Master charge max at 133V

[Gabriz81]

Good morning everyone! I finally managed to buy myself a master and...... I already have some problems! apart from the fact that there are 2 stripped screws in the battery packs (not the screws, but the aluminum of the frame...), I saw on the first charge it was at 131,9 and then i reconnect it and that it doesn't go beyond 133V. I checked the charger and its output is 134.5V, so it's ok. My master has the latest charge board (2022-02-28). The incredible thing (for me), is that the seller says that he talked to the BEGODE engineer, who said that a little tolerance is normal. What do you think about it?

[Cerbera]

21 minutes ago, Gabriz81 said:

What do you think about it?

It's fine. Mine only goes up to 133.9, and falls back to around 133.2 by the next day if I leave it unplugged. Begode engineer is right - there will be some tolerance up there, but as long it is under a volt low it doesn't affect range noticeably and isn't anything to worry about. Also, just the act of powering on the EUC after a charge will drop a couple of 1/10s of a volt off almost immediately.

Edited March 6, 2023 by Cerbera

[Rawnei]

By now it's difficult to say what is "normal" on this wheel but only charging to 133.0v (?) doesn't sound great to me.

I've left my Master untouched for a couple of days now since charging now (already down to 131v-ish) and will leave it some more and see if it stops draining at some point, S22 is up and running again with SKF bearings and that's my favorite anyway so I have a wheel I can ride and let this sit for a while and monitor it.

[Gabriz81]

18 minutes ago, Cerbera said:

It's fine. Mine only goes up to 133.9, and falls back to around 133.2 by the next day if I leave it unplugged. Begode engineer is right - there will be some tolerance up there, but as long it is under a volt low it doesn't affect range noticeably and isn't anything to worry about. Also, just the act of powering on the EUC after a charge will drop a couple of 1/10s of a volt off almost immediately.

yes when i power on the master it drop immediately 0,1V. I'm not a ingeneer, but when i buy a wheel, i ever controlled if it charge at max, for ex. the Rs for me must to been 100.8 at full charge, if not, ever for me, must to have any problem "of battery". when it had 100.6 i worried and have controlled the batteries singularly for check it...and Rs was 2 years old. I know it, maybe in my error. I'm just disappointed because I expected that master charge at least 134.x like the others. 1.4V of tolerance are a too many for me....

....but surely you will have more experience than me. Thank you

[Gabriz81]

24 minutes ago, Rawnei said:

By now it's difficult to say what is "normal" on this wheel but only charging to 133.0v (?) doesn't sound great to me.

I've left my Master untouched for a couple of days now since charging now (already down to 131v-ish) and will leave it some more and see if it stops draining at some point, S22 is up and running again with SKF bearings and that's my favorite anyway so I have a wheel I can ride and let this sit for a while and monitor it.

yes. It doesn't sound good to me either, I just paid for have it new last week. You have to think I haven't even reached the next step...check the battery drain. 

I wonder what can block the charger at 133V, maybe it could be the charging board?

[Rawnei]

6 minutes ago, Gabriz81 said:

yes. It doesn't sound good to me either, I just paid for have it new last week. You have to think I haven't even reached the next step...check the battery drain. 

I wonder what can block the charger at 133V, maybe it could be the charging board?

Most likely the BMS on one of the packs cutting the charge, perhaps they are not balanced? Could be worth it to check all 4 packs with a multimeter and see what they're at.

[Gabriz81]

4 minutes ago, Rawnei said:

Most likely the BMS on one of the packs cutting the charge, perhaps they are not balanced? Could be worth it to check all 4 packs with a multimeter and see what they're at.

yes i thinked it....next step: try to discharge the master using it (I'm using it less in these rainy days), recharge it to max and then check singularly the all 4 packs with multimeter. 

[supercurio]

1 hour ago, Gabriz81 said:

I saw on the first charge it was at 131,9 and then i reconnect it and that it doesn't go beyond 133V. I checked the charger and its output is 134.5V, so it's ok.

It's good you noticed that.

Based on your description, it is not related to the charge board issue. Please create a separate thread so we can help you troubleshoot it there.
I think it could be either something innocuous that could sort itself out, or something dangerous that demand immediate attention hence the need for extra steps looking into it.

[Gabriz81]

3 minutes ago, supercurio said:

It's good you noticed that.

Based on your description, it is not related to the charge board issue. Please create a separate thread so we can help you troubleshoot it there.
I think it could be either something innocuous that could sort itself out, or something dangerous that demand immediate attention hence the need for extra steps looking into it.

ok i will do it

[Gabriz81]

Good morning everyone! I finally managed to buy myself a master and...... I already have some problems! apart from the fact that there are 2 stripped screws in the battery packs (not the screws, but the aluminum of the frame...), I saw on the first charge it was at 131,9 and then i reconnect it and that it doesn't go beyond 133V. I checked the charger and its output is 134.5V, so it's ok. My master has the latest charge board (2022-02-28). The incredible thing (for me), is that the seller says that he talked to the BEGODE engineer, who said that a little tolerance is normal. For a little tolerance is 0.1/0.3.. What do you think about it? 

Anyone else with this problem? Is a problem?

[Chriull]

@Gabriz81 - i split the whole discussion off to this new topic, so the discussion are not lost!

 

[Chriull]

2 hours ago, Gabriz81 said:

reconnect it and that it doesn't go beyond 133V. I checked the charger and its output is 134.5V,

Deviations of up to 1% between to voltage meters are nothing uncommon!

If both voltages are measured with the same multimeter i'd go with 

On 3/6/2023 at 8:13 PM, Rawnei said:

Most likely the BMS on one of the packs cutting the charge, perhaps they are not balanced? Could be worth it to check all 4 packs with a multimeter and see what they're at.

 

[supercurio]

Thanks @Chriull for the split!

@Gabriz81 would you be able to check the voltages, with the same multimeter of:

• charger
• packs 1 to 4 individually

Then compare with the voltmeter of the wheel with all packs connected together, as reported to apps.

As a starting point 😌

[Gabriz81]

Yes sure, i have just to diacharge my master, but in these days i don't using it

[Chriull]

1 hour ago, Gabriz81 said:

Yes sure, i have just to diacharge my master, 

I can't follow why you need to discharge before measuring the battery voltage vs charger voltage with the multimeter?

[supercurio]

@Gabriz81 checking voltages as-is to see how things are, and if things looks reasonably okay and safe, the next step would be to check the same voltages right after the end of a charge.

[Gabriz81]

8 hours ago, Chriull said:

I can't follow why you need to discharge before measuring the battery voltage vs charger voltage with the multimeter?

Because i want to measure the battery voltage after i recharge it at the 100%. Now is at 90%

[Gabriz81]

17 hours ago, supercurio said:

@Gabriz81 checking voltages as-is to see how things are, and if things looks reasonably okay and safe, the next step would be to check the same voltages right after the end of a charge.

do you mean to measure the voltage of the single pack now wich "the total" is at 90%?

[supercurio]

Yes it'll show if there's a delta in voltage between the packs, and give an idea of a difference between what your multimeter reads and the wheel's mainboard 

[Chriull]

And if you have some power meter (wlan plug, etc) you can watch while charging if power consumption stops abruptly (downto charger idle dissipated power) or just decreases continously.

In the first case there is a bms cut off due to single cell overvoltage in one pack. Which is most likely caused by some cell imbalance.

With EUC World and the right plug one can log charging. ( shelly plug s and the discontinued tplink hs110 are supported as ?premium feature?)

One could also try to charge again and again with about an hour break once the green led shows. If the cause is an unbalanced pack final charge voltage should slowly but steadily rise with each charge cycle.

(Again no discharge needed inbetween - just this about an hour to let the bleeding resistor do his work)

Edited March 9, 2023 by Chriull

[Gabriz81]

On 3/8/2023 at 4:59 PM, supercurio said:

@Gabriz81 checking voltages as-is to see how things are, and if things looks reasonably okay and safe, the next step would be to check the same voltages right after the end of a charge.

i have measured the Voltage of the batteries:

% EUC W. : 89%  V:128,1

checked on the master from board: 129.2/3 V

single pack batteries:

ant. sx 64,5V    ant. dx 64,7V

post. sx 64,5V  post. dx 64,7V

[supercurio]

@Gabriz81 okay so good news so far!

• Your packs in series are fairly well balanced, nice
• (assuming your multimeter is accurate which it might not) the mainboard indicates 1.1V lower

So when going back to the original problem description, and the charger outputting 134.5V (measured with the multimeter), the wheel charging indicating 133V once fully charged seems fine 👍

You can measure the voltages again with the multimeter after a full charge if you'd like to double-check.

[Gabriz81]

7 minutes ago, supercurio said:

@Gabriz81 okay so good news so far!

• Your packs in series are fairly well balanced, nice
• (assuming your multimeter is accurate which it might not) the mainboard indicates 1.1V lower

So when going back to the original problem description, and the charger outputting 134.5V (measured with the multimeter), the wheel charging indicating 133V once fully charged seems fine 👍

You can measure the voltages again with the multimeter after a full charge if you'd like to double-check.

yeah i think so too! if the difference remain at full charge, is the mainboard that read bad the voltage! I hope is like this!

Now, i discharge the master using it and then i check the voltage at full charge....if is like we think, i can request maybe a new mainboard more precise at the seller.............

.......stay tuned!  thanx 

[supercurio]

Just now, Gabriz81 said:

yeah i think so too! if the difference remain at full charge, is the mainboard that read bad the voltage! I hope is like this!

Sounds good

Just now, Gabriz81 said:

Now, i discharge the master using it and then i check the voltage at full charge....if is like we think, i can request maybe a new mainboard more precise at the seller.............

Fortunately 1.1-1.2V is not a super large gap in practice for our EUC use case.

Of course it will reduce the usable range a little bit before tiltback, but not that much since the voltage drops quickly at the end of the discharge curve. On the plus side you have a bit higher safety margin than a standard Master.
LeaperKim here has been smarter by allowing to recalibrate the internal voltmeter, which solves this completely.

As software solution to this hardware calibration issue, you could also flash a custom Master firmware which set the tiltback voltage a bit lower than stock, and it'll solve the problem entirely without hardware change.

[Gabriz81]

9 minutes ago, supercurio said:

Sounds good

Fortunately 1.1-1.2V is not a super large gap in practice for our EUC use case.

Of course it will reduce the usable range a little bit before tiltback, but not that much since the voltage drops quickly at the end of the discharge curve. On the plus side you have a bit higher safety margin than a standard Master.
LeaperKim here has been smarter by allowing to recalibrate the internal voltmeter, which solves this completely.

As software solution to this hardware calibration issue, you could also flash a custom Master firmware which set the tiltback voltage a bit lower than stock, and it'll solve the problem entirely without hardware change.

Leaperkim is more expensive than master...i need to see in what it translate 1.1 V....2-3km? 5? let will see now we can wait for 2nd step