[(Resolved)] Battery Problem

[Gary786]

Hey guys! Hope you all are doing fine. I need help with my battery.. I accidently inserted the positive probe of my multimeter in AMPS section instead of volts to check the voltage. Now my battery isn't working nor it's getting charged. I could only hear a noise and then it stopped working.

Now when I keep the battery pack for charging I can see 54.8V and the bike works. But as soon as I unplug the charger it shows zero volts. Can anyone here help me understand how can I fix this? Please help!

 

[Chalo]

You probably zapped the BMS. Dead short circuit is a good way to do that.

 

[Gary786]

You probably zapped the BMS. Dead short circuit is a good way to do that.

Is replacement the only solution?

 

[Chalo]

You probably zapped the BMS. Dead short circuit is a good way to do that.

Is replacement the only solution?

You'll have to replace the BMS if it's dead. But first, check for a burned fuse that might be the only problem. Some packs have them and some don't. If you're lucky, replacing a fuse will fix your pack.

If that's not it, then check all your cell voltages to see if the BMS is working correctly to prevent you from using the battery in a fault condition.

If there isn't a fuse (or if the fuse isn't burned), and if the cell voltages all check out (all the same, none above 4.25 or less than 3), then you can proceed with replacing the BMS. If the terminal you were probing is badly damaged by an arc, you might need to replace or repair that too.

 

[Gary786]

You probably zapped the BMS. Dead short circuit is a good way to do that.

Is replacement the only solution?

You'll have to replace the BMS if it's dead. But first, check for a burned fuse that might be the only problem. Some packs have them and some don't. If you're lucky, replacing a fuse will fix your pack.

If that's not it, then check all your cell voltages to see if the BMS is working correctly to prevent you from using the battery in a fault condition.

If there isn't a fuse (or if the fuse isn't burned), and if the cell voltages all check out (all the same, none above 4.25 or less than 3), then you can proceed with replacing the BMS. If the terminal you were probing is badly damaged by an arc, you might need to replace or repair that too.

Thanks for replying..

I will check all of that.. I'm so paranoid and scared hope the battery don't blow up on my face

 

[TommyCat]

Did the exact same thing shortly after receiving my battery…

Luckily mine reset with the on/off switch being cycled after a few nervous minuets.

If no power switch, or a blown fuse, a method called “jump starting” may be needed…
https://lunacycle.com/jumping-your-luna-shark-battery-pack/

Lastly, disconnecting and reconnecting the BMS’s wiring connector as a last resort may work.

Fingers crossed,
T.C.

 

[Comrade]

Did the fuse in the multimeter blow? Or was it a Chinese special multimeter?

 

[Gary786]

You probably zapped the BMS. Dead short circuit is a good way to do that.

Is replacement the only solution?

You'll have to replace the BMS if it's dead. But first, check for a burned fuse that might be the only problem. Some packs have them and some don't. If you're lucky, replacing a fuse will fix your pack.

If that's not it, then check all your cell voltages to see if the BMS is working correctly to prevent you from using the battery in a fault condition.

If there isn't a fuse (or if the fuse isn't burned), and if the cell voltages all check out (all the same, none above 4.25 or less than 3), then you can proceed with replacing the BMS. If the terminal you were probing is badly damaged by an arc, you might need to replace or repair that too.

That's the BMS in my battery.. Dont no which one is this.. Can you tell me a suitable replacement for this one?

 

[Chalo]

It seems I can never get a direct replacement for any original equipment BMS that craps out. You'd think that at least once in a while, the plug for the old BMS would match the new one, but that seems to be in violation of the rules that govern these things.

So the bad news is, most likely you have to splice 13 or 14 cell sense wires one at a time to a new plug, then solder in the main battery negative, output negative, and charge negative leads. That is, you'll have to do all this if a new BMS is required.

You could try contacting the battery seller to see if they'll supply a replacement BMS. When I've done that, they sent one that wasn't the same and I had to do the wire splicing thing anyway.

Get a BMS (I use eBay usually) that is for the same cell voltage and series cell count as your battery, and supports at least as much maximum current as your bike's controller uses.

I can't make out much useful information from your old BMS label, but it says 60-100A. Why the range, I don't know. But the important thing is that your BMS is rated for (ideally) more juice than your controller needs.

 

[AZeBikeGuy]

Did the fuse in the multimeter blow? Or was it a Chinese special multimeter?

Most meters have an unfused 10A range input in addition to a fused lower range input

 

[Comrade]

Most meters have an unfused 10A range input

Maybe most meters that should have never been available for sale. :lol:

 

[AZeBikeGuy]

Most meters have an unfused 10A range input

Maybe most meters that should have never been available for sale. :lol:

Perhaps I should have said "most meters the users on this forum use have an unfused 10A range input

I would bet most folks on this forum that aren't doing electronics professionally and have a meter with a 10A input, the input won't be fused... nature of the beast with cheap meters

And while I may be a DVM connoisseur, I'm certainly not a snob - the cheap ones not only have their place but are very, very useful since you can have a lot of them so they're always handy

I've got quite a few DVM's and the higher end ones are all fused on the high current input but the other <$20-$30 ones I'm pretty sure are all unfused... I have about the same number of both and the cheap ones are good bang around, disposable meters... I have a nice bench meter that gets calibrated and I use it to compare the others to... but the cheap ones likely get used more than the good ones since they are usually at hand and "good enough"...

I'd rather see people have a $20-$30 meter than not have one at all... they should understand their limits though, especially accuracy and fusing (or lack thereof)... When I see people say they adjusted their battery charger but used a cheap meter to do it I always cringe...

 

[E-HP]

Most meters have an unfused 10A range input

Maybe most meters that should have never been available for sale. :lol:

I guess it costs money to protect the unit from operator error.

 

[Gary786]

It seems I can never get a direct replacement for any original equipment BMS that craps out. You'd think that at least once in a while, the plug for the old BMS would match the new one, but that seems to be in violation of the rules that govern these things.

So the bad news is, most likely you have to splice 13 or 14 cell sense wires one at a time to a new plug, then solder in the main battery negative, output negative, and charge negative leads. That is, you'll have to do all this if a new BMS is required.

You could try contacting the battery seller to see if they'll supply a replacement BMS. When I've done that, they sent one that wasn't the same and I had to do the wire splicing thing anyway.

Get a BMS (I use eBay usually) that is for the same cell voltage and series cell count as your battery, and supports at least as much maximum current as your bike's controller uses.

I can't make out much useful information from your old BMS label, but it says 60-100A. Why the range, I don't know. But the important thing is that your BMS is rated for (ideally) more juice than your controller needs.

Guys i have recieved a new bms sometime back.. My old BMS only has one indicator (P-) on it.. Can someone tell me how to identify B- and C- without opening up the whole battery?

 

[Gary786]

Attaching few pictures and screenshot.. I'm totally confused.. Please help

 

[Gary786]

It was a blown fuse inside hidden.. But thanks for all the efforts guys

 

[Chalo]

It was a blown fuse inside hidden.. But thanks for all the efforts guys

That's good news!

 

[E-HP]

It was a blown fuse inside hidden.. But thanks for all the efforts guys

If you have time, it would be nice to see a pic of the solution. That might help future members that may have a similar issue in the future. Thanks for the follow up.

 

[Gary786]

It was a blown fuse inside hidden.. But thanks for all the efforts guys

If you have time, it would be nice to see a pic of the solution. That might help future members that may have a similar issue in the future. Thanks for the follow up.

The fuse below the ignition switch was blown.. Everything else was all OK.. There was a lot of learning.. I'm sure I won't do this mistake again..

This forum is very helpful..

You guys are awesome

 

[calab]

Where was the fuse hidden inside the battery covering or between the daughterboards or casement of the bms.

 

[amberwolf]

Where was the fuse hidden inside the battery covering or between the daughterboards or casement of the bms. 2 layer bms.jpg

The fuse below the ignition switch was blown..

(pics of it are attached to his post; it appears to be the switch inside the battery case (not inside the battery or BMS itself) but I can't tell for sure)