Which Crimp Connectors For Overkill BMS?

Stepandwolf

Solar Addict
I’m sorry the crimps didn’t work for you. From your pictures you have used the wrong terminal and crimpers for the 26AWG wire.

It is critical to use the correct tool.

I use the Iwiss crimper for good results.
I have this IWISS and it didn't work with the same ring terminals Chris was using...mine was more messed up than his example.


I think part of the problem is the connectors for an M6 stud assume a larger wire, and the connectors made to work with 26 ga expect a small terminal.
 

Stepandwolf

Solar Addict
I had good luck with these from Crimp Supply.

26-24 Ga. Heat-Shrink Ring Terminals, 1/4" Stud​

11A28016

and this crimper via Amazon: Channellock 909 9.5-Inch Wire Crimping Tool
odd that they use one cavity for insulated and one for non-insulated, for all sizes 10-22...with most crimpers that would be 3 cavities.
 

chrisski

Photon Sorcerer
I have this IWISS and it didn't work with the same ring terminals Chris was using...mine was more messed up than his example.

https://www.amazon.com/SN-28B-Crimping-Terminal-Connector-JST-SM
I think part of the problem is the connectors for an M6 stud assume a larger wire, and the connectors made to work with 26 ga expect a small termin
This is kind of embarrassing. I bought a crimp tool that looked exactly the same as the one I used, which claimed it was good for 26 AWG wire, and I started an Amazon return. After I did this, I read closer and saw there was an adjustment for smaller wire, where I would physically loosen a screw and move the jaws to get it tighter. Instead of returning that tool tomorrow, I may try it.

Anyway, this is the tool from Amazonthat claims to do 26 AWG wires:

3A375A32-BEDA-494C-935A-EA880F2F100E.png
 

toms

Solar Addict
I think part of the problem is the connectors for an M6 stud assume a larger wire, and the connectors made to work with 26 ga expect a small terminal.

I use TE (tyco) connectors, and drill out the 5mm hole to 6mm if required. Mostly i just use 4mm bolts through the busbar. I have seen rivets used successfully long term.

I have attached a picture of the terminals i use, i still double the wire with these.

One day i’ll get around to documenting a build - i’m usually too busy to be messing around with phones when i’m putting a system together.
 

Attachments

  • 6F9CE0AB-3875-443B-8338-C8DC4C616D7D.jpeg
    6F9CE0AB-3875-443B-8338-C8DC4C616D7D.jpeg
    179.1 KB · Views: 2

toms

Solar Addict
This thread is actually a great example of needing to use precisely the correct terminal and crimper to suit the wiring.

Without everything being matched it is very easy to make a bad crimp. I’m certain that is why many people prefer solder joints.

I was lucky enough to work for an automotive manufacturer for a long time and got a lot of information and training on how to terminate and connect wiring.
 

time2roll

Photon Sorcerer
I still like my solder seal terminals. Hit it with the heat gun and it solders and heat shrinks all in one motion. Perfect 5 out of 5.
 

Stepandwolf

Solar Addict
I use TE (tyco) connectors, and drill out the 5mm hole to 6mm if required. Mostly i just use 4mm bolts through the busbar. I have seen rivets used successfully long term.

I have attached a picture of the terminals i use, i still double the wire with these.

One day i’ll get around to documenting a build - i’m usually too busy to be messing around with phones when i’m putting a system together.
Those show to be 22-24ga...that is what mine are...I doubled and even quadrupled the wire. I am considering cutting off a piece of thicker wite and put it in with the 26 and crimp all together. Not my idea, have heard of it being done.
 

time2roll

Photon Sorcerer
I drilled and tapped my bus connectors for a 6-32 screw. I wanted nothing extra on the battery terminal.

22-18 x 1/4 also works fine. Once soldered the size is not critical and the heat shrink provides strain relief.

Crimp is fine too if you have the right stuff.... however seems like many are struggling.
 

Stepandwolf

Solar Addict
I drilled and tapped my bus connectors for a 6-32 screw. I wanted nothing extra on the battery terminal.

22-18 x 1/4 also works fine. Once soldered the size is not critical and the heat shrink provides strain relief.

Crimp is fine too if you have the right stuff.... however seems like many are struggling.
I don't have the tap so that is just one more tool for the project I would like to avoid, especially since I already got the longer grub bolts and terminals to do it that way.
 

TAS CPA

Solar Enthusiast
odd that they use one cavity for insulated and one for non-insulated, for all sizes 10-22...with most crimpers that would be 3 cavities.
Saw Will using it in one of his videos where he said he liked it for small wires. I have the regular crimping tool that works much better for everything other than the small BMS wires. At the time, even went back and watched his video to make sure I was using the same cavity as he was. Don't remember the specific video.

The regular crimper bent the heck out of the lug, making it really weak. Didn't have that problem with the littlest cavity on the manual squeezer (a technical term for sure).
 

Zwy

Solar Addict
I still like my solder seal terminals. Hit it with the heat gun and it solders and heat shrinks all in one motion. Perfect 5 out of 5.
The butt connectors work OK if you use a torch, butane or propane and get the connection warm enough. Using a heat gun will lead to a cold solder joint. I know from experience in years past. Any wire over 14 gauge, the solder seal butt connector may fail over time as the wire will not get warm enough even with a torch to provide a properly soldered joint.

As for the ring or end of wire terminals, you can forget any solder seal terminal. These will not properly bond the terminal to the wire. The crimp and solder ones are better but the crimp length is compromised and the solder doesn't do anything just like the solder seal terminals.

In other words, don't waste time using them, you're much better off just using a crimp style heat shrink terminal, both butt and end of wire. Long term, the solder seal can create a problem due to cold solder joints.
 

time2roll

Photon Sorcerer
Solder flows just fine. No cold solder. I have complete confidence there is a permanent and reliable connection that will outlast the battery.

This only for the very small sensing wires that many seem to have trouble crimping. #14+ I would crimp all day long.
 

Stepandwolf

Solar Addict
Saw Will using it in one of his videos where he said he liked it for small wires. I have the regular crimping tool that works much better for everything other than the small BMS wires. At the time, even went back and watched his video to make sure I was using the same cavity as he was. Don't remember the specific video.

The regular crimper bent the heck out of the lug, making it really weak. Didn't have that problem with the littlest cavity on the manual squeezer (a technical term for sure).
The two cavities seem to be labeled for insulators and not insulators. Two options. I already have at least 6 crimpers, three bought special for this project.
 

Stepandwolf

Solar Addict
By the time you're done we'll have to get you one of those shoe holders for your closet to hold them all. :cool:
Actually I have one of those already, so we are good. I am happy to have bought dedicated crimpers for the various connectors, but almost wish I had known about this crimper before buying all the other ones:
 

toms

Solar Addict
I have one of those crimpers, i don’t use it for the smallest crimps. The Iwiss micro is the go.
 

Attachments

  • 050E8F65-6C03-4743-95B0-FB2822135A97.jpeg
    050E8F65-6C03-4743-95B0-FB2822135A97.jpeg
    487.6 KB · Views: 9

Zwy

Solar Addict
Solder flows just fine. No cold solder. I have complete confidence there is a permanent and reliable connection that will outlast the battery.
You might believe it but I've dissected plenty of these over the years on large wires and also saw failures on the end of wire terminals.

This only for the very small sensing wires that many seem to have trouble crimping. #14+ I would crimp all day long.
For a critical connection such as this, I would not use the solder seal connectors.
 
Top