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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

High grid voltage disconnect with Multiplus II in AU, why?

Lets be clear, I understand that power generators should not feed in energy if the grid voltage is already high, hence the regulations around handling high voltages. Hence the locked-in grid parameters.

I have recently has "grid lost" for short periods in the middle of the day when high voltages were sustained. Circuits upstream of the inverter were not affected by a power loss - that made it was clear that the MP2 disconnected itself from the grid. The MP2 went into "Inverting" mode.

The question is "why disconnect from the grid?". Why does the MP2 not simply go into "pass-thru" mode or a "zero-export" mode? To me this seems much more sensible. It achieves the desired outcome of removing the generator from the grid while not drawing down on batteries needlessly.

Is there any way to change this behavior in response to high (10 min moving average) voltages? (yes, ideally, fix the voltage issues but ...)

thank you,


rrroonn asked
rrroonn answered ·

2 Answers

Functional purpose of voltage sense wires?

Can someone shed some light on the intended functional purpose of the Voltage Sense wires on a Multi/Quattro?

Are you using it? If so, how/why?

The manual says loosely that it's "to make up for voltage losses across the wires".

With the volt sense wires connected or not connected, under minimal load or loads in excess of 100A, I've never seen any change in the reported voltage by the system.

This was true even before my installation of a BMV (with the lithium batts) and still so now, since SOC and voltage readings (I assume) are now coming exclusively from the BMV.

The voltage reported (by the BMV) is within .01 V of the voltage reported by the BMS on the batteries with minimal load, and within the expected 2-3% difference under heavy loads.

I'm using 2/0 (70ish mm cross section) wires and runs are around 10-13 ft to the batteries. The BMV is 5-7 ft to the shunt. 24V lithium system.

The lead-acid system prior was considerably sloppier, although still using 2/0 cable, and I still recall no differences.

geomz asked
rjoustra answered ·

3 Answers

Voltage Sense in Multiplus when open


What is supposed to be the voltage in the V Sense terminals of a Multiplus 3000/24/70 when a is connected to battery and operating? The V Sense terminals are not connected (left open) and I see the same exact voltage as in the DC input terminals. Is this normal?

elimac asked
lemonjelly commented ·

1 Answer

Usb low voltage problem - Bluesolar Pwm

Hello I have solar panel connected to car battery through Pwm, everything works fine, but after I started engine with a bit low battery, on Pwm started blinking U 0.2v, which means voltage on usb output is only 0.2 volts. Normally it shows around 5 volts. It happened me once before and after a while it went back to normal, but now it always stays the same.

Pwm is working normally, only usb is not working.

I haven't found any relevant info on this, do you have any idea what can be causing this and how can it be restored?

P.S: I tried disconnecting the module, but didn't help.

Thank you


kubick asked
kubick edited ·

0 Answers

Victron SmartSolar MPPT 150/85-MC4 Not showing panel voltages.

New out of the box. I connected 5 panels in series to the controller. Zero volts show up. Then I connected 1 panel to the controller. Measuring voltage across the MC4 connector is 21.0V as soon as I plug it in? Zero volts. Help?

thesniper asked
Trina answered ·

2 Answers

Voltage and Temp monitor options

What’s the order of preference for voltage and temp monitoring? I just finished setting up my Victron solar generator for my off-grid cabin which is inclusive of a multi-plus 3000, Solar charger 100/30, BVM-712 and Cerbo GX. I have everything set up and working and trying to optimize my settings and limits but unsure which devices is best to handle monitoring or if the Cerbo GX is sharing it all either way.

Technically three of the devices are capable of the temp and voltage monitoring so should I just use one for each function or tie everything to the Cerbo since it will act as the hub? Or should I try to get each device to read as much data as possible?

An example is the temp compensation. The Multiplus has this input along with the BVM and Cerbo but since multi will charge battery when generator is running I assume it’s better to have multi manage directly. I’m hoping that the info is shared with MPPT for compensation as well through the Cerbo.

The multi also can measure voltage at the battery and compensate but then seems to make the BVM midpoint measure redundant. I only have 2 batteries in series so there isn’t much of a midpoint.

Perhaps I’m overthinking it but wanted to see if anyone else had similar thoughts.

bob-cook asked
bob-cook commented ·

1 Answer

What is the Multiplus output voltage?

Hi all, my first post here.

Does anyone know how to calculate the output Voltage of Multipluss II inverter?

For example, the Voltage at the property (distribution board) is exactly 230V.

If Inverter would be charging batteries from the grid then there would be some voltage drop dependng on cabeling and load, say 2%, so Voltage at the end of the circuit where inverter is connected would be 230-230*0.02=225.4V

If now we wanted to export the energy from the battery, we would have to have higher voltage at the property than on the grid side (>230V) so the output Voltage should be at least 230V + whatever voltage drop (lets say we export the same power and it is again 2%). Would that mean that Voltage at output terminals of inverter would be 230+230*0.02=234.6V? Or that plus X% or X Volts ?

Basicaly I am trying to understand how inverter decides what voltage to output when outputing AC current - is it matching the grid+X% by consistantly monitoring voltage at the terminals and making sure that generated Voltage is higher?


r2000 asked
warwick commented ·

1 Answer

BMV-712 firmware issiue?


the BMV 712, BMS 12/200 and Li-Battery is installed in a trailer.
Input (AB) fuse is 15A.

I'm trying to measure the starter battery voltage. The ground is connected through the BMS (AB) and the shunt (secondary input) is connected to the starter battery .

Is this a firmware bug or isn't it possible to measure the voltage across the BMS, because of the diode reverse current protection? Primary battery measuemend is fine.

The discrepancy is exactly 12V (24,4-12,4 = 12V), that looks a bit like a firmware issiue.








heidi asked
heidi edited ·

2 Answers

Controler doesn't read panel voltage

This worked all last season. No changes have been made since. Now the controler doesn't read the panel voltage correctly.

The voltmeter gives me 58v all the way to where the wires connect to controler. As soon as I connect, the voltage drops to 11v and no charging occurs.

I've redone connections with no help. About ideas?



bscholz asked
maxxpwr answered ·

1 Answer

Venus gx VRM portal battery voltage data
Hey everyone,

I’m looking to get battery voltage data as a data point on the vrm portal, I can see the information on the 1hr chart but not on the daily or weekly information it only shows me battery capacity %age

as the BMV 712 only really give you an estimate battery capacity I like being able to look at battery voltage as data point as a fail safe. How could I make this happen? This is what I want to to see but across all points of time history.

Thanks in advance x

Ben Johnson asked
Alexandra commented ·

0 Answers

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