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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

using MPPT solar inverter DC input with an AC generator


I have a question regarding the possibility of using an AC generator with an MPPT solar inverter.

So basically I have a wind power turbine, the generator is a 3 phases permanent magnet synchrone generator.

In order to have a DC voltage, I will use a diode bridge with a DC/DC converter to meet the requirement of DC input of the inverter.

Lets say I will use the Victron EasySolar-II GX (who handle a DC input between 38V - 66V) without battery, and I'm able with the diode bridge and the DC/DC converter to convert the voltage of the AC generator to a DC voltage that oscillate between 38V - 66V. Will the inverter be able to generate power and behave normally ?

I want to know too how the MPPT will work under those circumstances. Feel free to correct me if I'm mistaken, from what I understood, the MPPT algorithme changes the value of the voltage on the DC input in order to find and drag maximum power. In the system that I explained above, the source imposes the voltage I believe, how the MPPT algorithm will be able to find the maximum power point?

Feel free to ask more questions if I misexplain something.

Thanks in advance


cydrox asked
cydrox commented ·

1 Answer

HIGH DC RIPPLE - 3x Quattro 48/10000/140 - 56x US3000C Pylontech

Hello: System Description · Connection Type Grid Connect / Stand Alone · Voltage 440 Volts / 3 Phases / 4 Wires · Project Location - Cuautla Morelos Mexico. Equipment: · SFV - 80 Trina Solar Brand Panels of 505 Watts, distributed in 5 chains of 16 Panels each. · Smart Solar - 5 Units Model MPPT 250 / 100 Tr VE Can · DC Bus Bar - 5 Units Model lynx Power in 1000 · Victron Inverter - 3 units Model Quattro 48 Volts / 10000VA / 140 Amp · Cerbo GX 1 Unit. · Pylontech batteries - 56 units Model US3000C, grouped into 4 groups each with 14 batteries. · Ethernet Switch - Pylontech HUB 1 Unit. Use Case: The main function of the system is to power 24 extractors of 1 HP (750 Watts) 1.6 amp with an F.P. 0.71. Extractors always on 3 from 7:00 am to 5:00 pm. On average, 12 extractors are switched on throughout the day for periods of up to 4 hours. These devices turn on by means of a thermostat calibrated at 30 ° C Background: System running smoothly for 7 months. Preliminary Testing/Equipment Review: · We checked voltage in the direct current terminals with the battery off to rule out current leakage. · Check fuses in the DC bus bar. · Review in DC and AC wiring. · Preventive maintenance to the exhaust fans to reduce the start peak. · Testing of RJ 485 Ethernet cabling between master and slave batteries. · Scanning with Battery View Software · Continuity and grounding tests of AC and DC wiring. Current Failure: After replacing these cards and configuring the system with the EV. Bus (Firmware V497) and the configuration of the ESS or the electrical parameters is the same as in the manuals of Victron or Pylontech, in the case of the Victron Connect you have the (Firmware V2.41). Recurrent alarms or failures: · When we do the process only of turning on and synchronizing the batteries we have an alarm in the VRM High discharge current sometimes with values of 0.0Amp. and others with values of -0.3 Amp. We delete the alarm and continue with the boot process. · Then we turn on inverters, switches of the 5 strings of solar panels and it gives us the alarm of High DC ripple. We delete the alarm and continue with the boot process. · We put the 3 or 7 extractors and take a load of 12 Amp with an instantaneous peak of up to 20 Amp. So the system continues to operate. · Sometimes we have up to 14 extractors on for 1 or 2 hours and it does not give problem or alarm, but sometimes during the operation High DC ripple alarms are presented and the system remains stable but if this alarm is repeated 3 times in a row in a period of 20 minutes the system turns off and gives the High Dc ripple fault accompanied by Inverter overload on L3. · When this happens the system is not reset since the current peak can reach up to 60 Amp. So we chose to turn off the system and turn on the extractors manually one by one. But the failure continues to present itself as if it were a cycle. Has anyone had this problem with DC Ripple? the system was working with the same parameters without this failure.

ruben-velazquez asked

0 Answers

How to charge canopy battery when car is running by alternator and at the same time charge with my solar panels?

I have a redarc bcdc 50a charger and want to use it to charge my 280ah lithium battery when driving and add a solar blanket when stopped. I also have 2 x 170w solar panels on my ute canopy and a mppt 100/20 victron. How can i set my system up so my battery is charged simultaneously when driving by both redarc and victron mppt?

jackormark-82 asked
Kevin Windrem 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
hummingbear commented ·

2 Answers

SmartSolar MPPT 75/15 Load Output Settings

I will be utilizing the load output on my SmartSolar MPPT 75/15s (3 of them for different arrays). All my loads will be 12v DC. Do I just set the output at 12v or do I need to calculate for voltage drop through the bus/wire?

adrianp105 asked
adrianp105 commented ·

1 Answer

DC loads/DC system in ESS


I have a 3-phase system 3x5kVA MPII, 1xMPPT, 2xFronius Symo, BMZ lion battery 48V with BMS, everything is controlled by Cerbo + ESS assistant. Everything has current FW, AC Coupled feed in excess - ON, DC Coupled feed in excess - OFF. Now I canceled home UPS APC (for home server, CCTV...) installed Phoenix inverter and SmartShunt. I turned it on in Settings - System - Has DC system ON. I set the SmartShunt as DC Loads. Unfortunately, I have two problems.

The first problem - the DC loads field does not appear on the display. It only appears immediately after a restart, or on the display that I'm not using.

Normal view ( No icon DC Power displayed ):


Display after restart Cerbo: (as soon as ESS assistant starts, the DC loads field disappears)


Another screen I don't use, here is the DC loas to see:


Would it be possible to modify the FW to show the DC load on the "primary" screen like here?


The second problem - if the battery is charged, CCL 0A. When I turn on the DC load, the battery discharges and micro-cycles (100% -> 97% -> 100%...). Unfortunately, the MPPT does not supply any power (to balance the draw from the battery), the Symo supplies power to the grid. Is this normal behavior? Shouldn't the MMPT regulator supply the same power as the Phoenix draws so that the battery is not constantly being discharged and charged? It can be seen in the pictures above.

Thank you for the responses, or for the advice.


ondra asked
janr-1 answered ·

1 Answer

MPPT Output Under Load

I've noticed that many times when it's nice and sunny and the batteries are fully charged if I turn on a heavy load the 100/30 MPPT won't provide any current from the solar panel until the batteries are significantly discharged, sometimes not even then. Sometimes it will only start providing current the next day. Why doesn't the MPPT always respond to load on the system by outputing current form the solar panel?

robert-barnesi asked
mihaitaiosub edited ·

2 Answers

Phoenix 12/50 Missing in the manual...

Hey there,

I'm new to being a boat owner and therefore to the charger I bought with that boat. It's a good charger i hear because it's a Victron energy charger. Now the thing is, I am not a complete novice when it comes to electricity and so I noticed whoever did the electrical system in my boat, did not do a very meticulous job. I am going to do a better job.
So I read the manual of my charger and I am left with a few questions. Some because I've not been working with DC very much. I cannot find the answers in the manual at this moment.

1. The trickle charge to starter battery is not being used at the moment. There is not much information on the trickle charge circuit in the manual. What type of cable is advised over a two meter distance?
2. I assume, but I don't like that because assumption is known to be the mother of let's say, very big mistakes, the trickle charge circuit is also controlled by the microprocessor and will be able to keep the starter battery charged over a long period of time without overcharging it. Is that correct?
3. The manual says the full charging current is 'divided in two main outputs'. Does that mean I can use both outputs on one battery, as I have only one? I don't seem to be able to remove an output cable without breaking the factory standard.
4. At this moment the 'voltage sense' circuit is not connected, yet the charger moves from bulk, to absorption, to float. Is there any good reason, and I assume there is, to finally start using that circuitry?
5. The temperature sense circuit is not in use. The manual says a sensor comes with every charger. Yet I find no sensor. Looking at the connection diagram, I assume the mentioned sensor is on the board. So just to be sure, is there a separate device that is the temperature sensor? And what type of cable should I use?

Many thanks to anyone who can help me improve the electricity on my new classic second hand boat.

Thomas Tchong asked
klim8skeptic answered ·

1 Answer

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
rikhf edited ·

7 Answers

Strange DC Power Values

Hi All

New yacht install - all new kit. In process of commissioning.

System -> 4x 330Ah Start Lithium, connect in parallel to Lynx Distributor, connected to Lynx Smart BMS, connected to Distributor on other side. Cerbo GX and Touch 70. No loads, no charging devices attached the the final distributor.

This is what the GX Touch is showing - and it looks normal.


This looks as I would expect to see, battery showing -0.4A and -5W and the DC Power showing 5W - which is about right for the consumption of the BMS, Cerbo and Touch 70. So... all good so far.

I have then attached a Victron Smart Charger 5A - to the distributor on right of BMS - to slowly charge the batteries, very slowly for the first time and balance them.

I see this...


Prefect - the DC Power is now showing -59W as power is going in to batteries.

Next - I have disconnect the small 5A charger and have attached the new Multiplus II for the first time, Connected to the distributor on the right of the BMS. Connected VE.Bus and +ve and -ve DC wires only. No AC connections made at all. Not connected to mains AC and no AC loads connected.

When doing this I would expect to see the DC power be shown as a load. I would expect it to be about 5W for BMS, Cerbo and Touch.

This is where it gets strange....


DC power has changed to a -VE number - suggesting is is being charged with 6W. The AC loads look normal - 16W for the Multiplus - inverting - but idle.

Can anyone suggest / explain what is happening here ?

Kind regards, Tim

miya asked
miya commented ·

2 Answers

Looking to add 3 lithium batteries to my lead acid system. One or two dc-dc chargers?

Hello I currently have a set of lead acids charged by solar panels. Im trying to add in a set of lithiums to the array. Does anyone know if dc-dc chargers only work one way? Or perhaps I need two? The idea is to have two different chemistries and be able to charge and use them at the same time without needing to switch manually.

burgboy asked
kevgermany answered ·

2 Answers


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