Serious charger problem? Or even battery related...?

[Jimmydoerty]

Hi all, hope you are well.

I recently got my hands on a Bafang ultra e-bike and im loving it so far, however I am not as enthusiastic for the battery and power side of things.

Not to bore everyone with words, heres the issue. When plugging in the charger and turning it on whilst connected, it begins to spin up the cooling fans and then suddenly hits a nasty electrical sounding whirring, almost like a broken fan. I have attached a video below for you to hear. I would like to think this is just a problem with the charger,(being mass produced and chinese), but I feel it may be something more as I am a skeptic , almost seems like the battery is not taking current as it starts but then hits that horrible noise, but I could be wrong.

The charger is a generic-style C300 model battery charger, similar to the one shown below:
https://i.imgur.com/a1vYr7K.png

The battery is a Reention Dorado plus case with 48v LG cells packed by Frey Bikes over in China, a fairly reputable upcoming ebike manufacturer.

I get that this is kind of to be expected with “seemingly generic” chinese chargers, but these are fairly popular, CE and RoHS tested, and more importantly it is only a month old...

If anyone has any insight into this and more so into any good chargers that use a 3-pin DIN connector like this one, I would be very appreciative, as you can imagine I dont want to use this one at all anymore! Thanks all.

[Charger noise video]
https://streamable.com/1kmpr

[3 Pin DIN style connector, not XLR]
https://imgur.com/a/4oqjeRB

 

[obcd]

My first guess would also be a bad fan. A simple test is running it for a very short time with the fan disconnected. If it remains silent like that, you know for sure it's the fan. It shouldn't overheat if you only run it like that for half a minute unless it's a really really bad design.

 

[Jimmydoerty]

My first guess would also be a bad fan. A simple test is running it for a very short time with the fan disconnected. If it remains silent like that, you know for sure it's the fan. It shouldn't overheat if you only run it like that for half a minute unless it's a really really bad design.

Thanks thats a good idea I will give this a go when I am home. Will let you all know results later for purpose of knowledge

 

[Jimmydoerty]

Hi again all.

After further inspection, the fan is OK and this is NOT the problem for anyone searching around.

Thanks to a helpful brain on stackexchange we have (hopefully) narrowed it down to a cause. This appears to be related to noise and interference on my workplaces electrical lines, and that cheaper chargers can miss out filtering components and this may cause issues although not dangerous. (Does have potential)

In enclose the response by Affe.
Even though the design may be CE compliant, the unfortunate reality is that cheap manufacturers will still leave out "unnecessary" circuit components or replace them with fake ones when actually building it. (RoHS just means it's free of lead and mercury etc etc, nothing to do with quality or usability of the electrical design.)

The components that are supposed to filter and reject electromagnetic noise are common victims since they're both expensive and it "normally" works just fine without them.

So if it works fine at home but makes weird noises at work, it seems more likely there's a failing connection in the electrical power system at your work putting a lot of noise on the line, rather than a problem with your charger. (Other than potentially failing to reject an amount of noise that other DC supplies in the building seem to be handling, whether due to a lazy design or corners being cut in assembly.)

 

[HK12K]

Fwiw anyone can print a CE or UL label. If you purchased directly from China those labels are absolutely meaningless.

 

[E-HP]

Regarding fans, even though it wasn't the issue here, is that the bearing are designed to work in a certain orientation, horizontal or vertical. For instance, if you use a horizontal fan, mounted in your computer case, but mount it vertically (or vice versa), it will fail prematurely, starting with a whining/grinding sound, and continue to get worse.

My cheap charger will do that, so I change the orientation until the vibration stops then place it in the right position. At some point it will bug me enough to replace it.

 

[amberwolf]

Regarding fans, even though it wasn't the issue here, is that the bearing are designed to work in a certain orientation, horizontal or vertical.

fwiw, those aren't usually bearings, they're just bushings, and are fairly equally crappy in any orientation.

(though if the bushing is loaded by the fan weight *and* the fan counter-air-movement push, it will wear faster than if it is only loaded by one or the other, and if the weigth and the push counter each other then it will wear slower than usual).

also, in the decades i've used and fixed such things, i haven't seen any markings or labelling on any of these fans that indicate a designed orientation. only arrows showing fan rotation direction and airflow direction (usually molded into the plastic). if they do have a designed orientation, it must be in manufacturer documentation i havent' found.



if a fan has bearings actually meant to be used in a fan, they'll be designed to take side-loading as well as radial, and they will operate just as well in any orientation, with minimal differences in lifespan.

 

[E-HP]

Regarding fans, even though it wasn't the issue here, is that the bearing are designed to work in a certain orientation, horizontal or vertical.

fwiw, those aren't usually bearings, they're just bushings, and are fairly equally crappy in any orientation.

(though if the bushing is loaded by the fan weight *and* the fan counter-air-movement push, it will wear faster than if it is only loaded by one or the other, and if the weigth and the push counter each other then it will wear slower than usual).

I encountered the problem when I built my last desktop PC (does anyone use these anymore?). The case has spaces for four fans, and the one on top is horizontal mounted and forcing air out (your worst case scenario). I had to replace it with a ball bearing fan to keep the noise down shortly after the build; wasn't cheap. Per this article, vertical mounting is best for sleeve, while ball and fluid don't care:

https://www.gamersnexus.net/guides/779-computer-case-fan-bearing-differences

 

[Jimmydoerty]

Fwiw anyone can print a CE or UL label. If you purchased directly from China those labels are absolutely meaningless.

Guessed lol. Take every label with a grain of salt, just depends how reputable the company is and check if they have certifications etc.

But yea it wouldn't surprise me if the company they've outsourced for the chargers has skimped out on filtering components. Now that I was told of this, it makes a lot more sense. Not denying the fans are cheap too! ;But it acts completely different when its on the noisy supply, it immediately hits a nasty problem, whilst on home and clean supplies it has a 3-5 second “initialisation” stage where it waits to turn on then works fine.

Gonna get a cycle satiator from grin tech and splice in the connector I think x-)

 

[Tommm]

Fwiw anyone can print a CE or UL label. If you purchased directly from China those labels are absolutely meaningless.

Gonna get a cycle satiator from grin tech and splice in the connector I think x-)

My Kingpan blew up one day, possibly due to high humidity in the garage.
Bit the bullet, and got satiator 72v. Last charger you will need. 12-103v and rain proof.