RESOLVED: YZpower-450 troubles?

[Tawpie]

I hope this isn't thread jacking because it doesn't involve a Veteran, if it is perhaps a mod can move it? I'm putting it here because it's the only thing that comes up in a forum search for YZPOWER-450... anyhow.

I got one, it's a rev 03, 84V 5A (fixed current output) with the Lenovo KingSong connector and I'm wondering if it's "not quite right". Yeah, it was an Amazon open box so I am being extra vigilant. But it seems to work fine on my KS16X *except* it shuts off, or something shuts off, before the charge cycle is complete. The last voltage recorded by EUCWorld before the charger clicked off (fans suddenly off, LED is green) is 84.13 and I'm not sure if the charger decided it was finished or the wheel decided it had had enough. The wheel didn't do it's usual end of charge 6 beep thing so I do think the charger is what shut down.

That said, unplugging and replugging the charger doesn't kick the wheel fan+bluetooth on, so I also think the wheel now believes it's charged enough (even at 83.6V)... it does turn on and balance and doesn't smell like magic smoke got out, so I don't think I suffered the same fate as some Shermans have. This is the second time I've charged with this unit, the first time I wasn't paying attention and happened to notice the charger was off... wasn't logging data either.

On the stock XVE126-8400150 (84V 1.5A) charger, charging continues until the wheel beeps 6 times and after disconnection the reported voltage settles at little high at 84.5V. On the YZPOWER, we never made it that far.

Perhaps @YZPOWER can say if this looks normal or should I return the charger to Amazon? Normal or not, it's pretty clear that this particular unit is only good for bulk filling and must be stopped early, removed, and the charge cycle+balance completed with the stock unit. To my eyes, it looks like the charger charged to 84.1 volts and stopped—it did not stay in the CV phase and hold until the current dropped to a "low enough" level... it's either not really a charger for Li Ion, or it's broken.

Do others with YZPOWER-450s see this shutdown behavior or do your chargers get your batteries to full voltage?

Thx!

Edited March 6, 2021 by Tawpie
make the chart a little clearer via axis adjustments

[Chriull]

3 hours ago, Tawpie said:

The wheel didn't do it's usual end of charge 6 beep thing so I do think the charger is what shut down.

One "wheel sutdown" should be directly by the BMS in case of single cell overvoltage - there could be nothing the wheel notices so it could beep or whatever.

But i'd see no reason for this from the numbers you mention - but the y-axis on your second graph is missing...

The other ?possible chatge cut-off? reason would be too high charge current - but with 1.5 A it should be well within limits.

Just seen - the charger should be a 5A fixed current charger?!  The graph shows current dropping from 2.5 to around 1.5A - so already well within the CV stage!

So this shows just a very partial charge in contrast to the second graph?

[Chriull]

4 hours ago, Tawpie said:

I hope this isn't thread jacking because it doesn't involve a Veteran,

Just split this off the other topic since it has nothing to do with veteran but was in the veteran subforum.

And yes - this seems quite a good example for thread jacking

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if it is perhaps a mod can move it? I'm putting it here because it's the only thing that comes up in a forum search for YZPOWER-450... anyhow.

If everyone puts his post to some topic he found with some keyword this would be a very interesting forum...

You can everytime start an own new topic for posts, especially if they contain/start a new topic!

 

[Tawpie]

7 hours ago, Chriull said:

You can everytime start an own new topic for posts, especially if they contain/start a new topic!

Thank you for moving this and for the counsel. Some forums lean more toward “this key phrase was in that thread over there already, did you even bother to search first?” so I wasn’t sure. But now I am!

Took the wheel out for a short spin and it’s back on the stock charger to balance and collect data. The second chart doesn’t have a Y axis, it’s an older wheellog reader but I wanted to show that the YZPOWER did start at 5A and did act like it entered CV, it just decided to shut down at 84.1V.

If this unit isn’t “broken” it might be a warning to others to verify what’s really happening with their YZPOWER “chargers”. This one doesn’t appear to follow the correct protocol even though the wheel says it’s fully charged.

Edited March 6, 2021 by Tawpie

[Chriull]

39 minutes ago, Tawpie said:

The second chart doesn’t have a Y axis, it’s an older wheellog reader but I wanted to show that the YZPOWER did start at 5A

Ah ok - both charts are with the yzpower!

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and did act like it entered CV, it just decided to shut down at 84.1V.

It did not only act like but i was really and solidly in the CV stage!

Seems like your batteries have some imbalance and bms shuts off due to cell overvoltage...

If you continue chatgimg with your stock charger it finishes the cv stage?

You have a log of such a successfull xhatge directly after a stopped yzpower charge?

Quote

If this unit isn’t “broken” it might be a warning to others to verify what’s really happening with their YZPOWER “chargers”. This one doesn’t appear to follow the correct protocol even though the wheel says it’s fully charged.

Imho not enough facts here to say anythimg in regard of the charger.

 

Btw - in https://forum.electricunicycle.org/topic/22109-passive-balancing-a-simulation/

is a simulation of such a cut off charge:

It's the 5th charge cycle - if one would charge here with less current so cell overvoltage protection is not activated and charge could succeed like in the 6th cycle...

[Tawpie]

7 hours ago, Chriull said:

Seems like your batteries have some imbalance and bms shuts off due to cell overvoltage...

This is starting to smell like the correct answer. On the stock XVE 1.5A charger, charging also stopped early: 84.02V, -1.3A was the last reading the wheel sent to EUCWorld before bluetooth shut down. 2 days ago on the stock charger it charged to its usual 84.5V and terminated with the 6 beeps (indicative of completion of balance, or so I'm led to believe) so whatever has changed did so suddenly. I wish I had a video-worthy wreck to blame it on, but can only report the standard flop-on-its-side-cuz-I-missed-the-handle events.

So, when I get back to the tools, it'll be open the wheel and charge each pack separately to see which one is tripping early. This is a KS16XS, but an extra genuine KS pack was added about 3 weeks ago so it's possible the new pack is to blame. It's also possible the original pack is to blame, KS's battery warranty is 6 months and it's been six months and 2 days since I received the wheel. I guess opening the wheel is good anyway, I have replacement hex head shell screws this time.

[Chriull]

8 hours ago, Tawpie said:

So, when I get back to the tools, it'll be open the wheel and charge each pack separately to see which one is tripping early. This is a KS16XS, but an extra genuine KS pack was added about 3 weeks ago so it's possible the new pack is to blame.

Unprobable but definitely worth checking as the new pack still should have warranty!

[Tawpie]

Got it on the bench, tried to charge with the stock charger and the wheel shutdown at ~84V. Unplugged the new battery, reconnected to the stock charger and the charge ran the full cycle to 84.5V (it's always read that, I think it's measurement error), beeped 6 times and left the BT on. Unplugged and power cycled to avoid phantom drain. Open circuit voltage on the new pack after the premature charge shutdown is 82.1V.

So I'm pointing fingers at the new pack (thanks @Chriull). I'll wait until the supplier gets back to me before putting the cover back on but won't be reconnecting the new pack since the two packs are now at very different voltages. I suppose it'd be instructive to disconnect the old pack and see if the new pack gets the complete charge cycle when it's charged all by itself—one could imagine there's something wrong that isn't either battery's fault. Perhaps I'll try that tomorrow. But I sort of want to see what the supplier comes back with before messing around too much. And I'm a hair nervous charging a pack that may be struggling.

Anyway, I'm considerably less certain this is a problem with the YZPOWER charger (although the YZPOWER device hasn't been given a chance to prove it can stay on for the full charge cycle yet) and if it turns out to that the charger is unrelated, I will attempt to change the thread's title so as not to falsely alarm people!

[Tawpie]

Update: new control board in transit, the diagnosis is that the current board is reading the voltage too high thus causing early charge cycle termination. Guess I have a nice weekend project ahead of me, going to be getting intimate with my wheel’s deepest recesses... I hope I don’t bust it.

The YZPOWER will probably be heading back to Amazon (again, it was a warehouse item when I bought it). It may not be related, but the wheel was happy with the slow charger. I’m not brave enough to try the YZPOWER again... I probably should open it up and verify the no load output voltage before sending it back, I do want a fast charger but dang they’re expensive.

Edited March 11, 2021 by Tawpie

[Tawpie]

Update: new control board installed, it reads the battery voltage more accurately (not 84.5V at full charge, now 83.8V) but the new battery still shut down the control board at about 82.5V. Now amassing packing material to ship the new battery back (recycle truck came this week and took all the used packing material... great.). YZPOWER charger was returned to Amazon, I don't dare connect anything other than the stock slow charger until this gets straightened out.

[Tawpie]

kk. I'm closing my book on this one, I don't know if the charger had anything to do with it but...

1. the charger was returned because I didn't trust it: my issues started the first time I used it AND it had already been returned by somebody else (it was an Amazon warehouse item).
2. after a control board change did not 'fix' the early charge cutoff, I believe one of the packs was signaling a problem and driving the charge stop connection. This caused the entire control board to power off, something that is not seen during 'normal' charging... supporting argument for "normal charge cycle includes not turning off" is the 'phantom drain' that KS wheels are known for
3. I replaced one of the battery packs (the new one that had been in operation for a month and had been working just fine until I used the YZ450)
4. the wheel with the new battery and new control board, but now on the stock charger, charges to an EUCW indicated 83.9V and the control board stays powered on.
5. the only thing that's different now is that I haven't heard the 6 slow beeps that I have interpreted as "balance complete" based on tribal lore. Those beeps may just be the idle shutdown warning and I have no idea what they were supposed to mean—maybe not hearing them now isn't a big deal. I don't know but I'm not going to worry about it

So my conclusions:

1. early charge cutoff was due to a fault in the second battery pack and the pack's safety mechanism (charge stop) worked as it was supposed to
2. the open circuit voltage of the second battery pack after it signaled charge stop (assuming that's what was happening) measured 82.4V so the pack as a whole wasn't over charged
3. I have no idea how the second battery pack developed the fault, but since it suffered some visible damage during shipment it could well have finally failed
4. I have no reason to blame the YZPower charger for the failure of the second battery pack other than pure circumstantial coincidence, but am suddenly very leery of YZ's 450 because of other reports of problems that were also circumstantially coincident with use of the YZ-450
5. my stock control board reports the battery voltage 0.6V "higher" (84.5V at full charge) than the replacement control board (83.9 at full charge)—I have no idea if that matters to the firmware
6. I'm on the hunt for a 5A charger for KS that isn't YZ and I absolutely HATE how much I'm going to have to pay—the "you get what you pay for" rule really blows chunks sometimes.

[Flying W]

Thanks for the update! 

My mcm5 had a board that was faulty in the very beginning. It reported 84 even when full (it groaned at slow speed, something in the firmware unrelated to charging).

My replacement board reports 82.7 on EUC world, however when I measure with my meter it's at 84.3, within the tolloramce range of accuracy. I think the boards vary a bit in their reporting. 

I've since put almost 4k miles on the replacement board and my batteries still charge to 84.2 on my meter, the board is reporting 82.7 to EUC world. 

It's always s good idea if EUC world shows something odd to check with a meter to make sure. 

My RS has a YZ 450 and I'm always a little worried about it, but I don't want to fork out for a good charger right now. So far it charges fine though, but the fan makes noise for the first 5min when charging.