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MPPT 30/100 and 50/100 forces Cyrix Li Charge to go into overvoltage error

I have 2 MPPT Smart Solar charger (30/100 and 50/100) together with 3 Orion TR connected on a VE.Bus controlled LiFePo battery in van.

My idea was not to load up to 100% SOC all the time (goal is to charge up to 80%). Therefore I planned to interrupt charging based on SOC measured by a BMV700 and using the built in relais to interrupt the VE-Bus signal to the cyrix Li charge relais.

So far so good, stopping the charging process works fine, BUT ....

the MPPT charger has an ideling voltage on battery out terminals of about 16.2 V when battery is disconnected. Cyrix Li Charge recognize this an overvoltage (more than 16V) and prevent to reconnect chargers to the battery.

Any ideas, how to overcome this situation?

richi1230 asked
richi1230 commented ·

2 Answers

Why MPPT is overcharging

MPPT 75/15 overcharging

It was working all fine for 3+ months but then I saw that it charges the battery in 16v+ range. Few days before that I used the same controller to charge another battery and then switched back to the main battery. I don’t know if that triggered some problems because it was cloudy on those days.

But now, if it’s sunny, it goes to 16v range and always stays in a BULK mode (flashing fast), never going into Absorbtion or Float. I tried disconnecting everything and connecting to another Victron battery and the same thing, as if the charger thinks that the batteries are 24v, but they are 12v. Could that be a problem? I don’t have a dongle to check it out, can’t buy one because shops are closed. Is there anything else I can do to find the cause of the problem or temporarly fix it?

My set up:

2x 120w solar panels connected in series.

MPPt 75/15

130ah battery.

As I said before, it was working perfectly for few months and then suddenly the problem occured. Currently my solution is to disconnect the panels if its a sunny day, but my campervan fridge drains it quite fast. I tried partially covering the panels but strong wind blows anything off the roof…

Thanks for help.

andzei asked
eltgeorg commented ·

5 Answers

Preventing over voltage on MPPT 250-100 Charger


I have a quick question about looking at a temporary solution for a customer. The customer has ordered MPPT RS Chargers, and we are using 6x 455W Panels per String. We have designed a custom solar structure that uses 6x Solar Panels. Currently, there are no MPPT RS Chargers available.

Until the stock is available, I am thinking of buying maybe 3 or 4 MPPT 250-100 Chargers as a temporary solution to get the customer up and running. Obviously, the voltage of 6 panels in series is too high for the 250-100. The Panel VoC is 49.85.

My question is around using 5 Panels in series. The MPPT Calculator shows that at low temperatures, the VoC just exceeds 250 volts (around 260 volts), but at 24 C, we are well within the voltage limits and at full sun the voltage drops down to 172 volts.

When the voltage is fractionally over 250 volts, will the MPPT just give an error and wait for the voltage to drop before coming online, or are we talking about blowing the MPPT Charger at 260 volts?

Is there something I could do temporarily to induce a small voltage drop, as this is a temporary solution? Install an inline resistor maybe? Or multiple contactors driven by a voltage monitor / temperature monitor that only closes the circuit once the voltage is under 250 volts?

If I have 4x 250-100 Chargers, the difference between connecting 4 Panels or 5 Panels in series is nearly 4 kW, which is a significant boost for this temporary solution. If I can use 5 panels instead of a very safe 4 Panels connected in Series, it would be a much better working solution until the RS Chargers are in stock.

Looking forward to any thoughts and feedback. Thank you.

Jonathan asked
Jonathan commented ·

1 Answer

Smart Solar 100/30 over voltage every day

I have a MP100/30 charger. It's set up to charge a LifePO4 battery and despite my charge profile settings (absorption 14.2, float 13.5, absorption duration fixed at zero minutes), I'm seeing 15 volts plus in the history screen every day. Even when the trailer is sitting in the rain on an overcast day. The only thing running is a small 130l compressor fridge. Worried about damaging my 200ah new battery. Any ideas would be appreciated. Images of the settings and history below. Cheers. Stephan



stephanv9 asked
maxs commented ·

3 Answers

SmartSolar MPPT output protection (OVP) against single component (statistical/random) failure

Dear forum,

how is the battery output of the solar charge controller protected against single component failures? My concern is that a single failure can result in a higher output voltage than the programmed charge characteristic. When converting a 100V solar voltage down to 12/24V. Since 12/24V BMS MOSFET blocking voltage is 40V-60V V_DS, a shoot through of the charger will result in a failure of BMS, battery and loads. Major internal components to look on might be:

  1. fail short of the switching transistor in step-down application. Or is an isolated topology used?
  2. micro controller crash/fault. Is an internal/external watchdog stopping the swichting?
  3. Drift or failures in AD-converters, references, or voltage deviders and general failure of the control loop. Is there an independet output OVP?
  4. Some kind of fusebraker/crowbar on the battery side?

Is some FMEA available to proove output OVP function under single fault conditions?

Where do I find MTTF values for victron products?



maxs asked

0 Answers

Reasons for Multiplus Powerpack Failure

Hi all

Recently had a Multiplus 48V / 5000 with a powerpack failure. (indicated by the LED sequence). Unit was used in an off-grid application. No Grid connection. Roughly 5 years old.

Replaced the core and the unit works perfectly again.

I would just like to get your views on what might have caused the Powerpack failure. Overload? , Surge? , age?

Thank you.

Kind regards.

Barend asked
cthonicist commented ·

1 Answer

Victron 3600W Isolation Transformer stepping up voltage???

Hi I wondered if some one could help we are using the victron 3600 to prove our equipment cabinets can work using IT mode. our input voltage into the transformer is 240V and the output is 256V?!?! I was under the impression it was 1:1 ratio so input=output. It is causing our ATS (automatic transfer switch) to persistently switch between A and B feed due o over voltage protection. Can anyone explain why we are having this issue



jameskitching asked
Matthias Lange - DE commented ·

4 Answers

Overvoltage protection between PV Panels and MPPT
What kind of overvoltage protection is recommended between PV Panels on the Roof and MPPT (BlueSolar 250/70-Tr) in the house?

ipirk asked
Alexandra commented ·

2 Answers

System Overcharging

I have a site with a battery going into overvoltage alarm. I have updated all firmware and checked the charging parameters.

It apears that the VENUS GX connected is the one 'dictating" the incorrect charge settings.

System config:

Venux GX FW 2.60 DVCC enabled
Quattro 15kVA FW 476 (was 430 with same issue) with ESS
150/70 Smart MPPT
250/70 Smart MPPT
2 x BlueNova 52V 8kWh (to make 16kWh battery)

Charge absorb settings are set to 56.2V, Float at 55.5V.

When Venus GX is disconnected Charging on all devices stops at 56.2V

The moment VE.Bus is connect to the GX the charging (on Generator) goes up over 60V (battery cuts off at this point). This also happens with the battery comms disconnected.

Any pointers on how to fix this?

kenyon asked
Guy Stewart (Victron Community Manager) commented ·

3 Answers

Overvoltage FeedIn stops working when MaxInverterPower configured to 0?

Short question to answer with yes oer no.

Is this behaviour of my system right or did I messed something up.

OvervoltegeFeedIn works fine when "keep batteries charged" is enabled.

But wehn ESS Mode is set to optimised with batterylive enabled and MaxInverterPower is set to 0, to keep Energy stored in the battery for later usage, overvoltage FeedIn is also disabled and MPPT stops charging the battery.

Regards Felix

felix-vt asked
Alexandra edited ·

1 Answer

Suddenly MPPT 100/30 sending PV voltage to battery but no current

I set up a 12v system in a camper van over a year and a half ago with a 175w solar panel, SmartSolar MPPT 100/30 controller, BMV-712, and a 50ah Battleborn. Ran great with no problems. Two months ago I added another 50ah battery in parallel, ran great with no problems. It has been very hot recently and temps have been getting over 120 F in the van when parked. I started to notice that my vent fan was beeping, but didn't think much of it until my fridge had completely shut off but my lights still worked. I then noticed that the charge history showed my battery's voltage maxing out at over 20v for a week and that that no watts from solar charging were recorded for the previous 5 days.

My charge controller just keeps showing the flashing bulk light indicating "no charge". Even in full sunlight with my panel's vmax coming through, but no current or power according to the charge controller app. Strange thing is that the unregulated panel voltage seems to be making it past the charge controller. If disconnect the panels and charge controller, the battery voltage will eventually stabilize. I am assuming the BMS on my batteries has kicked in to stop charging, but my loads must have been getting the PV voltage direct. Hence the fan beeping and turned off fridge.

Other weird part it that in direct sunlight, my battery monitor will register watts coming in but the charge controller wont and maintains the flashing bulk light. In full sunlight, the BMV will record 21v. I have a breaker between PV panels - charge controller and charge controller - positive bus bar. Testing voltage on both sides of breakers and they seem to be functioning properly. Not sure if high temps could have done this, but my system has functioned without issue for a while prior to this.

Any help would be appreciated.

zachary-green asked

0 Answers

BatteryProtect BP220 OverVoltage activating at 14v instead of 16v

I'm having an issue with multiple BP220s where they disconnect power for just 1-2 seconds and then reconnect.

I have a 12vdc saw, hydraulic pump, and air compressor connected to the output of the BP220. There are 2x 12vdc batteries in parallel on the input side. If the battery voltage is at 13.9vdc or higher and the hydraulic pump is run, the BP220 immediately disconnects the power and then comes back on in a few seconds. There is no error code displayed.

I have tested 3 different BP220s and all have behaved the same way.

If the battery voltage is lower than 13.9vdc, the BP220 does not disconnect power when the hydraulic pump is used.

I've connected a multimeter to the input and output of the BP220 and the voltage does not go above 14vdc or below 12vdc (multimeter set to capture min/max voltage spikes as short as 250us).

I've also changed out the hydraulic pump with the same result.

This is installed in a 2019 Dodge Ram Promaster 3500.

I have an additional 8+ vehicles with this configuration that are not experiencing this problem.

I have re-detected the battery voltage by going to mode d on the BP220, same result.

I'm wondering if the BP220 is detecting a very short spike in voltage above 16vdc (faster than my Fluke multimeter can detect). Or if the BP220 has a bug which causes it to shut off on overvoltage at 14vdc instead of 16vdc. Or is there some other problem I'm missing?

kurt asked
kurt edited ·

0 Answers

I have a MPPT 75/10 producing an output of 16.3 volts ?

I have a MPPT 75/10 connected to 2x40 watt 12v solar panels in parallel, and then to 2 x 12 lead acid batteries. It seemed to be running fine for the last 2 years , but It has just started producing an output of 16.3 volts - why would this have happened ?

james-pask asked
james-pask answered ·

2 Answers

Overload L1 on VE bus system

I often have that alarm cleared about 30s later. Last time yesterday at 18:47, maybe at the starting time of my washing machine, but not sure. Does not alarm me but I woul like to understand! My setup:

- Off grid, 2kWp on my roof + 23kWh lead batteries.

- 2 solar MPPT 150/65, 1 multiplus 24/5000/230

- BMV712, CCGX

Around the time of alert, exact time to be checked I am normally on my local sun time (UT+28m) but VRM may have some other tim:

  • 17:39: -0.40
  • 17:48: -121.00
  • 18:06 -7.07
  • 18:24 -24.90
  • 18:33 -5.90
  • 18:51 -3.60
  • 19:10 -6.7
  • 19:19 -124.60
  • 19:37 -128.00
  • 19:55 -8.10

Any idea?

Lionel SEYDOUX asked
ejrossouw commented ·

3 Answers

Solar overvoltage protection - necessary?


I’m installing solar to charge an existing 12v lead acid battery system, I’ve got 2 panels, a 100/50 smart solar mppt controller and I’m also going to install a smart shunt or BMV 712 smart to monitor the battery state of charge etc... ( the current system doesn’t have any battery monitoring in place)

My question is do I need to be concerned about protecting the batteries from an overvoltage event from the solar charging, or will the charge controller provide protection? I was considering using the ve direct non inverting on/off cable between the shunt/BMV and the charge controller?

Thanks in advance!

willcful asked
kevp answered ·

1 Answer

Smart Solar MPPT 150/45 Error 38 and 39

Hi All,

As topic says having error 38 and 39 come up as soon as the panels are reconnected. Checked wiring, battery voltages, shutdown for 3min both battery and panels removed ve.direct cable. Removed all isolators/relays from system and hooked direct to battery with a test set of breakers.

Has been working perfectly, have had no over voltages or spikes, firmware all up to date. Quattro charges no problem at all from Ac Input 1. Had just performed a battery capacity test aswell so voltage has been taken down quite low 42.8v.

System is 51.2V LifePo4. Quattro 8kVa, Venus GX, MPPT 150/45

Thanks Andrew

andrew-p asked
Daniël Boekel (Victron Energy Staff) answered ·

1 Answer

Venus GX Overvoltage Repair
Hi. My Venus is totally dead. I suspect an over voltage as the battery stopped and the mppt voltage probably increased and supplied the Venus with more than 70V. Can it be repaired?. I have opened up but don't see any visible damage. Thanks

greg-walton asked
greg-walton commented ·

2 Answers

Phoenix sinusmax technology and peak power

We have a Phoenix 3000 and we need to power a compressor of a refrigerator that has high starting currents. In the datasheet you can read that the Phoenix is supported with sinusmax technology but I haven't found clear explanation of how it works. Also the datasheet shows that the peak power of the inverter is 6000 W. But How long this power can be handled by the inverter? There are capacitors inside but how many seconds can be covered?

We need to know how much can we push the inverter before it goes in overload condition.

nicolastenico asked

0 Answers

Overvoltage on AC-out




I have got a 120/240V system comprised by 6x Quattro 5kVA 120V units (3x per leg). This system has been working perfectly for a couple of months however for the last few days, when the generator switches OFF the voltage at the output drops for about 30 seconds and we are getting the alarm "#5 Overvoltage on AC-out"

I have checked the voltages on the input and realised the voltage on L1 was quite high 130V approx. I though that was the problem, however I have fine tuned the generator voltage to be closer to 120V and still having the same issue. According with the Victron documentation, this Error 5 could be related to a wiring issue on one of the slaves but I have checked that and everything seems fine.

VRM Portal ID: 0cae7d24a5a1

Thanks in advance.

tony-towers asked
Daniël Boekel (Victron Energy Staff) commented ·

1 Answer

Damaged inverters - how to prove a 208V system has been connected to a 480V source?


We are having an issue with a customer. he rented a 208V-3ph unit from us and when the onsite technician hooked up the generator, he said the inverters blew up instantaneously and there was been some spoke going out of the unit from what they have told us. This is a unit with 6x Quattro 5kVA 120V inverters

The technician on site insist that the generator was switched to 240V 3Ph but I really suspect the generator was set up to 480V and that is why the inverters blew instantaneously. We do not want to start a fight with the client as it is potentially a big customer for us but we need to be able to prove that the fault is on their side. there is no alarm on the VRM unfortunately. My questions are:

- If a 208V unit is hooked to a 240V generator, can the inverters blow up?

- In case that doesn’t and the generator was switched to 480V, Is there any specific component that will only blow up at 480V that can prove this?

I will really appreciate some help on this. We have got 6 inverters damaged and this is an important client that we do not want a fight with but we want to prove them that this was due to a negligence


Jesus Mazo asked
Daniël Boekel (Victron Energy Staff) commented ·

1 Answer

Pylontech U3000 Overvoltage alarm at 89% SOC

Good day

I think this is quite a common point of discussion, but I need just need some confirmation that I understand correctly.

This installation is as follows:

  • 2 x Multiplus II 5kva 48V units set up in single phase parallel
  • CCGX unit
  • 4x Pylontech US3000 modules
  • No solar array installed as yet, purely back-up.

Setup and settings done exactly as per https://www.victronenergy.com/live/battery_compatibility:pylontech_phantom

System was commissioned today and seems to function normally, except for a "Battery monitor (512)- High voltage" alarm.

Battery is at 89% SOC with voltage at 51.81V

Batteries were reasonably discharged (66% SOC) when turning on the system for the first time, so it stands to reason that they might have been standing for quite some time before we received them.

Am I correct in saying that this is a cell balancing issue, and should self-rectify? Or is there something I am missing?

Thank you in advance





botessj asked
botessj commented ·

4 Answers

Generator issue with ESS

Okay so i have a honda eu7000is attached to ac1 on my quattro for backup power. i have dynamic power checked and limit input current to 10 amps. If i have the quattro disconnected from my gx device with ESS it connects fine to the generator. But when i have the quattro connected to the gx controller the generator overloads. I believe this is due to a problem with my generator as it is producing 254V at idle and the inverter is set to 245. Am i correct or is there something i am missing with the ESS assistant setup? or with the color control GX setup?

shayner asked
shayner commented ·

1 Answer

I overloaded 12/800 it alarmed. I reset, then did it again. No lights now. Internal big fuse is unbroken.

I tried resetting a few times. I charged batteries for not very long and reset. I will check in engine bay for breaker and check fuse, not done yet. But wondering if anyone has any other suggestions? Many thanks

annabanana asked
Daniël Boekel (Victron Energy Staff) answered ·

1 Answer

AC-coupled Fronius trips out 3 parallel MPii's off-grid

14.4kWh Lithium

3 x MPii's in parallel set up using VE-Config3

Venus GX sees the Fronius via local link

Fronius Primo 5.0 set to country MG50

Primo ramps up to 2.5kW, batts are at 99%, MPiis then trip on overvoltage

I am measuring the microgrid AC frequency - I do not see it change from 50.00Hz during ramp up

I notice there is no mention in the Victron guides of setting any frequency set points in the Primo

I do know that the Primo can track a changing load via frequency/power control seamlessly/effortlessly as I have seen it done with an off-grid Tesla, via frequency control *only* (ie no data cable)

Is there a Victron ref for frequency settings that should be in the Primo?

I am very happy to change these - we do it with the Volt/Watt response for on-grid all the time.

I ASSUME - that I would set the zero-point in the Primo for (say) 51.5Hz

Please confirm or advise of any other refs?

Thanks ChrisH

chrish asked
chrish commented ·

2 Answers

EasySolar 48/5000 isolates the solar input (Err #38)


I am new to Victron. I have installed the EasySolar in an off grid setup with 9.6KWh batteries (4 x 12V 200AH LiFePO4 - Non Victron - Built in BMS) and upgraded all the firmware.

I have 5 panels in series delivering just under 110V when disconnected and about 10A in short circuit.

When I connect the panels to the unit it doesn't charge the batteries. It issues error #38 input shutdown due to battery over-voltage. I then have to go through the process of resetting the unit.

Any help with this would be appreciated.



mahmm asked
mahmm answered ·

5 Answers

Quattro AC output over voltage when peak loads turn off

Hi, i have a setup where it was wanted to adjust ac voltage up.
(From 230 volt, up to 240 volt.)(3 phase quattro 10k and quattro 15k setup)

but when do, we now and then after peak loads get ve bus error #5, high voltage error.

Can it be that the ve configure settings allow up to 245volt is not fully implemented in alarm Limits in firmware?

We did not see this error before we adjusted the volt output.

and VE configure says ok up to 245 volt.
this maybe would need a new firmware?

Rune Eilertsen asked
Rune Eilertsen commented ·

1 Answer

Controller damage if the battery is disconnected but PV is not?


I have two SmartSolar MPPT 100/20s that I am planning to install. The Battery is 12V 4S LiFePO4. I would like to use a BMS to disconnect charge sources if the BMS detects an over-voltage on one of the four battery cells. If the battery-side of the controller circuit is interuppted by the BMS, but the Solar PV circuit is intact, will the controller suffer damage?

I could add two relays, one to each controller, to also interupt the PV circuits at the same time. However, I am wondering if this is really necessary?



kimsails asked
kimsails commented ·

2 Answers

Centaur 24/80 overcharging at 29.6V HELP!

Greetings to all.

I have on board a Victron Centaur 24v/80A charger charging a bank of 2x2 12V/225Ah lead acid batteries. Recently the batteries started to heat and loose water, when I went to diagnose I found out that the charger is outputting 29.8V regardless of dip switch setting. I found that there is a potentiometer inside and tried adjusting that but I could only reduce the voltage to 29.6V with strange pulsing noise from internal SMPS like it is running on minimum pulsing. I cannot leave the charger like this,it will destroy the batteries. Did someone encounter a similar problem? Is there a solution or should I just buy another charger? This one is about 4yrs old so if its gone already I think I will consider another brand. The one I replaced lasted over 12 yrs. Oh,I tried replacing the batteries with another bank new batteries but the charger is still outputting 29.6V.

bmwmilos asked
philbertoni answered ·

5 Answers

BlueSolar 75/15 load voltage swings with >1amp load

Hi All

Been in contact with the place I bought my BlueSolar 75/15 and Bluetooth dongle and want to hear if someone experienced similar

Its installed in a 4x4 with 100+80w solar panels in series (lots of cloudy days in scotland) It feeds a 12v 90ah deep.cycle battery which mainly runs LED lights and a fridge. Battery is connected to started battery via a Victron Cyrix battery combiner.

Been working well for 2 years and then other day noticed when turning rear LED worklight an approx 1amp load the light output is low and constantly fluctuating. Measured load terminals on the Charge controller and it swings from 5 to 11 volts. The battery voltage is stable at 12.50v at same time. Day was sunny and 34v from the panels and charging state float. When turning on more lights the load voltage drops to 0v and at somepoint it came up with battery overvoltage 23v alarm. Switched loads off and voltage dropped slowly to approx 12v. When disconnecting solar panels and in evenings the unit turns fully off, no light in diodes and not visible via bluetooth

When the engine is running and battery combiner is active both batteries are 14.2 volts. Battery terminal of charge controller is stable at 14.2v Thou when load above 1Amp is applied the same voltage fluctuation in the victron app occurs and lights goes dim and bright randomly

Tried disconnecting the main battery and no change in behaviour. Tried another LED light with approx 1.5amp load and same story.

Is it a faulty unit or is there something else that needs to be looked at? The battery overvoltage error really puzzles me as no changes to wiring and then appears normal again.



usinworld asked
markvanloon commented ·

1 Answer

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