Barrel size matters

Curtech

New Member
Region
USA
Hey all. Looking to replace my factory charger. Picked up the Grin Satiator and their DC 5.5x2.5/2.1mm barrel adapter. Appears to be a good fit, and feels like a good fit, but my battery isn't charging. I'm guessing the barrel on my battery is something else. 5.5x1.5mm? IDK. Not sure how to measure such things. The bike is a Mukkpet Ninja. The factory supplied charger appears to be unbranded but has a model of LBC480305. The battery is from LN Energy Tech Co Ltd and is the model LN-KT-E26. The yellow tip barrel is on the factory charger and the black tip barrel is from Grin (see images).

Anyone with experience on this model battery/charger?
 

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I've got 4 chargers with two different types of barrel plugs, but they all work with all three of my batteries.

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There are adapter kits available that should probably work for you,..


 

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There is no universal standard for the color coding on barrel connectors. Some manufacturers use colors to indicate polarity though. Make sure you are using the correct polarity on the connectors you try.

The Grin Satiator has reverse polarity protection. It won't charge and you get an on screen error message if the polarity isn't correct. Some cheaper chargers do not have this protection and equipment damage could result if the polarity is reversed, so use caution!

You should be able to find an adapter, such as those mentioned by @PCeBiker above, but you may also need a reverse polarity adapter such as this one:

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Welcome to the forum and good luck finding the right connector!
 
Outside of the barrel is the first number... the internal pin is the second number.
Possible you have a 5.5 /1.7 but that's not very common for this application.
Close visual inspection is usually enough to see the difference.
Are you sure the Grin charger is out putting power?
Some batteries require a pulse to start charging... I believe the Grin has this built in or may have a Force Start function to facilitate. Another way to try is to cycle the charger on/off quickly while plugged into the battery.
 
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Yes, the Grin Satiator does have a force start feature. It's activated by connecting the battery and pressing the down arrow on the display.
 
Possible you have a 5.5 /1.7 but that's not very common for this application.
Close visual inspection is usually enough to see the difference.

If I'm staring into my battery charge connector port, I can't see the 0.4mm difference by eye, and I found it impossible to accurately measure the internal pin.
I can't get my caliper into the port to measure the pin.



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I don't know what size my internal pins are, but I have both a tuning fork type and hollow barrel type connector, and they both connect to all my batteries.
 
TY all! Yes the battery does still take a charge. I am able to use my factory charger. I was kinda wiggling the barrel from Grin the other day and for a moment the display shown 'charging' (or similar) so I'm pretty sure the unit works. Also, I have two, and they behave the same, so, hopefully unlikely I got two bad chargers. My battery is center pin positive and the Grin adapter is also center pin positive, so I think my polarity is good. I've attempted to photograph the pin on my battery next to a mm ruler. Given a bit of perspecitve distortion, I'm gonna guess that's a 1.5mm pin (each tic mark is a mm). Unless anyone thinks otherwise, I'll see about finding a barrel adapter that will downsize from center pin 2.5 -> 1.5. That would make it 5.5x1.5mm. Does that sound like a common sizefor the industry?
 

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Yeah.. Not a common size but industry standard isn't much of a concern..
And it is a size....
Screenshot_20250321_071146_Chrome.jpg
It could be camera angle but zooming in on your initial photo.. the yellow tip outside barrel might be slightly larger than the black
Quick search found this:
If that's your charger... maybe if you contact them, they may have a spec on it
 
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I've mesured the OD on the barrel using calipers. The factory barrel and the Grin barrel are identical AFAICT. Using the drill bit size method, the OD is 7/32 which is ~5.5mm, so that checks out. The ID is 5/64 which is nearly 2mm!! o_O That 5/64 dirll bit is just a bit more snug feeling in the Grin adapter than it is on the factory adapter (probably a little looser due to frequent use). Now I'm really stumped!

... and now I feel really stupid :rolleyes: I just hooked up the Grin and held the down button to 'Force charge' and it started straight away, measuring 47.5V. Seems the moral of this story is that the Grin charger is expecting a higher voltage to start off with. 🤦‍♂️ Seems the next step here is to reach out to Grin and ask them just how many V the Satiator is expecting on a 48V nominal battery in order to auto-start charging when plugged in.

TL;DR -- It works! :) TY all!!!
 
I've mesured the OD on the barrel using calipers. The factory barrel and the Grin barrel are identical AFAICT. Using the drill bit size method, the OD is 7/32 which is ~5.5mm, so that checks out. The ID is 5/64 which is nearly 2mm!! o_O That 5/64 dirll bit is just a bit more snug feeling in the Grin adapter than it is on the factory adapter (probably a little looser due to frequent use). Now I'm really stumped!

... and now I feel really stupid :rolleyes: I just hooked up the Grin and held the down button to 'Force charge' and it started straight away, measuring 47.5V. Seems t moral of this story is that the Grin charger is expecting a higher voltage to start off with. 🤦‍♂️ Seems the next step here is to reach out to Grin and ask them just how many V the Satiator is expecting on a 48V nominal battery in order to auto-start charging when plugged in.

TL;DR -- It works! :) TY all!!!
It may be a setting in the Grin setup.
But it can also be the battery BMS waiting for a pulse to accept the charge... This is a safety feature of the battery.
I've had 2 batteries with this.
Measures the voltage of stock charger output with a multimeter being careful not to short circuit. You'll probably see the voltage bouncing continuously.
 
Yes I have the default profile set. It looks like it's the "pulse" thing. I just hooked up the factory charger to a multimeter and I can see the voltage jumping and if you look at the little fan motor in the charge brick, it's constantly jumping-stopping-jumping-stopping, about once a second.
 
I'm running into similar issues. I want to by a satiator but can't find the plug that would fit my battery. Someone mentioned they make one called "other small three pin" but I can't find it on their website. My charger plug looks like an XLR but it is not
 

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If you scroll down on this page, they have a list of adapters. Agree that I do not see one that looks like a perfect match. I'd reach out to their tech support, [email protected], with that pic and see if they can help. They're not too fast, but they are very helpful.
 
If all else fails and you have some basic DIY skills, you can make your own adapter cable. First, cut the OEM charger output cable about a foot from the connector.
That way, you can use either the OEM or Satiator charger.

You can also just simply cut the cord off your charger and splice it onto your Satiator if you only intend to charge with the Satiator.
You can attach a connector to your original charger at a later date.

Keep in mind that the Satiator may not be able to communicate with your battery if there's proprietary software involved, so it would be a good idea to test the Satiator to make sure it will turn on your battery and charge it.


Those proprietary handshakes can be quite complicated and the Satiator may not be programmed to do it properly.

You might have to be playing the right song at the right volume to get the timing right for the secret handshake. 😂

 
Yeah, that's the worry. The handshake isn't the same and even trying a "forced" charge won't work, this after cobbling together the correct connector if I can find one
 
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