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italianuser

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Feb 25, 2020
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335
Well sure you can swap out single cells but that would change the parameters of the the other cells when doing so! What a stupid design. If you swap out 1 cell then you have to reset the test (NOR test) for the rest of the cells and start all over with the rest of the cells!! So its either test 1 cell at a time or wait for all 4 to get done. That's dumb.
What? Oh my, mine don't change anything, I have 3 units but not the problem you say... I would have gone mad testing 1200 cells with the problem you say... maybe you have some other strange problem (?).

And I do keep an eye on timing, it always takes more or less the same time for similar cells.

There is a bug (Microsoft would call It a feature) that changes parameters if you quickly insert 4 cells in an empty unit: the settings of a cell influence previous cell but only in one direction (if I remember right It happens when quickly inserting cells from slot 1 to 4).
 

Duchess

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Aug 1, 2021
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Lets say you have all 4 cells inserted doing a NOR test. Cell #3 is done testing. You swap out cell#3 for a different one and press the mode button twice to select NOR test. The cells in 1,2 and 4 were on NOR test but since you pressed the mode button twice for cell #3, 1,2 and 4 have now changed from NOR test to CHARGING then Quick Test and start all over again. If you were to then press the mode button again on 1,2 or 4 to select NOR test again.... cell #3 moves 2 modes to Quick Test. What a stupid design. The ZanFlare ones you can at least change the mode on 1 cell without changing the parameters of the others.

I fought with them for a while until I gave up and tossed them. It would take me all day to just test 30 cells when I can get about 100 done a day with the ZanFlare devices.
 

Duchess

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This should be enough to start off right? More?

1628878814274.png
 

italianuser

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Feb 25, 2020
Messages
335
This should be enough to start off right? More?

View attachment 25835
Good start! But what I did is to test all cells (1120 for four 2.5KWh batteries) before building. That's because I want to make all parallel blocks more similar as possible and I could only do that after testing all cells.

For your charger problem I can tell you that mine don't have it. If I swap out a cell when NOR test Is finished and put a new Cell in, settings don't influence other slots. Could be maybe a newer firmware, I can't think of other reasons.
 

Duchess

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Each cell is tested, stored for about a month and tested again before assembling into small packs using repacker. Each pack is then tested for capacity and stability. I have a pretty sophisticated testing procedure. I haven't really found a retail device (charger/tester) that can properly do IR and or accurate voltage readings for the cells.
 

Wolf

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Sep 25, 2018
Messages
1,561
I haven't really found a retail device (charger/tester) that can properly do IR and or accurate voltage readings for the cells.
That's because there isn't one. All retail (charger/tester)s use a voltage drop against a known resistor value for their"IR" test. There is no way to properly test for IR/Impedance other than the 4 wire kelvin methode. To get a proper IR and Voltage reading an YR1035+, a RC3563 or equivalent is needed.
Wolf
 

Duchess

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That's because there isn't one. All retail (charger/tester)s use a voltage drop against a known resistor value for their"IR" test. There is no way to properly test for IR/Impedance other than the 4 wire kelvin methode. To get a proper IR and Voltage reading an YR1035+, a RC3563 or equivalent is needed.
Or a HP4263a. 😉
 

Wolf

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Sep 25, 2018
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Or a HP4263a
Yes absolutely a HP4263a or better yet a Keithley DMM7510. For those that have the means to purchases these, more power to them.
The YR1035+ and /or the RC3563 are at a much more reasonable cost being sub $100.00 and quite accurate. ;)
Additionally with the cell holders and especially the RC3563s serial interface, with a little python code and a VB script, the values can be easily machine recorded to eliminate input errors.
Fat finger syndrome and eye fatigue when recording the voltage and IR of 200+ cells at a whack.:p
I have a pretty sophisticated testing procedure
Do share for the benefit of the community as we are all trying to learn.:)
Wolf
 

Wolf

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Sep 25, 2018
Messages
1,561
@Duchess was it something I said?
I wish you luck with your build and we are all looking forward to your progress.
Wolf
 
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