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2011 Zero S Battery replacement?

That is 10 cells in the front with terminals facing aft, against a firewall and 6 terminals up in the tail.
Dimensions might be t0o narrow tolerance. Will know when the OEM battery is retired. I don't plan to dismantle and replace until that point. Unless I find a spare empty case for this year/model.
 

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A little progress... And another challenge:
Does anyone know the MBB password(s) for a 2011 Zero S?

I tried 2 of the recurring search result passwords. Neither worked (1.2gigawatts, tpsreports). I also tried a few generic default style (00000, 01234) since there doesn't appear to be a limit on attempts.

Why ask for the password if all I'm wanting to do at this point is read the status of the battery health and not yet make any changes?

Well, once the key is switched on, the password prompt comes up immediately after a small startup list of processes passes on the console (firmware listing, pre charge success, BMS connect success, etc.).

I have not figured out how to access the 'read-only' information, which I supposed was the default level based on some internet researching (including the helpful works of @Doctorbass).
 

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Well... I am in now.
Base level password confirmation:
1.21gigawatts

Laughable user error was the problem. I was having trouble with the double enter command needed to submit the password.

I have not tested the listed level 2 password for making changes (tpsreport). I might steer clear of that for now until I get more friendly with the software.

Hope to find time for getting a BMS report tonight :)

Side note, anyone have a clue on adjusting the word wrap in Putty? The checkbox terminal setting doesn't seem to alleviate the content getting oddly justified and pretty illegible.
 

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Adjusted the PuTTy settings per the link @Floyd and it still didn't seem to correct the issue of each text line being tabbed progressively further to the right, and word wrap anomalies...

I was able to copy and paste the otherwise difficult to read terminal readout into notepad, and post-process to a bit more legibility. Maybe this is an echo setting issue, where its doubling (or more) the number of characters for the tab so all subsequent rows get progressively more offset? Or maybe its representing tab differently than this x64 system is interpreting?

My description of this error is rough. Though it genuinely seems like there is an easy solution to this.

One notable concern that surfaced during my first session last night with the purpose of finding the health of the battery... I got home after work and a long route (nice weather here). There was still 40-50% capacity left in the battery per the dash meter. I plugged in, and logged on to print some stats and information on the battery SOH. When I hit the command for 'bms' the dash meter capacity reading went to empty (blank), as did the resulting measurements in the bms print out (see attached photo). This made me concerned, with catastrophic thoughts like, oh gosh Zero put some sort of back end block to trash the battery if logon was sketchy?? Then I though, and hoped, it was just some random glitch and the best thing I could do was logout, shut the bike down, and plug in for an overnight (balance) charge...

Look at the spec sheet though... it says all the cells were at a very low voltage. Yet, I had just rode it for at least 5 miles at speeds of 35-55 mph. Then after I bailed on the session after getting the anomalous reading, it started and drove fine the remaining distance to the garage, e.g. no volt sag and all lights and accessories were working as if the battery was still at ~50%.

That leads me to suppose that there was just some software glitch or user error in my navigation of the oddly tab justified console. Perhaps there is a voltage calibration setting for the bms or something, and now after an overnight charge, it automatically or I can manually reset?

I'll be starting up the bike in a bit to see what overnight charge did for the anomalous bms reading. Will report that back here later today.

Has anyone that had or has one of these earlier (gen1 or gen2) bikes exhibit a similar anomaly?

Side note, during this logon session and prior to the bms stat print below, I found that the blinking error light on the dash was indeed indicating a BMS CANbus error. Is it possible, this battery is actually a replacement and the BMS was bypassed or spoofed?

1787142615558.png
 
After some brief research, I am finding that my problem could be that these two checkboxes were open (see photo circled in green).
I just checked them and saved the configuration, and will test shortly....

1787143215978.png

The information I sourced for this possible fix:

1787143382809.png
 
Battery okay ... Though I have a concern. The discussed point about the dash 'fuel' gage previously sorta came full face yesterday.

This has to do with LVC. Does this battery have the capacity to enact a LVC and protect the batteries from over discharge?

I went for a ride yesterday, and by the time I made it to the turn around point the battery showed 0%. That is from a full charge when leaving prior, about 12 miles. Granted I was maintaining about 50mph that whole time, which is more energy used than my previous range estimations with lower speeds (30-40mph).

At that halfway point there was nowhere to plug in. So I figured, I would just keep going, throttle back, and hope the distance I had to push a 300lb bike through rolling hills before a storm would be short.

Well... I rode about 12 miles as the battery gage constantly flashed 0%, though with no obvious voltage sag occuring.

When I checked the BMS status from the MBB console after, all the cells were at around 3.6v and that is the concerning bit...

If I had longer to go, would the BMS have continued to let me travel despite approaching or surpassing the LVC? What happens when you ride past the LVC voltage knee on this original batteries discharge curve? Maybe a new LVC is a setting I should consider adjusting with elevated MBB logon (password: tpsreport)?

This test gave me this sense that ... Not only will the eventual battery replacement provide me more range, it might do so with a great deal more safety because I can more consistently monitor battery voltage with a Bluetooth module, as well as directly adjust the LVC with the Orion 2 Jr.

How do the early Zeros (2010-2012) estimate range, and why on earth would it be so inaccurate? I mean, based off yesterdays ride, when the gage reads 0% I'm halfway? Is it doing true columb counting? Maybe this is a symptom of an aged battery: the BMS's capacity estimate decreases accuracy with battery age?
 
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Side note, preventative maintenance suggests around 3k km (or greater) I might need to service the carbon brushes... When looking for the parts, I only find shops with 'no longer for sale' if they even have the item listed. So far no source.

Is this a sign that, when the brushes go I will need to migrate to an alternative DC motor that works with the Altrax onboard, or convert to BLDC/3phase motor system (moto +controller)?
 
When I checked the BMS status from the MBB console after, all the cells were at around 3.6v and that is the concerning bit...

If I had longer to go, would the BMS have continued to let me travel despite approaching or surpassing the LVC? What happens when you ride past the LVC voltage knee on this original batteries discharge curve? Maybe a new LVC is a setting I should consider adjusting with elevated MBB logon (password: tpsreport)?

This test gave me this sense that ... Not only will the eventual battery replacement provide me more range, it might do so with a great deal more safety because I can more consistently monitor battery voltage with a Bluetooth module, as well as directly adjust the LVC with the Orion 2 Jr.
I think that is what I found too, the cells where at 3,6v when it showed empty. I don't know about the bms or MBB, but the motor controller has a LVC you can adjust. I think it is set to just over 41V, so a little over 2,9V/cell.
Probably the MBB and/or the bms cuts before that. The MBB can do it nicely, with gradual power reduction, as it controls the throttle input to the motor controller.

Sure, a bms where you more easily can monitor the voltages would help, but why not just add a little voltmeter?
No modification to the battery and very little to the bike.
Then you can see the total voltage and learn how low you can go, and check the cell voltage data from the bms on this program you found so you can see if they stay in balance.

I don't know how low you can go on these cells, but 3,6v sounds high :unsure:
 
total pack voltage with Voltmeter is a good first step, good point @j bjork. Then just divide by 14s assuming per cell v.

Hopefully the BMS would catch if there is a considerable offset in the balance of that assumption.

0% reading at the turn.arlund point for half (~17 miles) the total distance traveled (~30 miles) being a drop from 57.96v (4.14v/cell) to 50.40v (3.60v/cell).
 
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Would be cool to see some of the software #annotations for this, to see if there are descriptions of meanings.

Example, when I set "scale" to 3% (from the previous 57%) there was no throttle response at all, as in the motor received no drive signal. When I set at the last line here shows, it back past to 88% it is exaggerated only a bit it felt like 57%, though that test was only at low speed (<10 mph).

Is "scale" a multiplier?
How do I activate the low/med/eco sp(speed) and tq(torque) options?

Or, what is "Throttle Map" setting "Curve 7"?

I'd like to optimize for endurance instead of performance. Even, muse other uses for the power system when 'parked'. Like solar shelter, or running an electic grill and cooking for friends.

I also have noticed that the settings adjustments do not necessarily maintain during shutdown, and there has been a reversion to a default value. Which, maybe there is a problem with the dc/dc...

We'll see. Looking forward - already have 140 ish miles ranging from 5 - 40 mph, and a few bursts to see safe hwy speeds round here at ~63mph. The frame is light so the high speeds just feel a bit wind ... baring. Might need to turn the suspension thou.

Code:
*************************************************************
*                   System Settings Menu                    *
*************************************************************

  serial          - Board Serial Number     :  5774
  mode            - Motor Control Mode      :  Torque
  lowsp           - Low Mode Speed Pct      :  65%
  lowtq           - Low Mode Torque Pct     :  59%
  medsp           - Medium Mode Speed Pct   :  100%
  medtq           - Medium Mode Torque Pct  :  84%
  econsp          - Economy Mode Spd Pct    :  100%
  econtq          - Economy Mode Torque Pct :  70%
  rate            - Throttle Ramp Rates     :  Full Up    - 20
                                               Full Down  - 30
                                               Min Up     - 7
                                               Min Down   - 14
  scale           - Output Scale Factor     :  3%
  error           - Allowed Throttle Error  :  750mV
  peak            - Max Peak Current        :  450 A (90 %)
  maxspeedpct     - Max Speed Pct           :  100%
  maxmph          - Max Speed MPH           :  100
  maxmphstart     - Speed limit start MPH   :  100
  maxmphp         - Max Speed MPH P Term    :  512
  pid             - PID values (up-down)    :  P:75-250 (350), I:0-0, D:0-0
  .               - Throttle Type           :  0-5K Pot
  map             - Throttle Map            :  Curve 7
  tempcut         - Temp Cutoff Enabled     :  No
  prot            - Motor Temp Protect Mode :  Current Taper
  stage1          - Motor Temp Stage1       :  125 C, (50 ADC)
  stage2          - Motor Temp Stage2       :  135 C, (40 ADC)
  stage3          - Motor Temp Stage3       :  155 C, (27 ADC)
  tempreen        - Motor Temp Reenable     :  90 C, (112 ADC)
  tempfan         - Motor Temp Fan On       :  70 C, (183 ADC)

  plsper          - Pulse Period            :  500 ms
  plswid          - Pulse Width             :  50 ms
  taperstart      - Motor Temp Taper Start  :  135 C
  taperend        - Max Amps @Cutoff        :  49 A
  fanstart        - Fan On at Startup       :  2000 ms

  prethr          - Precharge Threshold     :  39984 mV
  pretime         - Precharge Timeout       :  10000 ms

  contenoff       - Contactor En Max Off    :  20000 mV
  contopen        - Contactor Open Max      :  98 %
  coiltestv       - Cont Coil Test Voltage  :  3000 mV
  coilmintest     - Cont Coil Min Drop Test :  7385 mV
  coilmaxtest     - Cont Coil Max Drop Test :  10000 mV
  coilminnorm     - Cont Coil Min Drop Norm :  40000 mV
  coilmaxnorm     - Cont Coil Max Drop Norm :  60000 mV

  spfront         - Sprocket Teeth Front    :  28
  sprear          - Sprocket Teeth Rear     :  98
  rwhcirc         - Rear Wheel Circum       :  7351 in*100
  fuel            - Fuel Gauge Type         :  Current
  kill            - Kill Switch Polarity    :  openrun

  motlogint       - Motor Log Interval      :  1000 ms

  restore         - Reset all system settings to defaults

  exit            - Exit to Main Menu

ZERO SETTINGS> scale 88%
  Value was set to 88%

ZERO SETTINGS>
 
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