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Launch of the Lynx DC Distribution documentation manual - Feedback needed

Hello Community,

I have just published the Lynx DC distribution manual


I would appreciate any feedback, suggestions for how it could be made better or clearer, or any questions you have that it doesn't answer.

Thanks, Guy

Guy Stewart (Victron Community Manager) asked
rstueckle answered ·

5 Answers

Backup Generator in parallel with solar, DC loads only

I've got a 3.6 kW (DC peak) solar array fed through three parallel MPPT 150/100's to feed a LI battery bank. The system feeds two small DC pumps that need to run continuously. I want to add a small AC 1-phase generator to feed the loads and charge the batteries if the battery voltage gets too low. Is there a Victron product I should use to rectify the generator output, limit current, and control charging? Can this system operate in parallel with the solar/MPPT's or will there be issues with the controllers fighting each other?

alex-morrison asked

0 Answers

Will the Fuse LEDs on Lynx Distributor illuminate without the 4-pin cable supplied with unit?

Trying to use the Lynx Distributor (and Power In) without the Lynx Ion Shunt or BMS (using BYD batteries). I had assumed the Fuse LEDs would illuminate with a working fuse in place and powered, however a line on the old Victron Live page for DC Distribution Systems suggests that this small data cable is used to power the LEDs (rather than taking power from the busbar itself). I cannot get the LEDs to illuminate - are the LEDs useless unless using the Lynx Shunt? Because Lynx Shunt uses CANbus, it cannot be used in conjunction with BYD on a CCGX (though I think VGX would support it).

midsummerenergy asked
karavanlife answered ·

9 Answers

Procedure for updating DC wiring with running inverter

Dear community,

can you please point me to the recommended procedure for updating battery-side wiring (adding MPPT to an emergency power system) with minimum impact on the loads? Would it be enough to switch off inverting (physical switch on Quattro) and disabling charging (VEConfig), then switching of the (Pylontech) batteries? Or would this lead to the grid throughput be switched off anyway, as the Quattro is not designed to run w/o batteries?

The system is powering two flats, I would like to reduce impact for our tenants. The work itself will be done by a qualified electrician.

If switching off the batteries is not an option, maybe it is a good idea to add circuitry to optionally "bridge" the Quattro with a transfer switch, and then switch off the Quattro completely? It seems to me that this would ease maintenance. Any issues with that?

Thank you.

tobyfw asked
Alexandra answered ·

1 Answer

Negative DC Loads while charging, positive while discharging (increases with load)

Before I start I want to say I've read through quite a few posts already where folks are describing negative DC loads, however I have not found anything that quite explains what's going on.

Some background on my setup: I live off-grid and run my home off our solar/battery setup. I recently switched over to a new 48V battery system I build, we have all new hardware, Multiplus II 48V, two victron charge controllers, smartshut...etc.

I see negative load on the DC side (indicating a charge coming from DC). This is odd as other than our charge controllers we have no other DC charging sources. However if we have a large AC draw (3Kw when running our well pump) DC load spikes to around 100-200W.

I'm perplexed because I never saw this on our previous system. What could be going on? Below is a schematic of our system:


During the evening (no solar input):


During the day (solar input/net positive load to battery)


I am using my own graphing system but my Venus device displays the same data as well.

hummingbear asked
mvader (Victron Energy) commented ·

4 Answers

Battery shows "Idle" state while in DC Load

Hello everyone,

The Battery state shows "Idle" even though there is a discharge of DC Power 17W.

do I need to change any values or settings to set the benchmark or limit so that the system can understand it is in discharge mode ?.

The system has smartshunt 500v with cerboGx & smartSolar MPPT all connected through VE.direct cable.

Please let me know.

@Matthias Lange - DE - any opinion from your side?


jimz asked
jimz commented ·

1 Answer

VRM Shows wrong energy flow direction
  • vrm shows a wrong energy flow into the invertor direction. But, technically there is no invertor connected in the system. Instead, I was expecting the energy flow into the DC Power direction (system is in bulk charge mode with DC load connected through smartshunt 500v).

  • Also, i can hear a buzzing high pitch noise from smartShunt 500 which is clearly audible in a noise free environment. is this an issue with my piece?. i can see some of the users reported the same with smartShunt 500 model.

** all negative connections (PV Charger & DC Load) go from smartShunt terminal

Can anyone please shed some light on what is going on here


jimz asked
jimz answered ·

2 Answers

Fuses Pylontec / MPPT 450/200 / MP II


could please anybody confirm that the fuses and cables I'm using are correct in my installation?

I'm not 100% sure...

I have installed 4 Pylontec 5000 batteries (4,8kWh each) in 2 groups of 2 batteries

Connected every group with (original pylontec) 25mm cables and protected by 100A MIDI fuse each group

The MPPT 450/200 goes with a 30cm, 70mm cable to the 200A fuse on the bus bar.

The multi is connected with a short 50mm cable and protected by 100A midi fuse.

Is there any problem with this installation?

Thank you!


guru77 asked
Alexandra commented ·

2 Answers

ac and dc coupled

i am going fully offgrid,, using smartsolar for dc coupling, and also would like a mutliplus 2 5kw to grid refererence a pv inverter, the pv inverter i have is a aurora power one uno, would that be ok to run with the multiplus 2 please

dave-witcher asked
Phil Gavin answered ·

1 Answer

BP100 does not disconnect even when disabled by remote

I am trying to use a BP100 to disconnect a DC/DC charger from the main battery system.

When the DC/DC charger first starts up, it has a large inrush current that trips the Pylontech battery. I want to use the BP100 to leave the DC/DC charger disconnected until the DC/DC charger has booted up and has begun to output 50V. Once the DC/DC is putting out 50V it does not trip the Pylontech.

What is happening is that, even with the remote jumper removed, the BP100 is still connected and the Pylontech trips out. Victron connect says the BP100 is "disabled by remote", but there is still a connection.

It also seems to be taking the voltage reading from the output instead of the input.

I have tried this in normal, relay and lithium modes.

The DC/DC is connected to the IN and the Pylontech is connected to the OUT

dbx120 asked

0 Answers

How to change the sign for a DC Power from + to - on a system with DC user and DC charging .

How to change the sign for a DC Power from + to - on a system with DC user and DC charging .


Should be negative value because 51W is usage.

This value becomes negative when the Orion charger is on.

robert-larsson asked
cargol66 answered ·

2 Answers

DC Power shows incorrect consumption on unloaded phoenix inverter

After some time wondering why my "DC Power Consumption" some times report incorrect values in the dashboard i started trying to figure out why.

System components:
* Phoenix Inverter 12V 800VA 230V
* Smartshunt 500A
* EPEver PC charge controller (reporting to venus)
* Pi3 with Venus os
* 100Ah 12v Lifepo4 battery

While running on battery and no or a small load on the inverter, the "DC Power" reports a power consumption of approx. 23w or 46w more than that the actual power used displayed on the battery shunt on the Venus and in VRM.

Display when inverter is loaded with approx 12w(bulb) + 6w of inverter idle consumption:


(The shunt reports correct all the time, checked with a clamp meter)

I've seen the difference between shunt and dc power to been up to 46w when the inverter is completely idle(ON but nothing connected on AC side)

After some peeking into `dbus-spy` i think i've found the issue, and it seams to be that the inverter reports between 0 and -0.2A load on `AC/Out/L1/I` when idling, reporting -0,1A on 230v will report to -23w of usage and shown as 42w( -1*(-19+-23) ) extra ont the "DC Power" block in the UI. This is also the reason why the issue disappears when the inverter is loaded, as this negative reading then will be gone.

As for now it looks like the current reading on my inverter could be out of sync inside the device, or that it just displays incorrect values when idling... Is there a way to get this reading "in-sync" again (a form of calibration?) or something else that could be done to make my reading more exact? eg. ignore current readings bellow zero from the inverter ? as the inverter have no way of generating back power there should never be a negative value reported on the AC side.

Anyone have an advice for this issue?

runar-borge asked
rpetrovski-forum answered ·

2 Answers

Cerbo GX Current Consumption

Hi, I am looking for current consumption of Cerbo GX @ 12VDC. For comparison, the Venus GX is listed at 210mA at 12VDC in the manual. Cerbo does not list any power consumption in the manual.

I would like to install on a boat mainly to link my MPPT via Wifi to the VRM website, but am concerned that the current consumption will drain batteries too much. I will be using 2x 50W panels, but would like them to primarily charge the batteries.

pyro asked
jandersb answered ·

12 Answers

MPPT as a DC to DC converter

I have a large battery with a nominal voltage of slightly over 48v. On the solar side, I have 2x MPPT 100/20 and 1x MPPT 150/35, with 48v loads made up of a 48v Phoenix 1200w inverter and a 48v to 12v DC to DC converter buck converter (non-Victron). I have all of the Victron devices monitored via Venus OS

I'm hoping to use a spare SmartSolar MPPT75/15 as a replacement to the DC to DC buck converter, where I would connect the 48v battery to the PV input and use either the load output or battery output of the MPPT75/15 as a 12v power source to my 12vDC system. I have three questions.

  • First, is it better to use the battery output or load output of the MPPT75/15 as the DC output to my 12v system?
  • Second, is there anything I need to configure beyond setting the battery voltage on the MPPT75/15 to 12v in order for this to work and to have Venus OS understand this as a DC to DC converter, not a PV charger?
  • Third, generally, my 12v DC sources draw less than 15 amps; however, given that I already have the buck converter, I plan to wire it in parallel with the MPPT75/15, and have both the input and output connections of the buck converter switched so it will normally be disconnected but can be manually connected in the event of a higher current need. Does anyone see any issues with this setup?

jonathanr asked
jonathanr commented ·

1 Answer

Need help reviewing a compilation of alarms and commands for my Victron system

I've compiled a table of all alarms and commands that are identified in the manuals for my Victron system, which is comprised of two Lithium Smart 12.8 200ah batteries, Lynx Smart BMS, Lynx Distributor, Cerbo running DVCC, Multiplus 3000, two Orion 12/12/30 B2B chargers, and an MPPT 100/50 solar charger.

Would you please review and comment on the attached table? Thank you very much in advance for your kind support.System alarm and isolation table.pdf

David asked

0 Answers


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