retepsnikrep said:It' easy to discover which ID is which block during bench testing.
Plug them into a CAN monitor one at a time, see what ID pops up and write that on the block in marker pen!
jime said:The essential task would be to have each owner have a simple and inexpensive set of HW/SW to read the ID. That in place, we could all swap boards until everyone is happy.
If need be .. we could make an event at next Insightfest .. people bring their boards .. and we plug them into CAN-USB laptop , identify the CAN IDs for each board .. and if there is a conflict shuffle / swap to make non-conflict sets .. or outside of gatherings we could do the same thing , just with added shipping cost (the boards alone, are not very expensive to ship.)BTW, I have 23 BMS boards, believed to be operational, with an undetermined number of unique IDs.
My hunch .. is that we will not end up having to result to such switching .. but .. 'worst case' that should also work.retepsnikrep said:So it seems to be simply a matter of using a spare output on the BCM Replacer to control a 4053 2/3 way DPDT switch chip or similar.
Now there's a good idea - seems to me. Would avoid a bunch of folks having to try to set up unfamiliar equipment, and the cost of itIf need be .. we could make an event at next Insightfest .. people bring their boards .. and we plug them into CAN-USB laptop , identify the CAN IDs for each board .. and if there is a conflict shuffle / swap to make non-conflict sets .. or outside of gatherings we could do the same thing , just with added shipping cost (the boards alone, are not very expensive to ship.)
As far as the OEM BMS boards from Honda on the LTO modules .. As far as I know :So I've been looking at getting a pair of these LTO from Greentec, and found this thread and am glad to see it seems the circuit board on top does appear to be a BMS. If I don't care much about getting the information via the CANBUS, but do want the charge/discharge/balancing functionality, is there anything in particular I'd need to do other than use appropriate sized wiring for the main power terminals? Based on EndlessSphere link earlier in the thread, it seems that I need to supply power via the CANBUS connectors to the BMS boards in order to handle the charge/balancing?
Ah, I see, thank you. So folks have done some hard work, but only part-way there. If I really want a 'plug and play' type solution, I'd need a separate BMS that handles LTO cells, and then I can get simple "put the voltage in/out leads here".As far as the OEM BMS boards from Honda on the LTO modules .. As far as I know :
#1> Balancing is not automatic .. it must be commanded to do the balancing .. via sending the unit some (yet unknown) CAN message.
#2> So far using them as cell level voltage monitoring is as far as has been deciphered.
#3> Alternatively .. there are numerous other cell level balancing options out there .. just be careful the one you choose will do the LTO voltage range.
As for what else you need .. you will need .. something that monitors those cell level voltages ... and then takes action based on those voltages .. actions like .. Disable Charging when full .. Disable Discharging when empty .. take action to notify and protect when/if cells fail or get significantly out of balance .. and of course installing / mounting / connecting the cells-modules themselves.
I think the above sums it up well. These LTO packs seem quite stable, even for people with no BMS.Pretty much the case. The LTO solution is pretty simple for the initial manual capability. If one wants a fully capable BMS, then you would need to add a BMS such as the Orion.
It all boils down to what is good enough. Many experimenters think the LTO packs themselves are good enough because they are quire stable and maintain balance quite well. An occasional manual rebalance might be needed.
A step more "managed" is to use the top balancing chips which retepsnikrep has recommended. They balance on charge, so they do a pretty good joy with LTO.
If you want active minute to minute balance, then something like the Orion is needed.
Non of this is drop in, nor will it ever be. You have to be an experimenter at heart, but many such folks are making it work
Most BMS's in the solar industry are built around other chemistry batteries. The reason they don't balance is most do their balancing near the top of the voltage curve and for liion or lifepo4 that is higher than LTO. The top for LTO is 2.7V and thus never hits a voltage where those BMS's start to balance (which for those types is usually around 3.6V). If you search for it you can find LTO specific BMS's for solar but the easiest route is probably to use a programmable BMS (sometimes called a "smart" bms that runs Ant BMS software). In those you set the high and low voltage cutoffs on your phone and also set at what voltage you want it to start balancing.Thank you. I will bare my ignorance and ask you what the name of your YouTube channel is and, because I am new to this forum, how to navigate to find your written information. Electrical terminology is something I am having difficulty grasping so, I beg you to bear with me for asking questions that sound absolutely ridiculous to you. I have been one who can immediately imprint knowledge working hands on beside someone instructing me but, have difficulty grasping things in this area not knowing how certain functions are applied through reading. If it was possible, when viewing videos, to ask questions when one doesn't immediately understand something they see being done on a video, it would be most helpful. I have watched videos repeatedly when one small element is assumed by the presenter that skews the ability of the viewer to duplicate what is being presented.
You certainly have excellent knowledge of everything in this field and I only mentioned that you might have awareness of viewers who have none that are using you as a mentor for knowledge from your presentations.
Again, I graciously thank you for responding to my dilemma and will look forward to learning from you.
It looks like we need document mentioned above..(2) Cell voltage balancing
CMU receives the balance signal “1：Enable” from the BMU and it starts the balance circuit.
It starts the cell balance (discharge) control to a target voltage (typically：10 mV).
During voltage measurement, the CMU stops balancer temporarily in order not to affect the
If the target voltage is higher than all of the cell voltages in the system at that time, or if
there are cell voltages higher than 2.8V, or if there are cell voltages lower than 2.1V, then the
balance feature does not work.
(3) CAN communication features
CAN communication I/F and BMU specifications are as follows. Data, such as control instructions from the BMU, temperature and voltage, and module status are transmitted via
CAN communication. For structures of the data frame and definitions of the send/receive
frame, please refer to “Stationary Battery Module BMU development guide (6E6V0058)”.