Question Problem with a pms

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Hello,

I have a problem with my pms. The wii works when plugged in and the charging works too.
If I test it without load I have 8.33V on the output fully charged, bug as soon as I put a load on it(turning on the wii), the voltage drops to 4.2V. The wii is working (I have the sound of it). No display, but it's not turning on because it needs 5V and it's not enough.

I guess that maybe it has something to do with the pms's output IC but I don't know.
Is it fixable or do I need a new one?

That is the PMS model I use: https://www.aliexpress.com/item/32948772265.html?spm=a2g0s.9042311.0.0.27424c4dupkLtm

Best,

Emetsys
 

Wesk

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You linked a Battery management system, how exactly are you powering individual Wii voltages?

[EDIT]

Judging by your post history you're using PAM80808080808080808WAH's, in that case you'll need a boost circuit to get 5v as your batteries will only put out 4.2V MAX, and that will quickly drop to sub 4V.
 
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Stitches

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Hello,

I have a problem with my pms. The wii works when plugged in and the charging works too.
If I test it without load I have 8.33V on the output fully charged, bug as soon as I put a load on it(turning on the wii), the voltage drops to 4.2V. The wii is working (I have the sound of it). No display, but it's not turning on because it needs 5V and it's not enough.

I guess that maybe it has something to do with the pms's output IC but I don't know.
Is it fixable or do I need a new one?

That is the PMS model I use: https://www.aliexpress.com/item/32948772265.html?spm=a2g0s.9042311.0.0.27424c4dupkLtm

Best,

Emetsys
photos of wiring pls
 
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Hi, Thank you for your answers. I use some pth so yes I would need a boost converter if it was a 1s pms. It is however a 2s and I have 2 times to battery in parallels in series.
20191222_075054.jpg
So, without a load I have 8.33v on the output.
With a load it drops to 4.2v.

Best,
Emetsys
 

Stitches

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Hi, Thank you for your answers. I use some pth so yes I would need a boost converter if it was a 1s pms. It is however a 2s and I have 2 times to battery in parallels in series.
View attachment 9910
So, without a load I have 8.33v on the output.
With a load it drops to 4.2v.

Best,
Emetsys
post photos of ALL wiring pls
 
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It works when plugged in, I guess it was because of the short between the 5v and the gnd.
I can post a picture but it is spaghetti.
20191221_232628.jpg
 

GingerOfOz

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Honestly, you should probably scrap all that wiring and start over. That's too much spaghetti, not managing it is only going to cause more issues down the road

Also those batteries you're using are definitely fake, you should really look into getting some legit cells.
 
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Thank you for the comment,
It's not good looking of course but I know where it goes.
The batteries have good rating, so I'll stay with it.
I guess my bms is dead so I'll order another one and wait 3 month.
Does someone know how I could find one quickly in Swiss?

EDIT: Nevermind I'm to stupid I had a problem with gnd. And I love this machine, It's robust with all my errors. Thank you everyone
 
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Stitches

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Thank you for the comment,
It's not good looking of course but I know where it goes.
The batteries have good rating, so I'll stay with it.
I guess my bms is dead so I'll order another one and wait 3 month.
Does someone know how I could find one quickly in Swiss?

EDIT: Nevermind I'm to stupid I had a problem with gnd. And I love this machine, It's robust with all my errors. Thank you everyone
The rating is bullshit, you need legit Panasonics. Those definitely will not run the system for as long as they claim.
 
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These rating were on actual forums not on aliexpress. But if they at least don't explode, I'll ses for myself, if I have to change it, my portable will be easily openable.
 
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