Regulable charger

[talgar]

Hi !
have a charger with a potentiometer for changing the current when charging from 0 to 12 A since a year was working well
But since yesterday it fail me....when I want to charge my battery it only want charge at 20A 21A and the potentdont respond...I checked the potentiometer and it works well gradually form 10 to 0

FROM where come the failure? How can I fix it...seems strange since normally this charger don't charge more than 12 A how can it get to 20A now
I guess probably cause of the vibration of my moto when I put in the seat....

 

[99zip99]

Give us a little more information I guess the 220 volt unit to charge at 20 amps. Give us some information about the battery is it led lithium how many volts ???
Do you have a link as where you got the charger ?
Sometimes you can open it up and find a fuse.
Always the cheap easy thing first.

 

[talgar]

The charger it's 110v
My battery 72v

I don't think is the fuse ? Because my charger works and it's charging well ist just I can't regulate well anymore
Well now the potentiometer works I don't know what I did....but it's range is like 3amp to 15amp when it should be 0 to 12 Amp...
It like dcalibrated...maybe something is moving or not making connections properly...but I don't know where exactly

 

[talgar]

This is the one

20S 72V Li-ion 84V 20AH-120AH Lithium Battery Smart Charger Adjustable 3A-12A | eBay

Suit for 20AH to 120AH Li battery、 you can adjust the current 2A to 12A. output current : 2A to 12A you can adjust. Overheating protection. Overcurrent protection. Reverse connect protection. Short circuit protection.

www.ebay.com

 

[99zip99]

What kind of meter do you have that's telling you 3amp and 12 amp. Then you talk about 20 amp in your first post ?
A lot of times a a charger at 10 amps can charge it 11 or 12 amps. Is Chinese it's not written in stone.
So it's working it's just charging at 12 amps and you can adjust it down to 3 amp ?
Have you first contacted the supplier it's always good to buy those with PayPal or some other guaranteed.

I had trouble with the charger like that not built as well about 6 years ago and PayPal covered the money.

 

[talgar]

This charger isn't newly bought it have one year with me...I keep it in the seat of my scooter because I don't like to drive without charger...you never know...but of course vibration is what damaged my charger...no guarantee for that

I just try to found where is the problem to fix it...I know that the display have 2 o 3 Amp difference with what the battery really get
Every Amp I mentioned are from the Jk Bms indications on the app
Yesterday somehow it started to work again between 3 to 12 Amp...almost like normal because normally the minimum can be set a 0
But today again started to act crazy ...give me 20amp real From the Jk app and my bms just turn off the battery for protecting
Impossible to set it down the potentiometer don't respond but it works on a multimeter
Did nothing since yesterday don't know why it changed by itself?
Don't know what to do...
Think about unweld parts and set it back again?

 

[99zip99]

You should have a second volt and amp meter to verify. There cheap .But the BMS off as an indicator.
You can open it up and my first guess would be the parameter switch. But there again you would need a meter that would able to handle a hundred amps in theory.
110 x 20amps = 2,200 watts should blow your fuse box if 15 amp. Maybe a 20amp line ?
Being cheap I have six plug extension oh a surge protector that are fused easy at 15 - 12 amp see if it'll blow that fuse. Ez.
Plus what are the exact cells model number name in your battery.. Battery app. ? You have a BT BMS what amp ? I mean do you have a link ?
Maybe you're right that thing shouldn't be on your bike or scooter or motorcycle what is it ?

 

[talgar]

The Bms app is the best multimeter it say the excat volt and Amp in my battery
My charger give 12 Amp at 84v...i guess is less at 110v ... no enought to blow house fuse even at 20amp
My cells are 18650 lishen 2500mah
My Bms is JK bms
Is a motorecycle...i know i should bring it on the seat...been couple of chargers that die now...but really i cant travel long distance without charger...you never know have to bring it...

 

[talgar]

Were is the parameter switch?
I only found a blue with a tiny potentiometer but this calibrate only which voltage the charger stop to charge

 

[99zip99]

Be careful turning the blue parameter with the brass screw I've turned them before and I turn it too much and I blew a charger. The one I did was for voltage.
You said you can charge at 3 amps to 15 amps is that a digital switch or do you turn it like a knob with your finger ?.
Is the knob that's black you turn it to the right it increases average
Talk to text figured oute turn it down it decrease ampage.
I don't buy those anymore for travel I have one from grin ebike 72 volt 5 amp.
For my house at 3 meanwhiles put together for 84 volts 15 amp. That's the most my garage circuit could take.
Having a second amp meter and voltmeter is to test the quality of your BMS and your bms's amp rating that's how you test things you have something else to test with.

 

[talgar]

I turned it just a little and my charger stopped to charge and the green light show full charge when i was at 79v so guess is just for set up the limit voltage

The potentiometer for regilate the current is black knob normally it do the job between 0 and 12amp but since yesterday it was between 3 to 12 or 15amp depend...the Amp on the ampmeter kind of cycle and dont really stay fix like circling 3.9 toto 4,1 to 4.2 for example ...normally should not do that
And sometime got crazy and stuck to 20amp qnd i cannot lower it with the knob

So You have 3 charger that you conect to your battery to get 15 Amp?

 

[99zip99]

Ok I'll bite three 24 volt meanwells turned up to 27volt each as they must be each charger the same voltage and it adds up to 83.6v . After full charge mine don't have a latching and will only stay at 83.6 to unplug it but charging at 15 amps 20 ah battery takes 50 minutes.
I think they are $30 a piece but if I tap into one is 27 volts for 24 volt battery and I charge 14s at the 55 volt level, two chargers I'll show you a picture tomorrow.
The reason I use them because they were cheap hospital grade and very durable. As I have boxes of chargers.

Most chargers aren't going to be able to be carried on a bike the one I recommend is made me carried on the bike charges at 5 amps for 72 volt. Waterproof it probably runs on 110 or 220 it's from. E-bikes ca.