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Old 06-29-2020, 01:53 PM   #1
Cobblers
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Default 29.4v Chinese li-ion charger

This charger arrived today for my ebike.

I had to wire a new bms into the battery pack first as the original giant bms wouldn't work with a generic charger.

Anyhow I plugged in the charger after connecting the battery and it charged fine.

I noticed that once it finished charging the the status led on the charger stayed lit green even when the mains power was disconnected.

I connected it back the mains and there was a loud bang. Charger has blown up

I've contacted the seller on ebay, I just want your thoughts on the charger in general and wether it would be worth accepting a replacement if the seller offers
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Old 06-29-2020, 05:07 PM   #2
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Default Re: 29.4v Chinese li-ion charger

This is the problem with switching power supply that are made in China there quality controls are hit and miss

I do not like chargers that do what you described when you unplug it that the charge status indicator stays light like that
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Old 06-29-2020, 08:48 PM   #3
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Default Re: 29.4v Chinese li-ion charger

Looks like the solder blobs caused a short, WTF!
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Old 06-29-2020, 11:57 PM   #4
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Default Re: 29.4v Chinese li-ion charger

Man! what kind of fuse did they installed in F1 location?
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Old 06-30-2020, 02:12 AM   #5
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Default Re: 29.4v Chinese li-ion charger

get your money back and feel lucky your house didn't burn down .
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Old 06-30-2020, 08:10 AM   #6
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Default Re: 29.4v Chinese li-ion charger

Quote:
Originally Posted by budm View Post
Man! what kind of fuse did they installed in F1 location?
"Improved" version of Apple fuse
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Old 06-30-2020, 09:11 AM   #7
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Default Re: 29.4v Chinese li-ion charger

Quote:
Originally Posted by Spider1211 View Post
"Improved" version of Apple fuse
apple fuses are the best, they last decades.
not like those cheap chinese shit that burn out as soon as you reach the rated current!
/sarc

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Old 06-30-2020, 09:15 AM   #8
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Default Re: 29.4v Chinese li-ion charger

i see what happened,
the board is designed for a box-fuse and they fitted a tiny glass fuse.
combined with a shorted bridge rectifier (happens),
the fuse couldnt break the circuit fast enough and it arc'd under the board.
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Old 06-30-2020, 01:12 PM   #9
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Default Re: 29.4v Chinese li-ion charger

sigh... more chinese noob phails yet again...
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Old 06-30-2020, 01:26 PM   #10
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Default Re: 29.4v Chinese li-ion charger

I would get the money back and buy something better.
BTW, can see the enclosure so we can see the make and model and the markings?
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Old 06-30-2020, 02:13 PM   #11
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Default Re: 29.4v Chinese li-ion charger

Quote:
Originally Posted by budm View Post
I would get the money back and buy something better.
BTW, can see the enclosure so we can see the make and model and the markings?

I second this
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