BMV Battery Monitor

Thanks in advance for any help

I have a Yacht application. MultiPlus 120, CCGX, BMV702, (6) Firefly AGM Batteries. System has been working flawlessly. We have recently been away for normal Mains / Shore Power connection. Recharging via DC Alternator and Generator / Multi. Now we are back on Shorepower connection.

With Multi / ON and charging and various DC loads ON (dcv Frig, lights, Radio etc..)

The SOC is now declining slowly while the Multi is charging (Float @ 13.4 dcv). Via the CCGX I am seeing a small (-1 amp to -4 amp) load from the Batteries and this "I assume" is causing the SOC to fall.

It appears that the Multi is covering all DC Loads and is maintaining the Batteries but the SOC is fall. I have review the BMV settings

01 BC 660

02 CV 13.2

03 TC 4%

04 CD 3 min.

05 PE 1.07

06 CE 95%

07 CT .1

Remaining set Default

Any suggestions??

Thanks Tom

Hi,

I have a Phoenix Inverter Compact 2kVA which I have been using satisfactorily for over two years and am now wanting to use my BMV-700 to provide auto cut-out to protect the batteries from excessive drain.

The short question is: can I directly wire the BMV-700 relay into the Phoenix remote switch terminals to achieve this or should I use a further external relay between the two?

The longer background to this is … I changed the DIP switches in the Phoenix to select remote switch operation and wired in a simple manual on/off switch to the terminals on the circuit board. Using this manual switch, the system continues to operate as it has done since 2017. When I replace the on/off switch with the BMV-700 relay, the Phoenix starts up ok (with minimal load of just my internet router), but when my fridge is turned on there is a large, prolonged power drain (c. 1kW) from the batteries (as observed on the BMV-700), the inverter fans start up for a couple of seconds and then the inverter auto powers off (the BMV relay remains on). If I revert to the manual switch everything is fine again (there is of course a very brief power surge when the fridge starts, but it settles to the 100W steady state within a second or so and the inverter fans have no need to activate). I have repeated this three times, each time the fridge causes this large power drain with the BMV but there is no problem with the manual switch. This makes no sense to me!

Any help or thoughts appreciated!

My Lead Acid OPzS battery bank is "becoming smaller" as I continue to load the system more an more. Initially I sized the system for 20% DoD, but now in next winter I am afraid it may reach 40 to 50% or even more.

I have now the chance to get a good priced set of Winston LiFePO4 90Ah cells and I was thinking to build a smaller independent system to offload some of the work of the main system.

I allways thought it would be not advisable to put lithium in parallel with lead acid, but the more I think of it, the less crazy it seems. My LA system is 24V based, the 8 cell Winston would be 25.6V nominal. I would source a 3rd party BMS to manage the lithium. Maybe the BMS can take care of the issues - disconnect in low and high side of the daily swings.

I actually have found a product to make hybrid battery banks (BOS - LE300) so maybe this isn't so crazy after all.

To install in parallel and monitor the 2 strings I was thinking if it would be possible to use a separate BMV on each string (Lithium and OPZS). Is this possible, using 2 BMVs on same Venus device?

All- Just purchased some new 6v VMAX 225 batteries (https://www.vmaxtanks.com/V6-225-6Volts-225AH-Deep-Cycle-High-performance-AGM-Battery-_p_48.html ). Two of them in series to obtain 12 volts. Few basic questions:

1) On my battery Monitor (BMV-700) -- When setting the capacity do I set 225 ah or 450 ah? Bit confused because although there are two batteries at 225 ah they are only at 6v vs. 12.

2) On my Victron MPPT 100/50 solar controller -- Is battery type 2 correct on the rotary switch? In addition should I leave the default settings or change them to something custom?

3) Any other setup items on the solar controller or battery monitor I should be looking at?

Thanks all in advance!

I was trying to setup my BMV-712 via bluetooth using an Android phone running VictronConnect. I was able to connect but VictronConnect wanted to update the firmware. It got to 4% and failed with the following message: Result: #6 The product did not activate its bootloader although it should have.

I tried running VictronConnect on a Win 10 computer but it would not find the BMV.

Is there a work around for this?

Hi there I am in the process of retrofitting my sailboat with Victron equipment. The first item being installed is a BMV 712 but will be adding a MPPT and potentially a charger/inverter thereafter. There is the factory charger (will the BMV tell me if it is charging to the correct charge profiles or do I need another device to track the charge profile over time). There is a FET Battery isolator wired to the alternator that combines both start and house banks for charging under motor.

Finally are there any resources to help me put together the wiring diagrams (including the required fuses etc) for adding the Victron equipment to an existing setup?

Thank you!

My BMV 712 smart is set to alarm on high voltage via the battery settings on the unit. On high voltage however, the display flashes and the alarm symbol shows but there is no noise. The buzzer is set to 'On' via battery setting 32. How do I make it so the buzzer sounds?

Hello everyone.

I currently have a BMV-712 installed in my Travel Trailer, and I have upgraded the batteries to a pair of 6V deep cycle golf cart batteries. I am currently using the auxiliary input to sense midpoint voltage of my battery bank.

In the near future I plan to install a SmartSolar 100/30 MPPT charge controller, and I have read that it can read the temperature and I believe voltage from the BMV-712, and adjust it's charge parameters accordingly.

In my case, I only have one possibility, temperature or midpoint voltage as an option. Is it more beneficial to sense temperature or midpoint voltage? Is there a way to sense both, such as the Smart Battery Sense?

Thanks everyone.

Dear Victron and Victron users,

I'm using the Victron Connect App with a Victron Bluetooth dongle to log settings and history of different BMV-700 monitors, but with the new software version (5.8) I'm not able to open files that where saved with an older software version (5.7). Why is the software and the saved data not backwards compatible? how can I open 5.7 data into 5.8 software?

I have a SmartSolar MPPT 7515 talking to a BMV-712 over Bluetooth. In the VictronConnect app, the MPPT says this:

VE.Smart networking

This product is configured for
VE.Smart networking and is
receiving the following data from
the network.

Battery voltage
Battery temperature

Why not SoC, too? I'd like to control the load output based on SoC rather than plain voltage.

They're also both VE.Direct connected to a CCGX, which is getting SoC from the BMV, but apparently not feeding it to the MPPT either.

It occurs to me that I could use the relay on the BMV to drive a load switch, which would accomplish the same thing. But it'd be nice, consider this a feature request, if the MPPT could do it too. (And as others have pointed out, this would allow the MPPT to measure consumption.)

Is it possible to connect a BMV battery monitor to multiple Venus GX units using a USB hub so that they all see the same battery SOC?

Hello community

I wonder what sort of protocol the little Shunt to the BMV700 is using. Simple analogue would make it an easy target for crosstalk and interference, while RS232/485/CAN needs a real uC (or better a DSP) at the shunt. As I have no logic analyzer or Osci available so hard to look into.

Background is the resilence to background EMC "noise" like parallel running big power cable (battery) or switching noise (Smartsolar, Multiplus).

Cheers

Michael

I am installing a lithium battery in my van, using a Redarc dual charger and a Victron BMV-712 monitor. According to the Redarc manual, I need to install a low-voltage disconnect. Does the BMV-712 provide that function, or do I need to install a separate low-voltage disconnect?

I have a BMV-712 that is used to monitor the state of charge of a 100Ah LiFePO4 battery. I can see it measuring the load (e.g. I have a fridge pulling 65W) and the SoC begins to drop from 100%. However, when the load switches off (e.g. the fridge reaching temperature), the BMV-712 returns to 100% - it does not retain the prior value (i.e. 97%). That is, it is not accumulating at all. There is no active charging of the battery at this time.

Has anyone experienced this? Is there a way to fix it? Without this the product is useless.

I have a BMV 702 connected to a battery system. I use the relay (normally energized, closed) to control another relay where all positive loads are connected. When the BMV detects the battery is below 11V the BMV relay is opened and the load relay is open, disconnecting all the loads.

The problem is that in this situation the monitor is consuming 15mA which is a lot. Is there any "clean" way to disconnect the BMV to avoid discharging the battery when the system is not in use? A switch in the positive supply cable? Any other way to achieve the same but but having the relay normally de-energized? Other solutions?

Thank you!

Hey everybody,

how do I know the correct settings for my BMV? Especially:

1. Charged Voltage
2. Tail Current
3. Peukert exponent
4. Current threshold
5. Charge Efficiency Factor

As of now, measurement is completely off (black-out at 95% SOC). They don't drop a single word on their website...

Thanks!

Looking at the Victron diagram for wiring a starter and house battery, here are my questions:

1) I don't need to monitor my starter battery. Can I assume that wiring only my house battery will be the same as wiring the battery designated as the Starter Battery in the diagram?

2) I read that if anything but the shunt cable is attached to neg side of my battery, the 712 will not work. I need to connect a Victron solar controller to the battery. How do I do that if I can't connect to the neg side of my battery? Does the neg on the solar controller connect to the load side of the shunt?

Thanks!

Is it a thermocouple, resistance (PT-100, PT-1000, other) or some other kind of sensor?

In the morning, the BMV-700 indicates a SOC of say 70% with the 200Ah Lithium battery. When the sun comes up, solar charging starts. I have 3 * 120w solar panels charging through a REDARC BCDC1240D charger on a Lithium profile. The strange behavior is that by 8:30am the BMV-700 indicates a SOC of 100%. Now the amps deficit at 70% SOC is about 60ah; with sunrise at 6:30am and a maximum charge of about 20amps, how is that possible? The BMV-700 is all factory defaults except Charge Efficiency is set to 99% and the Peukert's exponent is set to 1.05.

hi, I recently had a new multiplus installation on my boat - I ordered the colour control to go with it but when it was installed they also installed a BMV monitor. I am wondering 1) is there any benefit from having the BMV together with the colour control and 2) are there are potential issues with these 2 units causing problems when wired together?

I have a system that includes the SmartSolar 150/70 networked with a Venus GX and BMV 702. The battery is 24 volts and 258 Ah. The charge controller consistently switches from Bulk to Float seemingly prematurely -- when the BMV indicates that the battery is at around 81-82%.

The battery has a charge limit voltage of 29.2, but I have tried to be conservative with my max voltage setting for the charge controller -- I have it set to 29.0 volts currently. I understand that it shouldn't charge to 100% with that setting (nor do I want it to charge fully out of battery care considerations), but I should think that it ought to charge higher than 80%. Based on the history, I don't see it touching 29 volts even momentarily which might cause the battery to trigger the mppt to change to Float. It seems to get no higher than around 28.8 or so.

Any suggestions? TIA!

System has been installed and working perfectly for about a year now. However, a few weeks ago after the battery bank was fully discharged once, now the bmv will not show any current or load, positive or negative, despite DC or AC draw occurring, or when connected to shore power.

Pic of the BMV showing now draw positive or negative (appliances are on):

[image]

The MPPT shows only a small current coming in. Also, the solar doesnt seem to take in more than 20 watts or so at any given time, even under addition load that I think would call for it. Pic:

[image]

When I turn on a load, like the DC LED lights for example, the voltage on the battery bank drops significantly for a short period. See pic of LED lights turned on and voltage drop for a few seconds:

[image]

When I do the same for a more significant load, like the maxxair fan, the voltage drop is more significant and lasts a bit longer before stabalizing (60-120 seconds).

[image]

Keep in mind no changes to the wiring has occurred, and the system worked perfectly for a year. Could the mppt have gone bad or the BMV or both due to the full discharge cycle that occurred? The batteries are Lithium from Battleborn. Could the surge on the batteries when applying a load indicate damaged batteries?

Thanks in advance

Hi,

i have have a easysolar 24/3000 with 4x 12V/100 Ah AGM Batteries.

Now I added a BMV700 and it has a consumption of 3,7A/100W.

I disconnected everything else from the batteries and its the same consumption.

I also measured the voltage with a multimeter and noticed a voltage loss.

There is no voltage loss wen i disconnect the headunit from the bmv700.

Is the bmv broken?

My potential distributor just informed me, that "the BMV is the basis for a warranty claim for the batteries in the event of a complaint. (No BMV - no guarantee)". Is that true?

The setup:

VICTRON - BlueSolar MPPT 100/50

VICTRON - Lithium SuperPack 12,8V/60Ah

VICTRON - VE.Direct to USB-Interface

VICTRON - Orion DC-DC - 12V->24V 20A

The distributor suggested adding the BMV-712. Unfortunately this is not an option because the system will be used to power an satellite tracking antenna working in 2.4GHz (amateur S-band), so no Bluetooth devices can be present.

Is it possible to turn off Bluetooth on a BMV? Or is there a BMV model which comes without Bluetooth? (It is to avoid a RF interference with an antenna).

Hello,

We have installed the BMV712 with two battery banks and are using the leads supplied with the unit to monitor the voltage of both banks.

We really want to monitor temperature of both battery banks as well. Is there a way to do this without simply buying another BMV712?

Cheers

Al

Hi all,

I've been trying to get something solved as a github issue but I'm not getting much progress so I"m coming to the greater community

Basically I have a MPPT 150-35, BMV-712 and a Raspberry Pie sending stats to VRM

But after months of no issues the BMV-712 stops reporting to VRM sometimes for hours, sometimes for days or weeks as below:

[image]

and

[image]

The only error I can see is in the ve-direct USB logs, an "Tag not found" error as below:

@400000005d50cf190828dc0c 251.526 WRN.VE.Frame: Invalid checksum: 60
@400000005d50cf301a53a59c 274.831 INF.VE.Text: Tag not found: I%�JR$�ʕ56=56
@400000005d50cf301a53c4dc 274.831 INF.VE.Text: CE=0
@400000005d50cf301a53ccac 274.831 INF.VE.Text: SOC=1000
@400000005d50cf301b39f68c 274.846 INF.VE.Text: TTG=-1
@400000005d50cf301b3a062c 274.846 INF.VE.Text: ALARM=OFF
@400000005d50cf301b3a11e4 274.846 INF.VE.Text: RELAY=OFF
@400000005d50cf301c339cb4 274.862 INF.VE.Text: AR=0
@400000005d50cf301c33a86c 274.862 INF.VE.Text: BMV=712 SMART
@400000005d50cf301c33b424 274.863 INF.VE.Text: FW=0401
@400000005d50cf301d2c50ac 274.879 WRN.VE.Frame: Invalid checksum: 41
@400000005d50cf6621c9ba14 328.956 INF.VE.Text: Tag not found: I%�JR$�ʕ0=0
@400000005d50cf6621cb96a4 328.956 INF.VE.Text: H3=-65331
@400000005d50cf6622af8a1c 328.971 INF.VE.Text: H4=4
@400000005d50cf6622b00b04 328.971 INF.VE.Text: H5=0
@400000005d50cf6622b016bc 328.971 INF.VE.Text: H6=-5508856
@400000005d50cf6623a9536c 328.988 INF.VE.Text: H7=5954
@400000005d50cf6623a9d06c 328.988 INF.VE.Text: H8=20478
@400000005d50cf6623a9d83c 328.988 INF.VE.Text: H9=0
@400000005d50cf6623aa4d6c 328.988 INF.VE.Text: H10=15
@400000005d50cf6624a33fe4 329.004 INF.VE.Text: H11=0
@400000005d50cf6624a3bce4 329.004 INF.VE.Text: H12=0
@400000005d50cf6624a3c89c 329.004 INF.VE.Text: H15=27
@400000005d50cf6624a439e4 329.004 INF.VE.Text: H16=21022
@400000005d50cf66259d18d4 329.020 INF.VE.Text: H17=6715
@400000005d50cf66259d9da4 329.020 INF.VE.Text: H18=12082
@400000005d50cf66259da95c 329.020 WRN.VE.Frame: Invalid checksum: 87

When I connect the USB ve-direct cable I see the normal things from dmesg

[ 972.941914] usb 1-1.2: new full-speed USB device number 7 using dwc_otg
[ 973.103615] usb 1-1.2: New USB device found, idVendor=0403, idProduct=6015
[ 973.103627] usb 1-1.2: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[ 973.103634] usb 1-1.2: Product: VE Direct cable
[ 973.103642] usb 1-1.2: Manufacturer: VictronEnergy BV
[ 973.103649] usb 1-1.2: SerialNumber: VE2NHXGJ
[ 973.112960] ftdi_sio 1-1.2:1.0: FTDI USB Serial Device converter detected
[ 973.113158] usb 1-1.2: Detected FT-X
[ 973.114362] usb 1-1.2: FTDI USB Serial Device converter now attached to ttyUSB0

I've also swapped the VE-direct cables between the always working MTTP VRM reporting and BMV-712 with issues and the MTTP always reports but the BMV is always hot and miss

Without knowing why one of the sent tags is invalid I"m having a hard time progressing this issue

I'm not sure from the PIE Venus image if I can capture the USB traffic via USBMON/TCPDUMP ?

Github issues below:

https://github.com/victronenergy/venus/issues/491

https://github.com/victronenergy/venus/issues/500

Any help would be great :-) Thanks Daniel

Hi

I am trying to understand how cold weather will affect the system.

Venus GX
SmartSolar 250/100
BMV-712 Smart
Smart BatteryProtect 48v-100A
2 Pylontech US2000

How will the system behave if cold for the battery to charge or discharge. I assume that the BMS will tell the Venus GX that in turn controls the SmartSolar to stop charging the battery.

So down to my question, will we still be able to run DC loads direct from the SmartSolar that is connected in parallel to the battery (when the sun shines of course) without this conflicting with the battery charge or discharge?

Or will all power from the SmartSolar be stopped?

The display always reads 100% regardless of voltage. One particular instance the voltage: 12.83 volts, current: 15.3A, power: 196W, Consumed Ah: 0Ah, time: Infinite. I've rechecked the wiring and I am at a loss. I do not have Solar on my Travel Trailer. Any help would be appreciated.

Installed new BMV-712 - worked for 5 minutes - until connection via bluetooth - followed instructions to update firmware...to 4.01 - now bricked - displays bt200.....have tried to update via Victron Connect app on iPhone 8 and Mac - same result - Current Version Firmware = none get error #31....HELP