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Batrium balancing issue
#11
You can always use a 12v car headlight bulb clipped across cell 7 to manually balance it, but to be honest it looks so close to the rest of the pack it looks more like cells 6 and 9 need a hard charge. You can start an absorption charge and then clip the bulb across the cell, watch what goes on with 6 and 9
Current system: 9.6kWh wet Nicad batteries, 16S1P Calb LiFePo4 210aH, Batrium WM4, Outback vfx3048 inverter, mx60 mppt controller, flexware 500 mounting hardware, 2.4kW solar array, 6kW lister diesel genset. MY'13 Vauxhall Ampera
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#12
[quote pid='69405' dateline='1605181156']
Please let me know the settings you have for the absorption setpoint and timer from your Victron charger(s)
[/quote]


The absorption set-point is 49.8V (4.15 x 12) and at present I have it on scheduled charge for 12 hours per day (purely to support this test/commissioning phase)

During the other 12 hours it discharges only a small amount as it's only powering the Watchmon and Venus

(11-12-2020, 12:39 PM)HughF Wrote: You can always use a 12v car headlight bulb clipped across cell 7 to manually balance it, but to be honest it looks so close to the rest of the pack it looks more like cells 6 and 9 need a hard charge. You can start an absorption charge and then clip the bulb across the cell, watch what goes on with 6 and 9

Good plan, I think I need to do this to prove the issue either way
Batrium WatchmonPLUS / Victron Multiplus / 4kWh with plans for 40kWh
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#13
What's the absorption timer set to though?
Current system: 9.6kWh wet Nicad batteries, 16S1P Calb LiFePo4 210aH, Batrium WM4, Outback vfx3048 inverter, mx60 mppt controller, flexware 500 mounting hardware, 2.4kW solar array, 6kW lister diesel genset. MY'13 Vauxhall Ampera
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#14
Try to change around if you can and test to see if any of the others get warm. You should easily feel it get hotter while balancing hard for a longer amount of time.
NOTE! My links supplied in this message may be affiliated with Ebay and by clicking on them you agree on the terms.
YouTube / Forum system setup / My webpage  Diy Tech & Repairs

Current: 10kW Mpp Hybrid | 4kW PIP4048 | 2x PCM60x | 100kWh LiFePo4 | 20kWh 14s 18650 |  66*260W Poly | ABB S3 and S5 Trip breakers
Upcoming: 14S 18650~30kWh
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#15
This isn’t a problem with 6 and 9.

If WM says it’s balancing cell 7 and it doesn’t get warm, it’s stuffed.
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#16
(11-12-2020, 08:02 PM)slimf Wrote: This isn’t a problem with 6 and 9.

If WM says it’s balancing cell 7 and it doesn’t get warm, it’s stuffed.

This was precisely my thinking, however on further investigation I think I've got the answer.

While double checking the cell voltages with a multimeter so that I was applying a corrective charge to the correct cells, I noticed that while under balance, cell 6 was measuring 5V and cell 7 1.9V. Obviously something is seriously wrong there, so of course checked the multimeters accuracy on a bunch of other cells and it seemed fine.

While the watchmon was trying to balance cell 7;

Cell 6 was physically 3.96V (measured on cell) and was measured as 3.96V via the Watchmon - but actually had a voltage of 5.0on the harness between battery and Watchmon

Cell 7 was physically 4.16V (measured on cell and was measured as 4.16V via the Watchmon - but actually had a voltage of 1.7V on the harness between battery and Watchmon.

After some head scratching, I realised it was a high resistance connection between Watchmon and cell 6. While no current was flowing, it measured the correct voltage - however when the watchmon attempted to balance cell 7, the voltage between Cell 6 + and cell 7 + collapses.

It just happens that the Watchmon must have some level of filtering in the measurements that it still broadcasts a measured voltage of 4.15V - and still tells me that it is balancing the cell - however due to the lack of the red LED and heatsink staying cold, it doesn't actually balance (because the voltage is being pulled down when it tries to).

Anyway, long story short, I re-did that connection and it's happily balancing away now. Still some time to go until everything is level but at least it's operating as expected. Thanks for the tips everyone, got me to the solution quicker than I expected!

Cheap 4-life and OffGridInTheCity like this post
Batrium WatchmonPLUS / Victron Multiplus / 4kWh with plans for 40kWh
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#17
Well done for finding that, glad it is working for you now.
Current system: 9.6kWh wet Nicad batteries, 16S1P Calb LiFePo4 210aH, Batrium WM4, Outback vfx3048 inverter, mx60 mppt controller, flexware 500 mounting hardware, 2.4kW solar array, 6kW lister diesel genset. MY'13 Vauxhall Ampera
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#18
(11-12-2020, 12:37 PM)batteryshed77 Wrote:
(11-12-2020, 12:11 PM)daromer Wrote: Cant move 7th on the WM5 since its static position but you can move the pack itself

Does the wm5 become hot when balancing on the cell 7?  It should be hot if it actually balances.

It could be that balancer 7 is brooken perhaps?  Or as suggested just other cells very bad?

I believe it to be exactly this - because the Watchmon stays cold while it believes to be balancing cell 7. 

Even if the other cells were 'bad' they would eventually close the cap to cell 7 (given it has been on charge /balance for days now)

unfortunately I can't move the pack around, but I can charge cells 6 & 9 up a bit with an external charger to test my theory at least
Easy fix. Go to settings=> cellmon then check your bypass current 1.69A/temp 75c limits and bypass impedance1.7 Ohms. I screwed with this one time long ago and had the same results.
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#19
Eddy the problem was that it was not correctly wired from the start or atleast not good enough contacts.
NOTE! My links supplied in this message may be affiliated with Ebay and by clicking on them you agree on the terms.
YouTube / Forum system setup / My webpage  Diy Tech & Repairs

Current: 10kW Mpp Hybrid | 4kW PIP4048 | 2x PCM60x | 100kWh LiFePo4 | 20kWh 14s 18650 |  66*260W Poly | ABB S3 and S5 Trip breakers
Upcoming: 14S 18650~30kWh
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