Victron VenusOS driver for serial connected BMS - JBD / Daly / ANT / JKBMS / Heltec / Renogy / Tian / ECS
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Louisvdw
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A new version v0.6 has been released.
It includes support for the ANT bms & MNB bms.
It also add units to all values and remaining Ah capacity if the battery supports it.
It includes support for the ANT bms & MNB bms.
It also add units to all values and remaining Ah capacity if the battery supports it.
K8MEJ
Owner, Off-Grid Power Systems
Hi Louisvdw. Do you support multiple JBD BMS instances yet? I have four separate 12v batteries running the Overkill Solar BMS (JBD) that I'm eager to connect to my Cerbo GX. Thanks for your work on this project!
tobintin
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Hi Team,
Great works you have here.
I have JBD 8s 200A BMS, EVE 280AH, Lynx shunt VE.Can and a Cerbo/Venus OS on raspberry. I am a noob here and will appreciate a video on how to get my BMS to talk to the Victron system with the set-up for RS485.
Is it plug and play?
Great works you have here.
I have JBD 8s 200A BMS, EVE 280AH, Lynx shunt VE.Can and a Cerbo/Venus OS on raspberry. I am a noob here and will appreciate a video on how to get my BMS to talk to the Victron system with the set-up for RS485.
Is it plug and play?
Louisvdw
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Yes I have made it pretty easy. Plug and play if you use the flash drive auto installer.
I assume you have the USB-RS485 box that comes with the BMS? Plug that in to the Cerbo in a USB port.
Then you download the latest release, put in on a flash driver, plug the flash drive into the Cerbo's USB as well and follow the prompts. It should pick up on it's own.
See all the details on the wiki
github.com
I assume you have the USB-RS485 box that comes with the BMS? Plug that in to the Cerbo in a USB port.
Then you download the latest release, put in on a flash driver, plug the flash drive into the Cerbo's USB as well and follow the prompts. It should pick up on it's own.
See all the details on the wiki
GitHub - Louisvdw/dbus-serialbattery: Battery Monitor driver for serial battery in VenusOS GX systems
Battery Monitor driver for serial battery in VenusOS GX systems - Louisvdw/dbus-serialbattery
github.com
tobintin
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Hi Louisvdw,Yes I have made it pretty easy. Plug and play if you use the flash drive auto installer.
I assume you have the USB-RS485 box that comes with the BMS? Plug that in to the Cerbo in a USB port.
Then you download the latest release, put in on a flash driver, plug the flash drive into the Cerbo's USB as well and follow the prompts. It should pick up on it's own.
See all the details on the wiki
GitHub - Louisvdw/dbus-serialbattery: Battery Monitor driver for serial battery in VenusOS GX systems
Battery Monitor driver for serial battery in VenusOS GX systems - Louisvdw/dbus-serialbattery
Thank you for your response.
Yes, I have the USB-RS485 box and connectors. Thank you for the wiki link.
Louisvdw
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https://github.com/Louisvdw/dbus-serialbattery/releases/tag/v0.7 now include support for the Daly Sinowealth based BMS ( normally the 3/4 cell Daly versions) and also the JKBMS / Heltec BMS
great work,
Unfortunately you the electrodacus isn't included yet. For my understanding does bms thru venus device now control the charge sources that are connected to the venus device? So the multiplus assistant with the allow to charge discharge is not necessary?
I'm building a 12 volt lifepo system and have a 3kw multiplus as the biggest consumer. If the BMS signals an overcharge event on cell level will the software tell the Multi to stop charging via the venus device? If so i could directly connect the multi to the battery and the small domestic loads can be connected to the say a 100 amp daly BMS. In that way the multi is controlled by the BMS thru the venus device. Is this so? ore is the charge current only trotheled back on soc and pack voltage?
Unfortunately you the electrodacus isn't included yet. For my understanding does bms thru venus device now control the charge sources that are connected to the venus device? So the multiplus assistant with the allow to charge discharge is not necessary?
I'm building a 12 volt lifepo system and have a 3kw multiplus as the biggest consumer. If the BMS signals an overcharge event on cell level will the software tell the Multi to stop charging via the venus device? If so i could directly connect the multi to the battery and the small domestic loads can be connected to the say a 100 amp daly BMS. In that way the multi is controlled by the BMS thru the venus device. Is this so? ore is the charge current only trotheled back on soc and pack voltage?
Louisvdw
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@FKZ there is a ticket open to look at the ElectroDacus SBMS0 integration. If someone would like to donate a BMS that we can use for the integration and testing that always helps a lot.
The driver handles the battery settings on the ESS system so that it will work just like a battery that is offically supported by Victron. You can find more details on the features that the driver support on the wiki, but in short any battery feature that is supported by official supported batteries the driver can do as well, if the BMS support that data (most do, or is omplemented in the driver as well). Just note the alarms arestill outstanding for the Daly BMS.
You still need the ESS assistant, as that is the fallback settings when your GX device or battery is offline, but the driver will override the charge/discharge limits and settings. This means it will tell the Multiplus what to do. If the battery is full it will tell the Multi/MPPT to stop charging. If it is empty it will tell the Multi to stop discharging. If there is a cell with overvoltage your BMS will raise an alarm and the driver will raise that alarm on the VenusOS (GX) system as well. However the BMS is the one that in the event of an alarm also say if (dis)charging stops. The driver will just translate that to the VenusOS system. (in the event of an overvoltage all the BMS I have seen also stop charging, so it work like you expect)
You should never bypass your BMS and put a load directly on a lithium battery.
It is very important to understand who is responsable for what in your system.
The BMS is there to keep your battery safe (so that it does not burn down your house).
The Inverter is there to give you power and it will override what the battery tells it to do for small periods to best give you the power you ask for. So even if the BMS tell it to stop (dis)charging it will still push and pull (normally smaller) current from the battery to give you a stable power curve and avoid spikes. The BMS will allow this while the SOC is at 100%, but when an overvoltage happen the BMS will protect the battery.
The driver handles the battery settings on the ESS system so that it will work just like a battery that is offically supported by Victron. You can find more details on the features that the driver support on the wiki, but in short any battery feature that is supported by official supported batteries the driver can do as well, if the BMS support that data (most do, or is omplemented in the driver as well). Just note the alarms arestill outstanding for the Daly BMS.
You still need the ESS assistant, as that is the fallback settings when your GX device or battery is offline, but the driver will override the charge/discharge limits and settings. This means it will tell the Multiplus what to do. If the battery is full it will tell the Multi/MPPT to stop charging. If it is empty it will tell the Multi to stop discharging. If there is a cell with overvoltage your BMS will raise an alarm and the driver will raise that alarm on the VenusOS (GX) system as well. However the BMS is the one that in the event of an alarm also say if (dis)charging stops. The driver will just translate that to the VenusOS system. (in the event of an overvoltage all the BMS I have seen also stop charging, so it work like you expect)
You should never bypass your BMS and put a load directly on a lithium battery.
It is very important to understand who is responsable for what in your system.
The BMS is there to keep your battery safe (so that it does not burn down your house).
The Inverter is there to give you power and it will override what the battery tells it to do for small periods to best give you the power you ask for. So even if the BMS tell it to stop (dis)charging it will still push and pull (normally smaller) current from the battery to give you a stable power curve and avoid spikes. The BMS will allow this while the SOC is at 100%, but when an overvoltage happen the BMS will protect the battery.
Louisvdw the electradacus is setup in the way that the BMS controls the charging and discharging by enabling/disabling the charge/ discharge source. There is no big main contractor or fet based switch to isolate the battery in case of an hazardous over/under voltage event. could be set up that way bu by using a multiplus it will interact directly with the charge/discharge source.
With your software basically all the bmses get the function to control a multi in a way i find preferable the bms cuts the charge source not the bms disconnects the complete battery.
this is the way victron has implemented their lifepo B management S. Not a B safety S that most cheap fet based BMSes are. Without a venus device and your software most cheap BMS manage nothing except the last undesirable action to disconnect the battery.
If victron/REC/Batrium/MG/Electradacus trust the venus and/or the multi software to be stable and manage the charge/ discharge i put my trust in them.
It's not that i want to cut corners but if only one device uses a 250 amp current that can be programmed to do wat a small Battery Management system wants it to do i see no harm in wiring it outside the bms sinds it is still controlled by the BMS. The other users are in the 50 amp max range that is why i opted for the electradacus control the multi and the MPPT for charging. uses a fet based switch to control the smaller DC load and management is done.
If you use the supported BMS without a venus device you still need to program chargers and users to cut of at a certain pack voltage HV/LV and not just wait till the main fets disconnect the battery. The feedback on cell voltage and taking appropriate action to the connected victron gear is wat is missing in the victron range. Your software enables this control over victron chargers on a cell level making them managers instead of last protection resorts. Will look in to the supported types if
With your software basically all the bmses get the function to control a multi in a way i find preferable the bms cuts the charge source not the bms disconnects the complete battery.
this is the way victron has implemented their lifepo B management S. Not a B safety S that most cheap fet based BMSes are. Without a venus device and your software most cheap BMS manage nothing except the last undesirable action to disconnect the battery.
If victron/REC/Batrium/MG/Electradacus trust the venus and/or the multi software to be stable and manage the charge/ discharge i put my trust in them.
It's not that i want to cut corners but if only one device uses a 250 amp current that can be programmed to do wat a small Battery Management system wants it to do i see no harm in wiring it outside the bms sinds it is still controlled by the BMS. The other users are in the 50 amp max range that is why i opted for the electradacus control the multi and the MPPT for charging. uses a fet based switch to control the smaller DC load and management is done.
If you use the supported BMS without a venus device you still need to program chargers and users to cut of at a certain pack voltage HV/LV and not just wait till the main fets disconnect the battery. The feedback on cell voltage and taking appropriate action to the connected victron gear is wat is missing in the victron range. Your software enables this control over victron chargers on a cell level making them managers instead of last protection resorts. Will look in to the supported types if
Louisvdw
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I think we are saying something similar.
Can it work they way you describe? Yes it will work.
Is it safe? Not according to me, No
Do I recommend anyone doing this? No
Is it legal in your country? Probably not, but I don't know.
(Now with all the disclaimers out of the way a bit more detail
)
I would still say that you need both the BMS and the control interface link that controls your charging. It's not a one or the other scenario.
The driver links the battery to the system and then the system manages the charge/discharge. So the BMS never disconnects in normal usage, which is what you want.
But the inverter will also ignore that command to keep the power stable if it needs too. You will see this happen when a large load stops suddenly and the battery is at 100% SOC. Another place where you will see an indication of this is when there is a negative power draw from the grid even if you told the ESS to not push power into the grid.
When this happens the battery will either have capacity to handle this, or it will push the battery into protection mode. 99% of the time the battery will just soak this up, but you want the BMS protection to be there when it can't.
Also remember that there are delays in this path as well. The Multiplus ramps power delivery up and down and can take up to a few seconds to do that. 750ms extra if you use ET110 measurement device (worse for some of the other models) and the BMS/driver only update every 1-2 seconds depending on which BMS you use. You can have a problem scenario of up to 5-7seconds if you don't have the BMS in the circuit to disconnect.
Perhaps also look at what Victron recommends with their Lithium battery. You will see in their product page it requires one of the listed BMSes and each of those BMS will disconnect the battery when a problem event happens (it is in their product description).
Can it work they way you describe? Yes it will work.
Is it safe? Not according to me, No
Do I recommend anyone doing this? No
Is it legal in your country? Probably not, but I don't know.
(Now with all the disclaimers out of the way a bit more detail
)I would still say that you need both the BMS and the control interface link that controls your charging. It's not a one or the other scenario.
The driver links the battery to the system and then the system manages the charge/discharge. So the BMS never disconnects in normal usage, which is what you want.
But the inverter will also ignore that command to keep the power stable if it needs too. You will see this happen when a large load stops suddenly and the battery is at 100% SOC. Another place where you will see an indication of this is when there is a negative power draw from the grid even if you told the ESS to not push power into the grid.
When this happens the battery will either have capacity to handle this, or it will push the battery into protection mode. 99% of the time the battery will just soak this up, but you want the BMS protection to be there when it can't.
Also remember that there are delays in this path as well. The Multiplus ramps power delivery up and down and can take up to a few seconds to do that. 750ms extra if you use ET110 measurement device (worse for some of the other models) and the BMS/driver only update every 1-2 seconds depending on which BMS you use. You can have a problem scenario of up to 5-7seconds if you don't have the BMS in the circuit to disconnect.
Perhaps also look at what Victron recommends with their Lithium battery. You will see in their product page it requires one of the listed BMSes and each of those BMS will disconnect the battery when a problem event happens (it is in their product description).
Thanks for the explanation It is a stand alone unit in a boat so not 100% on and not grid connected so no feed back to the grid. The electrical system is only on during weekends and vacation. The inverter only for cooking and charging the LFP battery If solar is not sufficient.
As far is i know only the Lynx serie has a built in contactor (developed by MG electronics) Al other victron BMSes use and I quote from the manual:
3.3. The BMS Besides making above pre-alarm signal available, the main purpose of the BMS is to control the chargers and the loads. There are two ways that it can do that: 1. By sending a signal to the charger or load. 2. By physically connecting or disconnecting a load or a charge source from the battery, using for example a large contactor.
The voltages to disconnect voor LV en HV are conservative. For the victron BMSes there is no difference if the signal goes to a multi or a relay. Using relais results in a charge and discharge circuit. There is no 2nd safety to stop the charging if the multi/ contactor doesn't react to the signal. In both cases possible damage to the battery is the risk.
As in most boat systems a main switch is located near the battery if the alarms go of and the dis/ charging wont stop this should be manually operated. to isolate the battery from the rest of the system.
As far is i know only the Lynx serie has a built in contactor (developed by MG electronics) Al other victron BMSes use and I quote from the manual:
3.3. The BMS Besides making above pre-alarm signal available, the main purpose of the BMS is to control the chargers and the loads. There are two ways that it can do that: 1. By sending a signal to the charger or load. 2. By physically connecting or disconnecting a load or a charge source from the battery, using for example a large contactor.
The voltages to disconnect voor LV en HV are conservative. For the victron BMSes there is no difference if the signal goes to a multi or a relay. Using relais results in a charge and discharge circuit. There is no 2nd safety to stop the charging if the multi/ contactor doesn't react to the signal. In both cases possible damage to the battery is the risk.
As in most boat systems a main switch is located near the battery if the alarms go of and the dis/ charging wont stop this should be manually operated. to isolate the battery from the rest of the system.
vk2emp
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Good stuff - I'll start playing with my 2 12V Daly's on a 40A Headway pack and a 180Ah Calb pack
@Louisvdw The way I see this working would be let the BMS work with the GX in main control, but then also program one of the SBMS extio (optocouplers) to type 5. Here is the explanations of the different settings you can use in the SBMS0 (oddly NOT listed in the manual online):
type 1 is for chargers and the EXT IOx will be open circuit if any cell exceeds the upper set limit as an example 3.55V for LiFePO4
type 2 is what you will use for an inverter and EXT IOx will be open circuit if any cell is below low limit example 2.8V for LiFePO4
type 3 and type 4 are mostly for alarms and are based on SOC that you set.
type 5 is for cases where SBMS maybe fails to turn OFF the charger or a Load so it will react if second limits are reached like overvoltage lock or undervoltage lock (should never happen unless something gets damaged) the signal can be used for an alarm if is a supervised system or for a breaker trip device that can disconnect a breaker cutting the PV inputs and the inverter so battery is protected in case of a hardware fail.
You could then hookup a large contactor (with precharge circuit) along with a larger solid state relay as the base optocouplers only support 50ma. Then if the GX fails to do what it's told, the relay will open and disconnect the battery.
If this sounds like a good plan, I'll send you my SBMS0 (if I can get it back when you are finished). Shoot me a PM if you want to discuss.
type 1 is for chargers and the EXT IOx will be open circuit if any cell exceeds the upper set limit as an example 3.55V for LiFePO4
type 2 is what you will use for an inverter and EXT IOx will be open circuit if any cell is below low limit example 2.8V for LiFePO4
type 3 and type 4 are mostly for alarms and are based on SOC that you set.
type 5 is for cases where SBMS maybe fails to turn OFF the charger or a Load so it will react if second limits are reached like overvoltage lock or undervoltage lock (should never happen unless something gets damaged) the signal can be used for an alarm if is a supervised system or for a breaker trip device that can disconnect a breaker cutting the PV inputs and the inverter so battery is protected in case of a hardware fail.
You could then hookup a large contactor (with precharge circuit) along with a larger solid state relay as the base optocouplers only support 50ma. Then if the GX fails to do what it's told, the relay will open and disconnect the battery.
If this sounds like a good plan, I'll send you my SBMS0 (if I can get it back when you are finished). Shoot me a PM if you want to discuss.
Louisvdw
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That is perfect. Even if it is an external circuit that your BMS controls, it will give you protection from what the BMS.
All SBMS0 owners, I'm going to be sending off my SBMS0 to @Louisvdw once I get an address. If you feel like donating to help me replace my SBMS0, please shoot me a PM and I can send you my paypal address if you want to chip in. I'll take half the donations (to recoup my costs for the SBMS0) and the other half I'll send to Louis.
interestingfellow
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Thank you! This is exactly what I was trying to figure out how to do! (I am not a programmer! LOL)
I can not wait to try this with my Daly 250 Smart BMS.
I can not wait to try this with my Daly 250 Smart BMS.
Hope someone can help. I am a newbie.....
Have ordered 16 x 280 cells for a 48v system and need to order the JBD BMS to match but I am confused on Aliexpress!
I THINK the options are:
200A with UART https://www.aliexpress.com/item/100...o.store_pc_groupList.8148356.8.43f57277iE2eTp
then add an RS485 interface
OR
100A "SMART" which includes UART/RS485 and CAN: https://www.aliexpress.com/item/100...o.store_pc_groupList.8148356.6.6ae86333H4dyct
Price doesn't matter, just want the right one that is most capable. Would prefer the 200A if that works.
And... again, sorry for newbie question; will this top balance or do I need something else to do that? If so, what would be a good option?
Thanks in advance.
Dean
PS, thanks @Louisvdw for your posts, it has made this journey much easier.
Have ordered 16 x 280 cells for a 48v system and need to order the JBD BMS to match but I am confused on Aliexpress!
I THINK the options are:
200A with UART https://www.aliexpress.com/item/100...o.store_pc_groupList.8148356.8.43f57277iE2eTp
then add an RS485 interface
OR
100A "SMART" which includes UART/RS485 and CAN: https://www.aliexpress.com/item/100...o.store_pc_groupList.8148356.6.6ae86333H4dyct
Price doesn't matter, just want the right one that is most capable. Would prefer the 200A if that works.
And... again, sorry for newbie question; will this top balance or do I need something else to do that? If so, what would be a good option?
Thanks in advance.
Dean
PS, thanks @Louisvdw for your posts, it has made this journey much easier.
Louisvdw
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@BigDean, the 200A model use a relay to switch the battery on/off while the 100A model use a bank of FETs. Both work fine, but I don't think it is economical to add enough FET chips to handle 200A, while the relay (this one with a precharger which is good) has some other drawbacks like being slower to switch.
If the 100A will be enough for your system, then I would suggest that model rather than the relay.
How do you know it will be enough for your needs? That depends on the power you need and intend to draw. 100A x 51V = 5100Watts so if you have a 5kW inverter 100A is your limit in any case.
You need the RS485 or UART interface. The driver don't use CAN. If you can make sure it has an extra interface. On the JBD the bluetooth normally is installed on the UART, so if you get the RS485 port extra then that mean you have the bluetooth and connection to the driver at the same time which is nice.
This will top balance your battery, but you will have to give it time to do that. So build your cells and install the BMS and charge it to around 80-90%. Then disconnect the charging and set the BMS to balance always (and not just on charging) and leave it for about a week. Check daily if the cells have settled and if it is still balancing and you can also top up the charge a bit if you want. You can extend this to two weeks if your battery needs more time. Then switch the balancing back to only on charge and you can begin using it in your system. The BMS should then keep your cells balanced from there on.
If the 100A will be enough for your system, then I would suggest that model rather than the relay.
How do you know it will be enough for your needs? That depends on the power you need and intend to draw. 100A x 51V = 5100Watts so if you have a 5kW inverter 100A is your limit in any case.
You need the RS485 or UART interface. The driver don't use CAN. If you can make sure it has an extra interface. On the JBD the bluetooth normally is installed on the UART, so if you get the RS485 port extra then that mean you have the bluetooth and connection to the driver at the same time which is nice.
This will top balance your battery, but you will have to give it time to do that. So build your cells and install the BMS and charge it to around 80-90%. Then disconnect the charging and set the BMS to balance always (and not just on charging) and leave it for about a week. Check daily if the cells have settled and if it is still balancing and you can also top up the charge a bit if you want. You can extend this to two weeks if your battery needs more time. Then switch the balancing back to only on charge and you can begin using it in your system. The BMS should then keep your cells balanced from there on.
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