ElectricMotorcycleForum.com

My speculative guess is:

• Overall voltage would be the minimum of the two batteries. Of course, they're electrically connected and maybe there's just a single bus measurement that the MBB uses separate from each BMS.
• Cell balance would be a maximum of each BMS' cell balance figures (which are maximums). I wouldn't expect the MBB to read the highest and lowest cells from each BMS and then calculate cell balance of them all together, but maybe it does! I don't know whether that'd mean anything for battery management or be confusing, because cell balancing has to happen per-pack.

Corrections welcome.

> > if you have access to the mbb console, you can run the "bms" command, see if it reports status separately.
> >
> > i'm told the architecture of the Zero mbb platform to date supports up to two battery subsystems.  ...

> My speculative guess is...

Anyone out there have a diginow reaper/dongle *and* a powertank?  Or a diginow dongle and a two-brick X platform bike?

Would you be willing to capture the output of "bms" and post it?  Remove VIN and any other sensitive info before posting, of course...

SR-2015 with powertank (recorded early this year when I was doing some diagnostics after my bike was recovered after its theft)
Monolith is BMS #0
Powertank is BMS #1

****************************************
*               BMS Data               *
****************************************

*************  BMS #0  ***************
  - BMS Board Rev             :  03
  - BMS Firmware Rev          :  37
  - BMS Serial Number         : 2015_bms_03b9fc_00770
  - Battery Serial Number     : 15qd0574
  - CAN Rx in last second     :   74

  - Pack SOC                  :  49%
  - Fuel Gauge                :  47%
  - Age of SOC Data           :  20 ms

  - Model Year                : 2015
  - Pack Capacity             : 100 AH
  - Pack Capacity Remaining   :  48 AH
  - Total Energy Used         : 366 KWH
  - Number Of Bricks          :   4

  - Pack Discharge Current    :   2 A
  - Pack Sum Voltage          :  102.203 V
  - Sag-Adj Pack Sum Voltage  :  102.263 V
  - Bank Voltages             :     1    2    3    4    5    6    7    8    9   10   11   12   13   14   15   16   17   18   19   20   21   22   23   24   25   26   27   28
                              :  3647 3650 3649 3649 3650 3651 3649 3650 3651 3652 3650 3649 3648 3650 3649 3650 3650 3651 3649 3651 3652 3651 3652 3650 3650 3651 3651 3650
  - Lowest Cell Voltage       :  3647 mV ( Cell 1 )
  - Highest Cell Voltage      :  3652 mV ( Cell 10 )
  - Pack Balance              :  5 mV
  - Lowest Cell mV            :  3647 mV
  - Age of Bank Voltage Data  :  238 ms

  - Isolation Resistance      :  1413 KOhms (0x0585)
  - Least Isolated Cell       :  0
  - Instant Iso Resistance    :  -13 KOhms (0xFFFFFFF3)
  - Instant Least Iso Cell    :  0

                              :      0     1     2     3     4     5     6     7
  - Pack Temps                :     7C    6C    6C    7C    7C    7C    7C    7C
  - Lowest Present Pack Temp  :  6 C
  - Max Pack Temp This Ride   :  7 C
  - Min Pack Temp This Ride   :  6 C
  - Age of BMS Temp Data      :  90 ms

  - Min Discharge Temp        :  -30 C
  - Max Charge Temp           :  50 C
  - Min Charge Temp           :  0 C
  - Max Charge C-Rate         :  1.0
  - Min Discharge C-Rate      :  7.5
  - Discharge Scale Value     :   227/255

  - Num Charge Cycles         :  225

  - BMS Total Bike Run Time   :  00:02:00
  - BMS Clock                 :  01/02/2017 05:31:57 ( 1483360317, 0x586A483D )
  - Age of BMS Time Data      :  206 ms

  - Age of BMS Status Data    :  219 ms
  - Discrete Throttle En      :  Enabled

  CAN Status
  - Charger Attached          :   No
  - Batt Unbalanced           :   No
  - Batt Low                  :   No
  - Batt Full                 :   No
  - Batt Critically Low       :   No
  - Batt Temp High            :   No
  - Batt Temp Critically High :   No
  - Batt Temp Low             :   No
  - Contactor Closed          :  Yes
  - Isolation Fault           :   No
  - BMS Internal Fault        :   No
  - Cell Too High For Charge  :   No
  - Cell Too Low For Charge   :   No
  - Charge Halt               :   No
  - BMS Internal Disable      :   No

  CAN Commands
  - Close Contactor           :   No
  - Connect Module            :  Yes
  - Key On                    :  Yes
  - Charger Connected         :   No
  - Expected Charger Current  :  N/A
  - Time Since Cmds Last Sent : 1986 ms

*************  BMS #1  ***************
  - BMS Board Rev             :  03
  - BMS Firmware Rev          :  37
  - BMS Serial Number         : 2015_bms_0386e1_01926
  - Battery Serial Number     : 15sg1599
  - CAN Rx in last second     :   77

  - Pack SOC                  :  49%
  - Fuel Gauge                :  47%
  - Age of SOC Data           :  56 ms

  - Model Year                : 2015
  - Pack Capacity             :  22 AH
  - Pack Capacity Remaining   :  10 AH
  - Total Energy Used         :  78 KWH
  - Number Of Bricks          :   1

  - Pack Discharge Current    :   0 A
  - Pack Sum Voltage          :  102.189 V
  - Sag-Adj Pack Sum Voltage  :  102.189 V
  - Bank Voltages             :     1    2    3    4    5    6    7    8    9   10   11   12   13   14   15   16   17   18   19   20   21   22   23   24   25   26   27   28
                              :  3646 3652 3651 3652 3649 3651 3650 3641 3648 3652 3653 3653 3651 3652 3647 3649 3642 3652 3647 3653 3647 3647 3645 3650 3649 3656 3652 3647
  - Lowest Cell Voltage       :  3641 mV ( Cell 8 )
  - Highest Cell Voltage      :  3656 mV ( Cell 26 )
  - Pack Balance              :  14 mV
  - Lowest Cell mV            :  3642 mV
  - Age of Bank Voltage Data  :  291 ms

  - Isolation Resistance      :  1346 KOhms (0x0542)
  - Least Isolated Cell       :  0
  - Instant Iso Resistance    :  -26 KOhms (0xFFFFFFE6)
  - Instant Least Iso Cell    :  0

                              :      0     1     2     3     4     5     6     7
  - Pack Temps                :     7C    7C    7C    7C -100C -100C -100C -100C
  - Lowest Present Pack Temp  :  7 C
  - Max Pack Temp This Ride   :  7 C
  - Min Pack Temp This Ride   :  7 C
  - Age of BMS Temp Data      :  91 ms

  - Min Discharge Temp        :  -30 C
  - Max Charge Temp           :  50 C
  - Min Charge Temp           :  0 C
  - Max Charge C-Rate         :  1.0
  - Min Discharge C-Rate      : 10.0
  - Discharge Scale Value     :   224/255

  - Num Charge Cycles         :  231

  - BMS Total Bike Run Time   :  00:02:00
  - BMS Clock                 :  01/02/2017 05:32:16 ( 1483360336, 0x586A4850 )
  - Age of BMS Time Data      :  205 ms

  - Age of BMS Status Data    :  217 ms
  - Discrete Throttle En      :  Enabled

  CAN Status
  - Charger Attached          :   No
  - Batt Unbalanced           :   No
  - Batt Low                  :   No
  - Batt Full                 :   No
  - Batt Critically Low       :   No
  - Batt Temp High            :   No
  - Batt Temp Critically High :   No
  - Batt Temp Low             :   No
  - Contactor Closed          :  Yes
  - Isolation Fault           :   No
  - BMS Internal Fault        :   No
  - Cell Too High For Charge  :   No
  - Cell Too Low For Charge   :   No
  - Charge Halt               :   No
  - BMS Internal Disable      :   No

  CAN Commands
  - Close Contactor           :   No
  - Connect Module            :  Yes
  - Key On                    :  Yes
  - Charger Connected         :   No
  - Expected Charger Current  :  N/A
  - Time Since Cmds Last Sent : 2803 ms

Yes as well I also had checked on the MBS log from the ans saw that too.

What i find very curious is that the Powertank have alot higher IMBALANCE than the monolith(less than 5mV).
That's the same thing Justin get as me for the imbalance except i get 27mV imbalance...

I will check the powertank imbalance at various SOC for fun...

Btw the powertank sticker indicate 102V 28Ah and not 29Ah

i also had similar strange info on a 2015 monolith where it was still wrote 25Ah on the brick and not 27Ah...

Doc

I made some wiki updates based on this:
http://zeromanual.com/index.php/Zero_Aftermarket#OEM_Power_Tank
http://zeromanual.com/index.php/Zero_Aftermarket#OEM_Power_Pack_Module