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Adding portable solar contro to viktron buss bar.

Portable solar panel controller has positive and negative alligator clamps.

Positive to Battery positive post.

Negative goes to which end of the buss bar please?



larryabela asked
kevgermany answered ·

1 Answer

solar yield and

I'm trying to run an automation through homeassistant, where if the solar yield is big enough to run my pool pump then turn on the pump. Problem is which entity to monitor on victron equipment?

jacques-bands asked
jacques-bands commented ·

1 Answer

Multi RS Solar SOC

Currently I am having to reset the SOC display every couple of days. After a couple of days, it shows about 30% when in storage mode (54.4V), is there a specific method for calibrating this SOC reading so it doesn't need to be reset all the time?

lintech asked
Alexandra commented ·

4 Answers

New blood needs sanity check. - Using Victron MPPT & Battery with Synapse 3.0+ inverter



I am just starting out in he PV / Backup system world and would appreciate it if someone would let me know if my plan for a system upgrade makes sense.


My existing system is made up of a Synapse 3.0+ inverter with two lead-acid batteries in series to provide a small amount of backup power to a fridge, PC and some lights during rolling blackouts. I'm South African and, for someone who doesn't know, we have frequent scheduled blackouts (3 a day for 2h30m lately).

The Problem:

The batteries are now showing signs of corrosion and have lost most of their capacity. Many days there isn't enough time between blackouts for the batteries to recharge fully.

My Goals:

1) I would like to keep the Synapse 3.0+ to charge my batteries from grid at night time after a blackout.

2) I want to replace my worn batteries with Lithium for greater DoD.

3) I want to add PV solar to my installation to allow the new batteries to get at least 1 full charge daily.


My Proposed Solution:

The picture at the top of the post is a simple diagram of the changes I'd like to make to my system.

The first problem I have is that my roof is almost completely East/West facing. This means I need two strings on my roof to get the required coverage during the day to ensure at least 1 full charge per day. My plan at the moment is to have 2x360W (40.4V Voc, 11.4A Isc) panels per string.

Herein lies the second problem: The Synapse 3.0+ only has 1 PV input. This means that I need to get an additional MPPT to run the West string. For this I am looking at the Victron SmartSolar 100/30.

For the battery I am thinking about going either with 2x LFP 12.8/160 or 1x LFP 25.6/200 with the smallBMS for management.

My Question:

Does the diagram make sense as a system that will function as intended? Is there a better design that is maybe cheaper?

Also, I have been told by a supplier that the additional MPPT will only charge the battery and won't provide power to the Inverter, is this right?

Any advice and/or link to a similar functioning design would be greatly appreciated.

atloubser asked
kevgermany answered ·

1 Answer

BMS shutdown and system powered by solar?

I just manually hit the off button on my REC Q BMS. CLANK went the contactor, stuff started beeping for a few seconds, then everything came back online with the battery disconnected. I did not expect that!

This system is a Cerbo GX doing DVCC, REC Q BMS, SmartSolar with VE.can, and a MultiPlus.

So the default is to keep the system powered up from Solar if that’s sufficient for the loads? I’m amazed. Can this be changed?



Adam Sherman asked
klim8skeptic answered ·

1 Answer

Grid Tie inverter with limiter?

Does Victron have a product(s) to do the following:

-Take power from solar panels and feed it back into mains, but try and limit the amount fed back so that a CT measurement is kept as low as possible but never negative (with the idea of putting the CT on grid feed so that no 'excess' over local load is ever fed back into grid).

-Looking for only 1500W or so, no batteries.

secto-kia asked
Tobias Franklin answered ·

3 Answers

Is my solar actually charging anything?

I’m a bit confused by this. We are currently discharging at -136w but our solar is bulk charging at 65w so shouldn’t we be discharging at a rate of 138w (load) - 65w (solar) = 73w discharge?


allswell asked
pwfarnell edited ·

1 Answer

Charge settings for 48V NiFe battery banks

All: Would appreciate your guidance on what you are using and your experience. We have two 48V NiFe battery banks, in parallell, each of 39 NiFe 1000 aH batteries with total capacity of 2150 aH. Would like to know what others are using for bulk, absorption, and float voltages and times on bulk and absorption. We've been told we want to reach 64.35 V charge voltage during the day. Higher or lower? We have 30.7 kV solar panels charging, can use grid or generator charge as well, but we don't given battery inefficiency. What floor on discharge do you set? Thoughts?

wdhaskins asked
mvas answered ·

1 Answer

VRM stats, Solar "To battery" graph


Just checked my stats in VRM portal and on the dashboard in the "Solar" stats it is not showing energy going to the battery. My system is set up as bellow:


My Multiplus-II is using excessive solar power to charge batteries and that is working correctly, but in the stats everything has been counted as "Direct use" :


just a small 0.02kWh has been shown as "To battery" which is wrong. At the time when I took the screen shot, the battery has been charged from 84% to 100% and at the moment excessive solar power is going to the grid which looks like it's been calculated correctly. Any idea why is it not counting "To Battery" energy correctly???

mysik asked
para756 answered ·

3 Answers

DC-DC and solar charger priority

I am looking to buy a Orion Tr Smart DC-DC Charger and a Smart Solar MPPT charge controller for installation in a caravan. Will these work together - if both are able to supply current into the battery, does one have priority or do they both supply simultaneously? I am conscious of the maximum battery input current of 40A. (I have two 100 Ah GEL batteries).

martyhoff asked
martyhoff commented ·

1 Answer

Historical data via API


I am sorry if this question has been answered before, but I can not find anything.

I wonder if there is a way, either via the API or MQTT to get historical data. I don't mind if it is just yesterdays data.

Specifically I want to extract Solar generated and consumption from the day before, so I can build predicted solar from and what actually happened.

I am aware that it is available to download from VRM, but I would like to automate it.

Thank you in advance


tashbee asked
tashbee answered ·

2 Answers

Has anyone had their G99 A1-1 approved in less than 15 hours


I am sorry, I feel as if I am bragging.
But everything I had read about G99 forms was super scary and stressing me out loads.

And I just wanted to share, I followed the guidance found in other threads and submitted my G99 A1-1 form to my DNO, (NG or was WPD) via email at 8:30 pm last night, and at 11:30 this morning I got my approval
Has anyone got theirs back quicker than that ?

it's not that hard or scary, you don't need to pay someone hundreds of pounds to do it for you.
unless you want too.

I am installing a Multiplus II 48/5000/70-50 230V with a 5kW 48V battery and a small solar PV system

Below is the main part of the G99 A1-1 form and my line diagram (a modified version of the one craigc posted)

I also attached the new 31 Mar 2023, G99 test certificate issue 1 amendment 8 (PDF Document - 857 kB) off the Type Test Registery.

It was as simple as that...

HTH, someone



iammotorhomeless asked
iammotorhomeless edited ·

1 Answer

Solar charger shuts down EasySolar-II GX


My system includes a REC Q BMS controlling 8p14s 41kwh batterypack, 12ea 275w solar panels and i EasySolar-II GX 3000/48-32.

During solar charging, expecially during 1500w+ charging and high SOC on batteries, the solar charger shuts down and is no longer visible in VRM interface.

I usually have to Remotely reboot the Easysolar to get it to work. Can then work some hours, or days.

Any ideas?

Regards Stig



stigandresen asked
bladerunnervf answered ·

4 Answers

MPPT and excess solar power

Hi, When the MPPT charger has to limit charging due to the battery (e.g., full battery, absorption stage, float stage, etc), the solar current and power being reported by the app is the "throttled" value rather than what the solar can truly output at that moment. As a result, when looking at the trends or history, when seeing low charging power, it is not possible to know whether it is due to sufficient power that's being throttled vs insufficient charging power (e.g., overcast day, panels too small, etc). I don't know enough about how MPPT chargers work to know how this throttling is done. But it seems it should be possible for the charger to "know" how much energy is being unused when it is throttling the charge, and report it somehow? E.g., as a separate "excess power" band in the history, and as "true solar power/current" in the trends? This would also make it very helpful when sizing up whether a charging setup could potentially support a larger battery.

Antoine asked
Antoine commented ·

2 Answers

0w from mppt solar controller in cold conditions?

My two 410W solar panels and mppt 100/50 controller has been working great. This sunny morning, it is reading 0w eventhough the voltage difference is ok and it says it is in the bulk state. (The cerbo shows the inverter in float state and weare hooked up to 30amp shore power.) However. It was really cold last night and now only 1 degrees C. Is there a problem??? Please help.




ldc asked
snoobler commented ·

2 Answers

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