Mppt 150/70 grounding issue

I have an mppt 150/70 connected with bmv700 , Phoenix 24/12 converter and Phoenix multiplus 24/3000 Recently had cable melting issues on the 12v side and rewired everything.

All 12v accessories ground to the Orion Not the chassis

The 24v house battery bank is also not grounded to the chassis . If I connect the 12v or the 24v black wire to the chassis it goes up to 17v and wires get warm And the Mppt 150/70 reads 0v on the Pv side if I keep the 12or 24v floating (not grounded to chassis all is ok and the POV voltage shows again charges etc

I have a smaller mppt on the 24v starter batteries which also has a 24/12v converter for audio system but these appear to be fine and have no influence even though they are grounded to the chassis of the bus.

It seems that only the mppt 150/70 has issues and therefore anything 12v inside the bus cannot use a earth to chassis anymore hence the rewiring.

Although it all appears to work properly now it has me scratching my head any thoughts?


gunnadoo asked
gunnadoo answered ·

5 Answers

ESS heavily discharging battery when SOC has reached 100%

Hi Victron team,

I have configured an ESS parallel system based on the following components: CCGX running on Raspberry PI (v2.20), MultiPlus 48/5000, BlueSolar MPPT 150/35, PV inverter on AC IN and CAN REC-BMS controlling charging/discharging of 400ah 16s Sinopoly LFP battery.

When the battery reaches 100% SOC the Multi switches to inverter at full power and starts discharging the battery into the loads/grid. Also, even the MPPT is ESS/CAN controlled it continues to supply current into battery at 100% SOC.

Please see the attached pictures. In pictures number 1 and 2 you can see the battery at 100% SOC as is reported by the BMS and the charging parameters. The max charging voltage is correctly lowered and displayed at 52.8V. At any SOC below full this parameter is 55.2V

In picture number 3 you can see the MPPT parameters. Why is the charge voltage 60.8V? This value shouldn't be controlled by the BMS?

In picture number 4 you can see how Multi discharge the battery right after this reaches 100% SOC

Finally, in picture number 5 you can see how MPPT continues to charge the battery in battery hysteresis period (max charge voltage still at 55.2V)




mihair asked
AvB answered ·

11 Answers

Does Venus GX try to re establish lost internet connection?

Hi all

I am puzzled by loss of VRM connection by my Venus GX after the local 4G connection was lost for 6 hours.

My other internet dependent remote sensor and control devices all came back to life but not the GX. It is connected by ethernet cable to a router with a USB 4G dongle.

The router automatically reboots the USB when the 4G internet does not respond. The system worked flawlessly for 6 weeks prior to the loss of the local phone network. As yet I have not configured a VPN from home to check the status of Venus locally (on the to do list, thought I had it nailed before I took the box 13000 km to destination but epic fail).

Soooooo....Does the Venus seek the portal again if the connection goes down or do I need to reset or reboot it?



oldcrow asked
oldcrow answered ·

3 Answers

Victron connect app not reading out smartsolar 150/85


Sinds the last update of the victron connect app for Android, it don't reads out the settings Pages of my smartsolar 150/85?

Also the history page is not showingany information anymore, like it got cleard. ?

On windows the victron connect app works whiteout problems!

Ps. I'm using an Moto 5G, and before it workt whiteout problems!!

Has anyone an idea what's going on here?

Thanks already,

friendly greetings, feeedom

freedom asked
freedom answered ·

2 Answers

Smart Battery Sense with no MPPT - just mobile phone

Hi Victron team,

Thanks for your other responses. I'm assuming we can sell the Smart Battery Sense if customers just want to monitor batt voltage via their mobile phone APP and they have no other Victron MPPT's or devices in the system. I read the product documentation which covers how to set up a network between MPPT's etc, but not just having the Battery Sense in isolation.



David asked
David commented ·

1 Answer

Fronius colour gx quattro


Just a quick question is there a option of hardwiring the commication of the said 3 items on a install ?



mikeb asked
wkirby answered ·

2 Answers

12v campervan set up help


I have a 250 watt single solar panel and victron 100/20 smart solar mppt going into 2 x leisure batteries (12v set up) in my campervan.

1. Is it correct to connect the earthing point on the side of the controller to the negative terminal of my leisure battery....

2. I am using the controller with victron app on my iphone.....the controller came with the jump pins 2 and 3 connected (using the connecting block). Is that the best location for normal use with my set up?...

Many Thanks

plinky asked
plinky answered ·

2 Answers

Grid assist failure


I have 2 MultiGrids 48/3000 in parallel mode in a 1-phase ESS-system.

ESS is configured:

Limit inverter power "ON"

Max. Inverter power: "4800W"

When the loads are bigger than 4000W the power over that comes from the grid and not from the MultiGrids. It seems that it is impossible to use more then 2000W at the AC-out of one MultiGrid ?! The temperature in the room where they work is +20°.

What can I do to get more power from the MultiGrids?

Best regards


maha asked
mvader (Victron Energy) commented ·

1 Answer

Re ESS setup with multiplus 2 with VE configure 3

Re ESS setup with mulitplus 2 with VE configure 3

1: to setup all the settings do you need a Venus unit to set the mode 2 and 3? as the VE config 3 won't do it.

2: I am using the AC2 output as is were my PV inverter is hooked up to as per 28/05/18 document.

3: I can't get it to charge at all during the day at all with full PV inverter power export back to the grid, it shows as a negative VA on the VE bus monitor, which is correct. so what conditions need to set to make it charge?

4: So at night time it wont self consumption just stuck on the grid input only. latest ver of VE config3 and inverter firmware etc Unit firmware is 2625430 and VE config3 90.04.206.

5: I have ask the dealer, they said they were hard to setup and didn't know enough about it, or help.

Export of settings of the unit
TAB: General
System frequency 50Hz
Shore current 2.0 A
Overruled by remote checked
Dynamic current limiter unchecked
State of charge when Bulk finished 85.0 %
Battery capacity 40 Ah
Charge efficiency 1.00
TAB: Grid
Country / grid code standard New Zealand: AS/NZS 4777.2:2015
LOM detection AC input 1 Type A (grid code compliant)
TAB: AS/NZS 4777 grid code settings
rise-in-voltage protection U> 248.0 V
Power ramp time 60 seconds
Enable DRM0 functionality unchecked
Fstop for sustained high frequency operation 52.00 Hz
Volt-Watt curve voltage V1 207.0 V
Volt-Watt curve level at V1 0 %
Volt-Watt curve voltage V2 220.0 V
Volt-Watt curve level at V2 100 %
Volt-Watt curve voltage V3 244.0 V
Volt-Watt curve level at V3 100 %
Volt-Watt curve voltage V4 255.0 V
Volt-Watt curve level at V4 100 %
TAB: Inverter
PowerAssist checked
Assist current boost factor 2.0
Inverter output voltage 230 V
Inverter DC shut-down voltage 37.20 V
Inverter DC restart voltage 43.60 V
Low DC alarm level 43.60 V
Do not restart after short-circuit (VDE 4105-2 safety) unchecked
enable AES checked
Load for starting AES mode 25 W
Offset for ending AES mode 46 W
AES type search mode
TAB: Charger
Enable charger checked
Weak AC input unchecked
Stop after excessive bulk unchecked
Lithium batteries unchecked
Storage mode checked
Use equalization (tubular plate traction battery curve) unchecked
Charge curve Adaptive + BatterySafe
Absorption voltage 57.60 V
Float voltage 55.20 V
Charge current 12 A
Repeated absorption time 1.00 Hr
Repeated absorption interval 7.00 Days
Maximum absorption time 8 Hr
TAB: Virtual switch
TAB: Usage
Virtual switch usage Do not use VS
TAB: Assistants
TAB: Assistant Configuration
ESS (Energy Storage System) (size:1632)
*) System uses Gel or AGM batteries
*) The battery capacity of the system is 40 Ah.
*) Sustain voltage during the first 24 hours of sustain 46.00 V.
Sustain voltage after 24 hours 50.00 V.
*) Cut off voltage for a discharge current of:
0.005 C= 48.00 V
0.25 C= 46.60 V
0.7 C= 45.60 V
2 C= 44.80 V
*) Inverting is allowed again when voltage rises 1.20 V above cut-off(0).
*) The solar converter will start reducing its output power at 50.20 Hz.
Output power will be reduced to minimum when the frequency is 52.70 Hz.
The converter will disconnect when the frequency is higher than 53.00 Hz.
*) Total installed PV inverter power is 2000 Watts.
Total installed PV panel power is 2000 Watts.
*) Relevant VEConfigure settings:
- Battery capacity 40 Ah.
- PowerAssist checked
- Lithium batteries unchecked
- Dynamic current limiter unchecked
- Storage mode checked

Total size of all assistants including the required
(hidden) system assistants is: 1705

Rob Duthie asked
Rob Duthie answered ·

9 Answers

SKYLLA- TG 24/50 3- Phase REM function

Hi. Can anyone provide some information about the remote function (REM) on a SKYLLA- TG 24/50 3- Phase charger?

We need to install a remote ON/OFF function on a charger built into an existing system. We can't access the charger until the job is actually done, and even then access will be difficult and time limited, so we need to get it right first time. It can't be tested until the system is rebuilt, and it will have to be stripped again to make changes which is a big job, so you can see my problem.

The user manual (Manual-TI01170-EN - 4.12, p23) is quite vague about exactly how REM functions. The manual instructs us to connect a remote switch between REM and GND but it doesn't tell us what happens when the switch contact is made. Does connecting REM to GND enable or disable the charger? Sorry if this seems very trivial but we want to be 100% sure as it will involve a relay and PLC software on top of the access problems.

Thank you.

robertg asked
mvader (Victron Energy) answered ·

1 Answer

Inaccurate DC input current readings from MultiPlus inverter

I have noticed that the "DC in" reading on my new EasySolar 24/1600/40 is quite inaccurate. This has been confirmed using a multimeter on the positive DC lead to the unit - when the multimeter reads 2.2A, for example, the inverter is reading 3A (read using VEConfig). When the multimeter is reading 3.9A, the inverter is reading 5A.

So as you can see, the inverter is reporting >20% too high. This is a problem, because in combination with a BMV-712, this reading is used to calculate DC loads. When the inverter is reporting too high like this, quite often I see a "negative" DC load, since the inverter alone is reporting a higher current draw than the total current from the battery (as read by the BMV).

Is there anything which can be done to make this more accurate? Perhaps the accuracy improves as load increases, but it is still quite bad at low loads.

aeneby asked
aeneby commented ·

1 Answer

After Firmwareupdate: Multi restarts all the time (after every ~10sec)

Hi, I updated the CCGX from 2.08 to 2.20. Everything was Ok so far. Now I connected the Multi 24/5k and the Multi restarts all the time (after every ~10sec) . With the old Firmware (2.08) that was not happen.
Any ideas and how can help?

Walter Drebinger asked
Walter Drebinger commented ·

3 Answers

Unbalanced load in a 2x Multiplus II 3000/48 system (Germany)

Hi there!

The new Multiplus II has anti-islanding and a lower standby-consumption than the classic one at the same price (I hope it will be the same quality anyway ;)). But it is only available as a 3000VA Version. In an ESS-system this normally would be enough to providie enough power for the most devices, e.g. a washing machine. Unfortunately if you strive to get 100% self consumption in summer you can only use one device at the same time. So in an average household you need at least two Multiplus II if you don't want to turn the lights or TV off when the washing machine is running.

There are countries with a monophase utility grid like some areas in Italy, which would make this easy. But there are also countrys with a 3-phase grid utility like Germany.

Now in Germany and other countries the maximum unbalanced load of the phases is allowed to be 4,6kVA. Btw: Is that why there isn't a 5000 Multi II, yet?

I have one question about this "problem".

(How) can I provide 4,6kVA to all three phases with the ESS without buying a 3-phase Multiplus 5000 system with external anti-islanding? I think (but don't know) that 2 parallel MP3000 aren't allowed in only one phase, although that would be the best and cheapest solution with an energy meter and phase compensation. When using a 3-phase 3000-System and there is a load of 4000W on L1 - what happens? Two parallel Multi II could cover this to 100%, no matter on what phase it is needed (when having the correct power meter). But is it allowed?

If it matters: there would be a 20kVA-Fronius-Symo-3phase-Inverter at the AC-In of the Multis (because of the 1:1 rule) and a small 1,2kWp DC-Victron-MPPT.

Thank you very much!



porcini asked
Guy Stewart (Victron Community Manager) commented ·

1 Answer

120 vs. 144cells on an MPPT 100/20-48


I noticed that you offer the 100/20 as a 48V-Version, although that product isn't promoted on the VE-website?

The advantage is that this controller is a very cheap solution as the 150/35 is almost twice the price. But it's also a niche because there come a lot of problems with the 100V limit. I will explain my thoughts.

At normal conditions it will be possible to use both, two 60-cell and two 72-cell panels in a row.
But when it is getting hotter there is a problem when using two 60-cell panels combined with a lead-acid battery. The cell temperature entails the MPP-Voltage to be at the same level as the battery charging voltage, so the charge controller has to set its operating point above the MPP of the PV. That means losing energy. If an equalize-charge is neccessary that could even be a problem. Probably a solution would be to use Pylontech LiFePO4 and such batterys, as they operate at lower voltages. But in an off-grid-system these aren't allowed?

When it is getting colder two 72-cell panels are a problem, too. The open circuit voltage rises above the 100V limit. I don't know how much tolerance there is until the charge controller gets broken, but in winter it would definitely exceed its specs. So there are a few questions I have:

1. Does this charge controller have a PV-overvoltage-protection?

2. When using ESS with feed-in the MPPT normally works at the MPP of the PV. Is it getting more careful when it works near the limit and avoids to get over 100V if that is possible (feed in enabled, batterys empty) or does it still try to find its MPP no matter if that would be above 100V?

3. The bigger 150V models don't work above 145V. How does the 100V-Version? Does it still work at 101V or will it shut down and show an error? At which voltage that error appears?

4. Do you think that the charge controller can be used with 144cells when reaching 102V in the winter (with losing warrenty) without getting broken soon?

5. Who is this controller designed for? In Western Europe it's not an optimal solution. Neither with 120cells nor 144cells. Probably 144cells in Africa would work great.

Thank you!



porcini asked
porcini edited ·

1 Answer

Certified Fronius with Victron

Hi Guy and Victron (thanks for previous 5 star answers)

An installer is asking this new question:

I have an on grid homeowner, who has an existing Certified Fronius 5.0 (intended to go Selectronics when batteries were added) who is now thinking about Victron MultiGrid-II. Will the Victron do the frequency shifting with the Cert Fronius inverter ok?

Thanks again.

David, DPA Solar

David asked
David commented ·

1 Answer

BYD/ Phoenix VE Bus inverter

Hi Guy and Victron Team,
An installer is asking if BYD batteries can be connected to a Phoenix 3kW (VE Bus) inverter, 2 years old in an off-grid system. I'm assuming that if we update firmware and install a CCGX etc etc, it will operate ok?
Thanks again for your ongoing help
David DPA

David asked
David answered ·

2 Answers

Cascading inverters

Already posted this at Victronlive, but it seems like that is transitioning to this forum, so posting here as well.

I have an existing 48V 5kVA Quattro fed DC from 13.5KWp PV and 1200AH battery bank.
Power cuts are not infrequent and I have islanded some essential loads to be purely fed from this system.
I want an offgrid system, and I'd prefer not to add ESS unless I have to.

I want to add another identical Quattro to the system and add some less essential loads.

I understand how to conventionally parallel them.
And that it will effectively give me a 10kVA Quattro, but only the same features as I already have.

Q1. I would like to know if connect them in and upstream -downstream relationship would that give me the ability to have 10kVA available at the downstream inverter and the ability to loadshed one of the AC outs if my battery SOC was low. As I now would have 2 AC outs.

Q2. Would this also give me the ability to have a second battery bank that be configured to use a different DOD?

I realize the downstream inverter should not feed back power to the upstream inverter as the downstream inverter will not respond to a frequency rise like a Fronius PV inverter, if the upstream battery bank was full, the feed-in power would have nowhere to go.

Q3. Assuming this configuration is feasible. Would it exclude the addition of a Fronius PV inverter on the respective AC out of both inverters? I may add 5VA of PV inverter at each level of AC out, (1:1 rule applies), but because the everything is synced at the upstream inverter's frequency, it would appear that the 1:1 rule is now broken, is this permissible in the settings?

Q4. Assuming a single battery bank and no additional PV inverters, for the moment are there any special setting requirements and which assistants would be best suited to achieve this?

Thank you

Phil Gavin asked
Phil Gavin answered ·

5 Answers

BYD and Quattro never go to float?


Have set up VEConfigure on a Quattro and byd

As per settings

Battery type lithium

Charge curve fixed

Absorbtion voltage 55.2

Float voltage 55v

Absorbtion time 1 hr

When charging the battery’s the inverter goes in to absorbtion but it hasn’t charged over to float?

Is there something I am missing or is these normal and should just rely on the byd bms?



mikeb asked
mvader (Victron Energy) commented ·

2 Answers

Feature request MultiPlus

Hi there,

Currently, an off grid MultiPlus with an AC coupled inverter is not able to automatically recover from a LVD: once the MultiPlus decides it needs to LVD, the "grid" goes down and takes the PV inverter with it.

So at this stage an additional charge controller with it's own set of panels is required to allow the system to automatically recover from a LVD.

It would be great if the PV assistant on the MultiPlus (I assume this is where this functionality would likely be implemented or possibly it could be in VenusOS too if VenusOS would be able to get the required level of control of the MP) would have a feature called "Recovery" or something along those lines that can be programmed with VE.Configure.

It would work something like this.

Imagine a LVD of 47.5V. When the battery voltage reaches 47.5V, the MP will stop inverting and wait until the battery voltage reaches 51.5V. As mentioned above this will currently never happen without intervention.

At set times of the day, for example in the morning, the MP could enter a recovery mode with the following parameters:

- Recovery V: 47V
- TTR (time to recover): 3 min
- Max AC load: 3A
- Start time: 09:00
- Interval: 15 min
- Stop time: 11:00
- Max attempts: 3

In the above example, the MP would start inverting at 09:00 provided the battery V >= 47V and the AC load remains <=3A. It will wait 3 minutes (TTR). If during that time, the MP senses that the batteries are being charged (ie. AC load = 0A as PV inverter is powering the loads and it has started to charge the battery, the recovery has started successfully.

If either battery V drops below 47V (in this example) or the AC load exceeds 3A while battery V is still below LVD, the MP will stop inverting and try again after "interval" minutes for "Max attemps" number of times. It will also stop attempting to enter recovery mode after 11:00.

A really fancy version would use the time of sun rise for a particular date instead of a fixed start time.


jbakuwel asked
mvader (Victron Energy) commented ·

2 Answers

BMV 712 Average Discharge Data Not Displayed In Victron Connect App

Dear group

As the title suggests, I have an issue where the data for average discharge remains at 0ah regardless of how many synchronisations have occurred.

I have played around with various settings & given the system time (days & weeks) to calculate & display this useful little nugget of information, but all I get is 0ah.

I am currently running 4 x 120ah flooded lead-acid batteries.

The BMV 712 is up to date (at the time of writing) & the android phone VictronConnect app is also up to date.

Thank you for reading.

Dave asked
mvader (Victron Energy) commented ·

3 Answers

AC Cooling power needed for inverters

Hi I am designing a sealed and insulated room for 9 x 15kW Quattro inverters. and are looking at what size AC I would need to keep things cool.

Inverters could be running at full power for up to an hour at a time. What would be a reasonable Quattro efficiency rating, to size a air conditioners cooling power?

jon-lowbank asked
mvader (Victron Energy) answered ·

3 Answers

lights turning off

When we turn on the LED lights the MPPT momentarily turns off the load, consequently no lights for about 3 seconds. The MPPT model is 75/15 (SCC010015050R). Solar input is 500 watts at nominal 24 volts. Lighting load is approx.60 watts maximum per switched circuit.

jrohde asked
jbakuwel answered ·

1 Answer

ess mode #6 generator continues charging

.Hello @mvader, @Guy

I have an issue with my three phase ESS, BYD being overcharged while running on generator

the Quattro keep on charging the battery with small current even when soc is 100% and CCL is reported as zero by BYD

I had to switch off the generator for fear of tripping on overvoltage ( reported by BYD 57v)

the firmware is v2.20~67 ) DVCC= on charging current set to 0 and CCL = 0 (reported by BYD)

this happens when only running on the generator on GRID input it stops correctly the charging

to check I changed the soc limit to 70 and dvcc charge current limit to zero


When running on generator the Quattro keeps on charging the battery. the solar chargers and pv inverters have been correctly throttled

the charge current changes from as low as 1.5 amp to 15 amp

Tthe Quattro keeps on toggling between bulk and passthrough mode

should it not remain in passthrough ?

the same thing happens when the soc is 100 % and the mode selected is kept batteries charged

Anil Ghatikar asked
Anil Ghatikar commented ·

2 Answers

What would cause a download error for Remote VEConfigure

I get the error shown below when attempting to download the VEConfig file via CRM for my MultiPlus I viewed the video about how to use the "Remote VEConfigure" feature of the MultiPlus 12/3000/120-50 120V . But when I open VRM and attempt to download the VEConfig file for the MultiPlus, I get the following error. I have connected to the MultiPlus directly via USB to use VEConfig, so I assumed the remote VEConfig via VRM would work as well.

What would be the normal cause of the error below?

No VEBus Product was found

Error Code: mk2vsc-33


Steve Mullins asked
Guy Stewart (Victron Community Manager) edited ·

1 Answer

VictronConnect or Android re-asks for USB preferences now and then

A minor niggle this, but occasionally when I start the Victron Connect app up on my android phone (Samsung) I get an annoying "app preferences" dialogue box pop up, asking the following....

"Allow the app VictronConnect to access the USB device?"

"Use by default for this USB device"

I tick to accept & ok, hoping that it will never ask this redundant question again, but sure enough, it does. Sometimes a week will pass & sometimes its an hour later.



Dave asked
Dave answered ·

2 Answers

Frequency shift affecting clocks

G'day, I have a customer that we installed a Fronius 5kW AC Coupled to a 5kVa Multiplus in an off grid install. I've also DC Coupled in a SmartSolar and connected to SunGel Carbon Gel batteries.

The customer is now experiencing his AC powered clocks running fast and I suspect it is caused by frequency shift as the Multi controls the Fronius.

Is there a solution to remedy this issue? Thanks in advance!

matto asked
Guy Stewart (Victron Community Manager) edited ·

1 Answer

What is the output derating for a Orion tr 48/24-16 at 50 degrees Celsius?


I was wondering what the temperature derating is for the Orion Tr dc dc converters. We are running 3 in parallel. The control box may get to 50 degrees Celsius. Thanks.

craigdeselectrical asked
Guy Stewart (Victron Community Manager) answered ·

1 Answer

Best mppt for my array

Hi, I have a few panels, of different sides. Which mppt should I use?

mvader (Victron Energy) asked
mvader (Victron Energy) commented ·

2 Answers

Venus without a Multi/Quatro

I'm working on a system that may end up using a Phoenix inverter rather than a MultiPlus due to cost and size constraints. Venus devices (Cerbo, CCGX, etc) are inverter-centric and there's a large portion of the U/I that simply doesn't apply to a system like that: AC in/out and inverter tiles all will be blank.

First: Is it true Venus doesn't communicate with Phoenix VE.Direct inverters?

I realize that the blank tiles could simply be ignored (or hidden by changing code which I could do), but is there a better solution to a central monitoring and control for a system with solar and batteries? This is an RV so there would be a DC system as well.

Kevin Windrem asked

2 Answers