader (Victron Energy) answered ·

2 Answers

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