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Smart Shunt & Battery voltage under load

Hi all,

Busy learning as I go here in load shedding South Africa so any help would be much apricate:)

I will try keep things as simple as possible so here goes:

I have a Gel battery with a 200 ah capacity hooked up to a 1600w pure sine wave inverter. I bought a 500a smart shunt in order to regulate my usage and monitor the vaults.

The question I have regards the voltage reading of the battery dipping substantiality when I apply a load of around 300w. Fully charged I have the battery reading around 13.61v without a power draw exceeding 20w. When the load increases to around 250w the battery takes 30 or so minutes to drop below 12.1 (at which point I cut the load to ensure I don't drain it past dod) just to have the battery jump back up to a range of 12.5v without a load and no charge applied

Am I doing my battery harm by dropping the vaults so low under load?

What is the lowest voltage I should allow under full load?

The vaults have never dropped below 12.3v while no load is being applied? Would it be safe for me to keep using the system under load if I know when i cut the load it returns to thee "safe" operation vaults of the gel battery?

Any help would be appreciated,

Kind regards,


grantiegrant asked
ingo21 commented ·

0 Answers

Etat de charge incorrect

Bonjour tout le monde, j'ai une installation avec deux Smart Solar 250V-85A, un Multiplus II 5 kVA-48VDC_230VAC et 16 batteries lead-acid Rolls 445Ah-6V. Je remarque que quand les controleurs de charge indiquent Float, sur le cerbo GX il est indiqué que le SOC est de 78%.

Pouvz-vous m'aider a trouver une solution ?

Gedeon Paris asked

0 Answers

Battery compartment vent

I'm switching from a four pole diode battery combiner to a Cyrix 12/24 230A. On my previous, very old system, the inputs to the diode combiner also fed two relays. When charging, these would energise and switch on a blower to vent the battery compartment. When not charging, the relays were isolated from the batteries by the diodes.

But with the new setup, the charging sources (mains charger and alternator) directly feed the house and start positive bus bars. Is there an easy workaround or will I need to add diodes again between the charge sources and the two bus bars, in order for the blower relays to energise only when charging?

gil-marshall asked

0 Answers

Equalization on inverter charger

I f I enable equalization on my Victron Inverter charger, after how many days will my batteries be equalizing? I can see there is no pace to set the frequency of equalization.

I can see under equalization the batteries will go up to 17 V.

augo asked
klim8skeptic commented ·

0 Answers

Consumption from the network and not from the batteries at night

I have an Easysolar 24/3000/70-50, the inverter and the CCGX were updated to add ESS, so that it would be powered from the grid when the batteries run out, but at night it is powered from the grid and not from the batteries. Will there be a configuration error? Are the batteries failing? I attach photos at different times.









edurne asked

0 Answers

Centaur charger will not go to float

My Centaur 24/40 charges 12 2V units and has suddenly stopped switching to "Float" and only charges "Bulk" to the maximum of about 28.5V at about 6Amp. Any ideas? Can it be fixed?

@Mattias Lange - DE

vacent24 asked
vacent24 edited ·

0 Answers

Smart MPPT 75/15 load output incorrect power consumption

Hi all,

I have off-grid system powered by 2x160W monocrystale PVs, Smart MPPT 75/15 and (currently) 12V 74Ah Ca/Ca flooded lead-acid battery.

This system powers one WiFi P2P link, and one CCTV.

I noticed that controller shows consumption around 0.2-0.3A all the time, no matter if CCTV IRs are on or off. How it can be possible?

I measured consumption of CCTV with multimeter, and it is 0.16A without IR, while with IR it is about 0.34A

On top of that, there is WiFi P2P link, by I didn't measure its consumption yet.

My expectation of load during the night is 0.5-0.6A, but controller shows 0.2A only.

What am I missing here?



Nenad Strainovic asked
Nenad Strainovic commented ·

0 Answers

Rosen Battery Internal Error

I am getting a random internal error message from Rosen battery, no pattern to it, log into the battery BMS, but no errors present on the BMS, anyone with any experience of this error or help in diagnosing?


neile asked
nickdb commented ·

0 Answers

Premium Lithium Batteries With Victron


Has anyone integrated Premium Lithium ( Brand) Batteries into a Victron system?

Jack asked

0 Answers

12v UPS battery display only unit with phoenix and multiplus range

Hi All,

I'm looking for a solution where one can add a basic display only unit on a 12v battery connected to a phoenix or multiplus inverter/charger

hdp asked

0 Answers

Victron Lead Acid Batteries - Failure ?

All Victron batteries must have a manufacturing error after a lot of test and research on around 300 batteries from Victron mainly super cycle 25AH over 250 and 18 batteries Gel Deep Cycle 220Ah.

Most of the super cycle they fail within 6 months to 1 year even if you have them on float voltage and not cycling them, if cycling them on a solar system best you can get is 6 months. 30% got a catastrophic effect of swelling. Other manufacture of batteries with 4 year floating still there and running without a problem the only difference is that is 18Ah instead of 25Ah.

After 1year of using them new ones with serial numbers came out thinking they fixed the problem but at the end they all failed from 25Ah day one measured with a proper load tester they all end up at 3Ah the ones that are always on float voltage , the ones doing cycles are 100% dead. It was a big loss for us and there is no support or guaranty from our local dealer since they are not replying to our calls. They tried at the beginning to help but that didn't help since there is no response.

The 220Ah at a controlled environment at 25-30 degrees Celsius 70% state of charge as a discharge they get a half capacity if not less on some of them after 1 year.

After 1 year and 2 months it was failing cause of some of the cells in series of the 4 was actually close to 50Ah and some on 119Ah on 2 strings parallel of 4 in series.

All batteries show a good voltage like a new graph but with the difference of the capacity instead of 220Ah there new capacity 120Ah or 50Ah, on the small ones 25Ah when new but after 6 months to 1 year 3Ah if not swelling.

Note that internal resistance was measured but it can’t be trusted since it was showing good on a lot of cases but the capacity was not there, most test where done with C20 and C10 when new even C2 was good.

Hope this 2 year test and research on Victron batteries will help.

What is your experience with the Victron Lead Acid Batteries?

Alexandros asked
Alexandros edited ·

0 Answers

Victron Multiplus 12/1200/50-16,230v - AC Grid feed-in based on Battery Voltage

I would like to be able to feed-in to the AC grid when the battery voltage exceeds a certain voltage (10.0V), the battery has an external charge source and the inverter will maintain this desired battery voltage by feeding the excess energy into the grid. Please advise on how to set this up. I have all the necessary protocol equipment such as the CerboGX modules, MK-USB3 cable, GX Touch, BMV etc but looking for advise on how to configure the inverter for the desired operation. Please advise.

solshare2022 asked

0 Answers

Batteries et rechargement par groupe


Mon questionnement est certainement basique mais je rame encore un peu sur le fonctionnement de mon installation. Ma maison n'est pas reliée au réseau électrique, elle est complètement autonome. Les anciens propriétaires ont fait l'installation photovoltaïque (en 2015/2016?). 2 PV 250w, 2 régulateurs MPPT 100/15, 4 batteries AGM BTL12/200 (qui ont déjà 5 ou 6 ans mais très bien entretenues), un onduleur Multiplus Compact 24v/1200va/25a, et un contrôleur de charge. Au départ, chaque PV était branché sur un régulateur. J'ai rajouté deux PV 280w car la production était trop insuffisante pour les longues périodes nuageuses. Et j'ai aussi un petit groupe électrogène de 2kw. J'ai mis les PV en série branchés par deux à un régulateur par série (les deux anciens sur un régulateur et les deux nouveaux sur l'autre, soit 2×250w et 2×280w). Alors oui, les régulateurs sont sous-dimensionnés pour absorber toute l'énergie produite par les panneaux mais le vendeur des derniers PV m'a dit que ça ne gênait pas le fonctionnement, l'installation n'était simplement pas optimisée. Il me faut redimensionner tout ça mais je n'en suis pas encore là (d'ailleurs tous vos conseils pour dimensionner une installation sont les bienvenus). Et jusqu'ici tout fonctionne. Mais ce weekend, les fusibles des régulateurs m'ont fait faux-bon. L'un a grillé, et l'autre était en partie mal connecté. Je n'ai pas établi la cause, je n'étais pas là ce weekend mais une erreur de manipulation de la part des personnes présentes pourraient bien être l'origine. Toujours est-il que personne ne s'est rendu compte que les fusibles étaient grillés. Les régulateurs n'ont pas rechargés les batteries qui se sont déchargées progressivement (le frigo est branché en permanence) jusqu'à ce que l'onduleur se mette en sécurité pour éviter une décharge profonde. En rentrant dimanche soir, je réalise qu'il n'y a plus de courant, les batteries sont à 10v, je trouve la panne, je règle le problème, je fais tourner le groupe 2h pour recharger un minimum vu qu'il fait nuit et que le frigo va redémarrer. Lundi, pas de soleil, les PV rechargent très peu, le frigo consomme toujours, hier, pas de soleil, les batteries rechargent très peu, le frigo consomme toujours, en rentrant hier soir : pas de courant, onduleur en sécu, les batteries sont aux alentours de 7,5v! Il est trop tard pour démarrer le groupe (j'ai des voisins). Ce matin, nuageux, les PV produisent peu, je démarre le groupe. Maintenant j'essaye de comprendre.

1) Est-ce que lorsque le groupe recharge, les panneaux produisent toujours ? Les deux modes de productions sont-ils en simultanés ou est-ce que le groupe prend le relais et les panneaux "tournent dans le vide"?

2) À partir de tous les éléments de puissance décrits plus hauts, combien de temps dois-je faire tourner le groupe pour recharger les batteries ? Quelqu'un peut-il m'expliquer quel est le calcul ?

3) Les batteries sont descendus à 7,5v, elles ont passé la nuit comme ça (environ 8h). C'est des batteries AGM. Quel impact sur leur durée de vie ? Dois-je envisager de les changer rapidement ? À quel point peuvent-elles supporter ce genre de décharge profonde (sachant que c'est la première fois) ?

Merci pour vos réponses. Je ne suis pas hyper au point sur toute cette technologie mais j'essaie de comprendre et je progresse doucement.

erika-grenouille asked

0 Answers

Phoenix 24/3000 - Erfahrungswerte Batterie-Erneuerung LiFePo

We would like to replace our old AGM batteries (600 Ah) with modern LiFePo batteries in our garden house (6panels, 1.2kWp power, Phoenix 24/3000 and a MPPT 100/50 BlueSolar). Can anyone share their experience / recommendations here? Thanks a lot

offgrid-see asked
offgrid-see commented ·

0 Answers

Low Voltage Alarm goes off earlier and earlier

We have noticed that our voltage drops under 10 so the low voltage alarm goes off. This never happened 2 months ago, but now it is happening more and more. When this problem first occurred, it happened when the battery level was around 20%, but it is coming earlier and earlier. The two last times the low voltage alarm starts when the battery is at 31% , and the voltage seems to be low.

But why does this happen? and why is it coming earlier and earlier?

helgamarie asked
klim8skeptic commented ·

0 Answers

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