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Pylontech High Voltage Alarm

Hi I'm getting hIgh Voltage warnings on the CCGX. I understand the cells need to internally balance as it's a new system. They are, slowly, day by day.

My issue is that I have set the DVCC to 53.2V to mitigate the alarms and to allow the cells to balance but it's not stoping the alarm!.

Any ideas?

The alarms currently trigger just above 52V.




jimbo asked
jimbo commented ·

2 Answers

Victron SmartSolar MPPT 20A 100V - setup questions

Hi All,

I am relatively new to campervan setups, and I do not have a background in 12v electrics.

I have had a Victron Smart Solar 20A 100V MPPT installed in my campervan together with a new leisure battery, which I am really pleased with on first inspection.

There are a number of options in the Victron Connect app to allow configuration of the Smart Solar 20A 100V MPPT, here are the settings I am talking about.


It looks like most of the settings (Charge Voltages etc.) are set by either selecting a Battery Preset (see options below), or by selecting "expert mode" and specifying your own numbers for the Charge Voltages. The "factory default" seems to be the Gel Victron Deep Discharge option.

The other Battery Preset options available are:



It says in the manual to ensure the settings match your specific leisure battery, and this is where I am struggling - I cannot seem to locate the information needed. The leisure battery installed is a 12V 110AH Xtreme AGM Leisure Battery (XR1750) NCC Class A.

So, my question are:

  1. Are the Factory Default settings ok for my specific battery? Or should I change them?
  2. If I need to change them, then:
    1. Should I pick another pre-set, if so which one?
    2. Or, should I use expert mode and set the Charge Voltages manually? And if I do, what numbers should I use?

A final (less important question) also

  1. What does the "equalisation stuff" do, and do I need to worry about it?

Thanks everyone!

monstreruk asked
tibo-huyers answered ·

2 Answers

Multiplus charging at higher V than in settings

Hi All

My Multiplus, when charging batteries, is charging them at a higher V than in the settings.

For example - if I set the Multiplus to charge in Absorptions 14.6v and float at 13.8v - the BMV712 is showing charging about 0.2v higher - always. When in absorption it is charging at 14.8v and in float it is charging at 14.0v.

Any thoughts on why this is happening ?



miya asked
miya commented ·

1 Answer

Voltage drop under medium load


I have multipluss 12/3000 connected to 2 x 230 Ah victron super cycle in parallel.

System is 3 weeks old. I suddenly noticed a voltage drop 2 weeks ago when someone was testing a vacuümcleaner on inverter. "Only" around 80 amps were drawn for few minutes and the voltage droppen until 11,89 Volts under load. Multipmus gave a short warning by red led status

Batteries were fully charged.

Totday again, batteries fully charged, a small test with watercooker and voltage droppen until 12,2 while taken 109 amps.

Is this normal? Batteries recover immediately after load stops.

Thanks in advance.

Please check date on image.

piet-hein-van-asselen asked
piet-hein-van-asselen commented ·

1 Answer

Permissible volt drop (in a DC bus)

Hello all,

I think I made an expensive mistake

Question 1.

What is the permissible volt drop on the DC side.

In my scenario I have 2 x Multiplus 2 48/5000 in parallel

Our wiring code says that a volt drop (AC) should not exceed 5%

I see that most PV calculators do not recommend more that 3% on DC

Now my dilemma: I am using Two Multiplus 48/5000 in parallel and connected to a common DC bus bar to five Pylontec US5000 batteries

If I use the Victron toolkit calculator @ say max 166A on the bus bar (8000/48) then I can use a 16mm2 DC cable. The DC cable to the inverters from the busbar is 1.7m long as this is under the 3% (closer to 1%)

The Victron rule of thumb (in wiring unlimited) says current/3 which means I should use 50mm2. The example is based on 0.26% volt drop. The Victron table also suggests at 50mm2

Now what? Does this imply that volt drop should not exceed 0.26%?

Although I have Already wired this system, does this imply that I have made an expensive mistake and that I should start again.

Question 2

Another community member also suggested in his post that due to the size of the battery bank (I am using five x Pylontech US5000) that I should take a second parallel cable from the last battery back to the battery Isolator (KETO 160A). This would have been, as he suggested, is to ensure that the batteries charge at the same rate. Would the BMS not take care of this? OR, is this due to the limitation of the actual current carrying capacity of the Pylontech battery cable links.

Question 3

Then, wiring unlimited also recommends that all the DC cables should he the same size, make and length - No problem with that. I am using Two Smartsolar 250/85 and again I determined that the safe DC cable size, also 1.7m long is 16mm2. I also wired as such. Now what to do? Can these remain at 16mm2 or must they increase to 25mm2 / 35mm2 or also 50mm2.

Taking this further, if then indeed the inverter DC cable must be 50mm2, do I then use a 95mm2 from the bus bar to the battery.

Question 4

It is stated that the negative should not be fused in a parallel system. Is this BEFORE or AFTER the bus bar, or not at all? I am using a KETO 160A fused battery disconnector.

Due to the lateness of this discovery - I would appreciate some expert advice as soon as possible. I think my whole problem stemmed from my understanding of permissible volt drop

Many thanks

Lyndsay Cotton asked
David Ferguson answered ·

3 Answers

Multiplus 24/3000/70-50 default low voltage disconnect

Hello, i have a EasySolar 24/3000/70-50 wich basically has a multiplus inside. I use it with a lifepo4 battery. I never run it so low for the inverter to trigger a disconnect, but i'm curious to know what is the default battery low voltage disconnect on the multiplus 24/3000, does anyone know?

Thank you :)

buryck asked
buryck commented ·

1 Answer

Battery Monitor[512], Alarm - High Voltage Alarms - Victron Multiplus and Pylontech Battery

Hi There,

This might be quite elementary to solve, however I keep getting high voltage alarms from the Pylontech battery at times of high solar yield.

What can be done to solve the problem. The alarms tend to show up at voltages below the recommended charge voltage settings, ie max voltage for absorption charging 53.2V and Float 53V in accordance with the manual.

I have downloaded logs for some of the alarm events, these can be found at the following link.


Where could the alarm be triggered and why, and how could the setup/settings be changed to avoid or reduce the alarm event. At present it is a once a week occurrence.

Best Regards


Riaan Barkhuizen asked
Daniël Boekel (Victron Energy Staff) commented ·

2 Answers

Voltage variance between SmartSolar 100/20, BMV712 and multimeter

Hi there,

I am in the middle of setting up my first pieces of Victron gear with my lifepo4 100ah 12v battery.

I love the features and the quality construction but I do have a question.

I am seeing different voltages across my victron gear and readings from a multimeter.

  1. BMV712 reads 13.34v
  2. SmartSolar 100/20 reads 13.33v
  3. Multimeter reads 13.28v

i have taken multimeter readings from various areas. The battery terminals, from the terminal and the shunt and from the mppt terminals. All readings are 13.28v

I have seen comments that there could be an incorrect fuse in the BMV712, but I’m also wondering what could cause this?

I have no long runs of wire and I have checked the crimping on my connectors.

My primary concern is the the mppt charger will stop charging too soon.

Thanks in advance for your help.

corbijn asked
marky01 answered ·

3 Answers

Does the Multiplus act as an autotransformer shore/gen 120v ac input?

I see on the data sheet for the multiplus 24v 3000w inverter/charger that in the "inverter" section it list output as 120VAC +/- 2% and under the "charger" section, the input is 94-140VAC. Does that output apply to inverted loads only, or does it act as an autotransformer and convert (for example) 100VAC shore/gen power up to 120VAC as well? I'm trying to figure out if I should install a separate autotransformer in the RV to account for some RV parks voltage dropping below 110v during periods of high demand. Thanks in advance.

dabean80 asked
dabean80 commented ·

1 Answer

How do I clear a High Voltage alarm on a GCCX from a Lynx Shunt?

I have tried clearing the alarm by going to the GCCX clicking Menu. Selecting notifications. Arrowing down to the alarm. Pressing the space button and pressing the center button on the CCGX.

I have also restarted the GCCX.

According to the VRM logs voltage only went to 14.22, so not sure why that alarmed. Regardless I cannot seem to clear it. Any ideas?


Jon S asked

0 Answers

Cerbo recording high input voltages.

Cerbo recording high input voltages.

Input voltage, MOST of the time, is just below the uk high limit.

When connecting an isolation transformer the input voltage increases a further 7v which triggers high voltage alarm (exceeds the uk limit 253v) at least twice a day.

A week ago, with the isolation transformer connected the input voltage exceeded 270v.

1... With the Victron Inverter upper input limit of 265v, will it shut above that voltage or will it cause damage?

2... The isolation transformer, is not a Victron product. Does the Victron isolation transformer also increase the grid voltage slightly?

Please help.

merlin asked
merlin commented ·

1 Answer

Cerbo has recorded a high voltage input that exceeds the uk limit of 253V

My Cerbo has recorded a high voltage input that exceeds the uk limit of 253V

BS 7671 Appendix 2 section 14.

The UK supply 230 V +10% - 6%

Help on this matter would be greatly appreciated.

merlin asked
Paul B answered ·

1 Answer

Battery Voltage drops when there is no PV power/voltage/Current

The battery voltage drops when there is no available PV power.

Is the battery already faulty/defective?

Battery is a lead-acid AGM.


harry-chavez asked
Guy Stewart (Victron Community Manager) answered ·

1 Answer

Input voltage Mono PERC half cell for the MPPT

Dear all,

I will install a PV system in a very hot and high humidity place in the Amazon region in Colombia. We are planning to use a MONO PERC half cell PV module with Voc= 49,3V (Longi LR4-72HPH-450M). I would like to know if any of you have experience with this type of PV modules in a hot place. My main concern is to damage the MPPT going beyond its maximum voltage input.

If my array has 3 modules in series, I will get 147,9V but I am above the Maximum PV open circuit voltage from the datasheet: 145V start-up and operating maximum. However, knowing that the installation will be in a very hot place, the voltage will drop a bite.

From the configuration spreadsheet, I found that my limit temperature is 20°C. Below it (e.g. 19°C) I will damage the MPPT.


I think that it could be better to have 2 PV modules in series, in order to be completely sure about voltage limits; but I would like to hear from you guys: what do you think/suggest?

Thanks in advance,

marlon-acevedo-rios asked
klim8skeptic commented ·

2 Answers

BMV system Voltage ?


I am setting up a electric drive for my boat.

I have a 72v Motor running of 24 cell LiIePo4 200AH pack with a 24cell BMS system (pack has a nominal voltage of 76.8volts, I want to run this through the Victron BMV . Instructions say max voltage 95v but then in other parts of instructions it says for 12v or 24v systems? Can someone advise if this will be OK or not.

Motor has a 67AMP draw 4500w


deane asked
klim8skeptic commented ·

1 Answer

Battery voltage drop when high load is connected


I have installed the following off-grid system, which has been working pretty good for one year.

  • 4 300W solar panels
  • SMARTSOLAR MPPT 150/35 48V
  • 8 Acid Lead batteries of 6V each (Deka GC15)

However I'm wondering if the behavior I see when I plug a 1200W water heater during the central hours of the day is expected.

As you can see from following graphs the battery voltage drops when load is active and jumps back to an higher value afterwards.

Reading other posts on this subject I've got this is expected indeed, but my question is: do I have to worry about this voltage drop? In other words: should I power on the AC generator if the battery voltage goes down to 46V like in the picture below?

Thanks a lot,




the-salmon asked
the-salmon commented ·

2 Answers

Smartsolar 75/15, Hardcoded Voltages of load output mode "always on"?

Hi Smartsolar- Users :-)

I run a SmartSolar 75/15 together with 12W Solar Panels und a 12V (4S) Winston LiFeYPo 90Ah Battery in my Caravan.

Battery setup is kind of "90% full is enough -Setup" with 14V/13.4V/14.3V/30days balancing. HAve 1,7A Balancer boards on every cell.

Usually, i run the load output in mode "always on" when i use the caravan.

ATM, i am on holiday in Kühlungsborn at the Baltc Sea Coast, where Weather was quite bad. So i only got 130Wh loaded into the Battery the last 4 days, while i used 880 Wh for TV etc., all shown on the Victron Connect app.

Today, i noticed (from my gas warner beeping all the time when getting power, was the only device obn battery power at that time, taks 0,1A) that the load output switched off and on every few seconds. So i checked the battery voltage in the app: as far as i remember, it was at 13,2v.

That is way to early to switch off the battery power; these cells do have ca. 1200 Wh from 4,1V down to 3V/ cell.

Date shown here: https://www.faktor.de/batterien/einzelzellen/winston-lfypo4/lyp090aha-lifeypo4.html

Now, i changed the load output mode to user "defined 2" with off <12V and on >14,4v

I thought "Aways on" would mean" always on? Does anyone know if there are voltage limits in mode "always on"?

Best regards from Germany...


topsan asked
topsan answered ·

1 Answer

BlueSmartCharger IP67 not compensating voltage drop

My IP67 12/25 charger cannot keep a Lithium battery at constant flow/storage voltage. So the battery is permanently discharging and charging again. The problem is varying voltage drop in the chargers wires due to varying DC loads on the boat.

The problem would be solved if the IP67 charger could compensate for voltage drop. Unfortunately sensing battery voltage via VE.smart bluetooth network seems to be currently out of reach, which is disappointing.

My idea to overcome the problem is adding a feature to raise the chargers output voltage as a function of current. On my installation a voltage compensation of 15mV/A would be necessary. It would be great if Victron could add a user configurable setting for compensating voltage drop in mV per A of output current.

rheinskipper asked

0 Answers

Best float voltage and absorption time ("Energy Unlimited book)
  1. good morning, I have read (not all given my difficulties with English ....) the book "energy Unlimited", and I have a couple of questions.
    I live in a camper with a 300 watt PV system, 30 A mppt regulator and 2 service batteries (1 + 1 or in parallel, Agm 100 ah and cheap start battery 100 ah) and an engine battery.
    The AGM is almost 3 years old and 900 cycles and still works almost at 100%, the start battery for the services was replaced after 2 years and 700 cycles with another similar one.
    I think I use them in the best way:
    Absorption at 14.4v and floating at 13.7v, with temperature compensation with sensor on the battery.
    The average working temperature is 25 degrees Celsius in the Canary Islands.
    My Tracer 3210 regulator is great but has an adjustable but fixed absorption time. Default to 120 minutes.
    However, I copy the algorithm of the victronenergy regulators.
    If I discharge the batteries in the evening, for example Vb> 12.6, I set 1 hour of absorption.
    If 12.2 <Vb <12.6, I imposed 2 h of absorption, etc ...
    The average discharge each night is at 12.55 v.
    However, while reading the book, I had some doubts about the float voltage.
    The book says that a 13.8v float for a long time damages the batteries due to excessive gasification ... especially the VRLA batteries.
    My batteries on average float from 12.00 / 13.00 to 17.00 / 18.00 (more time in summer, less time in winter).
    The alternator supplies 14.2 v and I connect it to the service batteries with victronenergy cyrix, almost only at night while traveling or traveling in the rain, for the fridge etc. So it's not a problem.
    In your opinion, what is the best absorption voltage compared to the usage data I have provided?
    For now I have lowered from 13.8 default to 13.65.
    If I took it to 13.2 / 13.4 v would I get some advantages in battery life or some disadvantages?
    Thanks and I apologize for the length.

francesco asked

0 Answers

Easy Solar 24/1600/50 Charge Voltage higher than set

Just fitted this unit to my van with 4 victron 106Ah lead carbon batteries wired for 24V. No solar panels yet, so this is the multiplus compact.

Configuration by dipswitches.

Default charge voltage should be 28.8, but is 29.1. (sw3 and 4 both off) Dropping the setting to the preconfigured 28.2 setting (sw3 on, 4 off) gives a charge voltage of 28.8 not 28.2.

These values from BMV712/smart shunt but checked against 2 separate handheld meters at different points in the system. All concur with very minimal difference.

Trouble is this is causing the batteries to bubble away merrily. Even on float the voltage is too high.

Me or a duff unit?

kevgermany asked
kevgermany commented ·

1 Answer

Phoenix 12/50A (3) Charger Input Voltage

What is allowable input voltage for the Phoenix Smart Charger 12V/50A 3 output version? The images show allowable input of 90-265V printed on the cover of the charger but the technical specs show nominal 230V only. I need this for 120V input if available.

the-gooch asked
the-gooch answered ·

2 Answers

75/15 input voltage incorrect

Hi there. I have been running my 75/15 in my car for over 12months, I have a 250w 36v PV on the roof, and up until last week, it run perfectly, keeping my crank and AUX batteries fully charged. My monitoring system alerted me to the fact my battery (AUX) was almost flat, so I checked out the system and found the PV input was only reading 13v, it should be reading 36v or so. Further investigation just now, shows 36v at the panel, 36v at the cables into the 75/15 when they are unplugged, when they re connected however, it only reads the 13v which I assume to be battery voltage. I am 99.9% sure this PV input reading is always 36v-40v when its daylight, irrespective of that, my batteries went flat.

Anyone offer some advice on what could be wrong here? Should I factory reset my 75/15 or is there another option or something I am missing.


marleekreative asked
marleekreative answered ·

2 Answers

How can I increase the charge voltage of my 48 volt lithium battery?

I have a Smart Solar 150/35 mppt Charging a 48 volt (16 cell) nominal system. At mid day with 52.5 volts indicated on battery voltage and In bulk mode charging I often see low (40w) current input. I am set on battery life for charge algorithm. Bank voltage of 53 volts is only 3.3 volts Per cell. I’d like to get a final charge closer to 55 - 56 volts. Can that be done?

mark-f asked
wkirby commented ·

3 Answers

Help me to understand Voltage drop ( decrease ) while under load vs at rest and state of charge

I was wondering what is the true reading of a AGM battery under a heavy load ( 150 watts)

The manufacture of my battery says the halfway mark is 12.4 volts ( 50% ) When I power on my television, I keep it on until it reaches 12.4 but then the voltage increases back up to 12.65 after it’s turned off

I guess my question would be this- would the 12.4 constitute a true halfway mark when running the television because of voltage decrease under a load ?
Or is it safe to run it lower than 12,4 if it bounces back to 12.65 ?
I have noticed that Victron records the lowest number under a load even after it bounces back up.

dallas asked
spirou commented ·

1 Answer

Victron Solar Charger Controller misreading battery voltage?



I have the 20ah solar charger and a smart bmv monitor. Usually things work at expected - hit float sometime most afternoons around 14.2v and sunrise around 12.3v. However every now and then I'll notice the charge controller reading the battery at float in the morning and not charging all day. Example attached. The BMV reads the actually battery voltage correct. I've reset setting to factory, turned off charger and turned back on via the Bluetooth battery settings, checked wires, and nothing seems to fix the issue (the charge controller reading the batteries at float when they are far from it. Current firmware. Any pointers or ideas?

marcop asked
wkirby commented ·

4 Answers

Positive x Earth voltage low on test

Victron phoenix 12/800 inverter installed on a steel Hull boat

When I test across live and negative I get 220v. When I test live to earth I'm getting 140v and when a load is applied I'm getting 80v.

I have replace the inverter and get the same issue. I have run a negative cable to the Hull and the problem persists. The appliance I want to run requires a good earth to run properly.

Any ideas. Help much appreciated.

innovativeecohomes asked
wkirby answered ·

1 Answer

Voltage fluctuation

Hi, I have a multiplus 24/3000 which has been working fine for about a year. Recently the output voltage has been fluctuating between 240v then dipping to 126v about every 20 seconds for about a half second and there is a very quiet click from the inverter. The input voltage is constant having just measured it at 25.6v. What is happening and how do I fix it?

davidatno5 asked

0 Answers

High voltage on MPPT 75/15 battery output, when BMS closes due to temperature

Dear all,

I try to figure out, if the behaviour I see is per design or not. In my van I have installed a Victron LifePo4, a BMS12/200 and a MPPT75/15 with 2x110W solar panels. Due to the current cold weather conditions (<5°C), the battery and the BMS shutdown the battery charging.

Whenever there is sun available, the voltage on my BMS load and the MPPT battery output increase to ~17V. I assume this is due to the battery shutdown for charging. As soon, as the battery is open (>5°C), the voltage decreases to a normal level.

Is that expected? I thought the MPPT will reduce somehow the voltage when there is no charging in progress.

Why I am asking the question? If put the MPPT battery charging minus on the BMS load pin, where all my other load is also connected to. Now I have ~17V on all my devices, as long as the battery is shutdown. Is my design correct or do I need to change something?

best regards,


fabian-pagel asked
petajoule commented ·

5 Answers

Autotransformer voltage outputs are different

I am having an issue with the Autotransformer output voltages - 114V on L1 and 120V on L2 (with no load)

120V current is supplied by a Quattro 48V / 10000 / 140-100/100 to the 100A Autotransformer. I'm using the AT to provide a split-phase 120/240v supply to the 50A main break panel in my RV

I have wired the AT connections according to the diagram #3 shown on the system schematics page from the Victron website: (https://www.victronenergy.com/upload/documents/AT-3-split-phase-120V-to-120-240V-with-Quattro-120V.pdf)

The Ground Relay in the Quattro is set to ON and is correctly grounding the Neutral to earth.

Here are the voltages I read at the terminals:


The problem I have with this is that the voltage on L1 decreases a lot with load, and when occurs equipment will pull more current to compensate for the lower voltage.

Here is a pic of my RV control panel, showing the disparity in voltage between L1 and L2. Even though there are 2 air conditioners on Line2 it has only dropped 2 volts - Line1 dropped from 114v to 105v. This can't be good.


Questions: 1) - Is this method of wiring correct, and 2) what is causing the voltage discrepancy?


Aug-31: Editing this in an attempt to make the question visible again. I'm thinking of sending this AutoTransformer back to Victron as it is not performing to expectations. I have seen voltages as low as 96 volts on L1, at which point my UPS shuts down my computer, and various other circuits shut down. Not happy...

I'd appreciate a comment from anyone who has had experience with an AutoTransformer.


Pete MacLachlan asked
epuhs answered ·

2 Answers

voltage drops from solar panels once connected to MPPT

Hey guys so I have 3 sunpower e-series solar panels on the roof of my van. They are all ran into a fusebox/combiner which when the fuses are shut sends the power generated from the panels to the mppt 150/35 charge controller. When I test the voltage from the panels on the line side of the fuses I get 72.9 volts for each panel. When I close the fuse completing the circuit to the charge controller and the batteries the voltage drops to 1.9 volts tested at the load side of the fuses and at the pv +/- terminals on the charge controller. I don't get any lights on the controller, and no bluetooth connectivity. I'm not sure what is going on, I have 1 panel on each side of the van on it's own charge controller. I messed up on one and had the pos./neg. wires swapped so I accidentally blew the fuse on the 100/20 charge controller for the drivers side panel, but that passenger side 100/20 controller works fine, I can connect via bluetooth, I have lights on the front everything functions properly. So, my other small controller is bad (need to replace a fuse) but the big controller for the roof panels seems to be drawing the voltage from the panels down a lot. What can cause this?

airborneeyepatch asked
Matthias Lange - DE commented ·

3 Answers

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