P- And B- Cables on BMS is too short! How to extend it?

[zedconnor]

I did search and found nothing so decided to ask myself.


DALY Smart BMS

As you can see the cables that come with it are way too short. I cant seem to make them reach the battery when assembling in my custom box.
And their base terminal is an odd one with two screws.(which I cant find here to buy.)

Can I just extend the cable with another wire and screwing the cable lug rings together?

 

[Culchee]

Your idea of extending by bolting two cables together would definitely work... but would create extra resistance to a degree.. because it won’t be just a plain cable from bms to battery...maybe
@upnorthandpersonal would have a better idea.. it def would get you up and running with the two cable idea...

 

[OffGridForGood]

cut off the crimped ring terminal end,
add more wire length with a standard crimped splice tube, and heat shrink over,
add new ring terminal to the end of the new longer wire.

 

[chrisski]

YouTube Videos have been made of these things have been made dropping them in a battery box and hooking one end to a battery case stud. I would extend it with this Blue Sea 200 amp product with the smaller 200C BMS wire on one stud and the larger 65C wire for the same ampacity on the other stud.




If you do extend it with a but crimp, the wire on the BMS is 200C, so it's skinnier than wire at the same ampacity with a lower temp rating that I normally use. I would not want to extend it with 200C wire thinking I could have a voltage loss and that wire is already rated to get super hot.

When ampacity is a factor, except for the 200C wiring on the BMS, I use 65C wire, so the size of a normal wire for the same ampacity would be a lot thicker, so that would make butt crimping it harder.

 

[upnorthandpersonal]

Something like @chrisski mentioned, or a copper plate with a couple of holes in it.

 

[42OhmsPA]

Could always just re-create the cable if you have the tools...

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[zedconnor]

Something like @chrisski mentioned, or a copper plate with a couple of holes in it.

Thanks all for the answers.
How about a connection like this in the picture?
VS using a copper plate with holes?

I am from SEA country so cannot order from that online store.

 

[42OhmsPA]

Thanks all for the answers.
How about a connection like this in the picture?
VS using a copper plate with holes?

I am from SEA country so cannot order from that online store.

That could work but if you have the means to crimp lugs why not make a new longer cable? You could cut a lug at the start of the radius for the hole and have enough material to drill 2 small holes to attach to the Daly...

 

[zedconnor]

That could work but if you have the means to crimp lugs why not make a new longer cable? You could cut a lug at the start of the radius for the hole and have enough material to drill 2 small holes to attach to the Daly...

That's actually a brilliant idea altho I will have to use a bigger lug (50-8) to have a clear enough space.
The wire I am going to be using is 25mm2 wire.
Comparison between 25mm2 wire and bms's default wire in the photos.

 

[Mattb4]

Does not look like a brilliant design decision from Daly. They should supply the 2 screw crimp-on connector that fits their BMS and let the user provide the connecting wire.

Although not ideal I think I would simply go with a bolt. However I would not use a screw type but a standard Hex bolt with two washers and a lock washer. The flat washers would go outside the two ring terminals front and back. This way you can get a good torque on it.

ETA: To be fair though I do like the 2 screw design connector. Less chance of it loosening like a single. Just need to make it available for the consumer to get easily.

 

[zedconnor]

Does not look like a brilliant design decision from Daly. They should supply the 2 screw crimp-on connector that fits their BMS and let the user provide the connecting wire.

Although not ideal I think I would simply go with a bolt. However I would not use a screw type but a standard Hex bolt with two washers and a lock washer. The flat washers would go outside the two ring terminals front and back. This way you can get a good torque on it.

ETA: To be fair though I do like the 2 screw design connector. Less chance of it loosening like a single. Just need to make it available for the consumer to get easily.

I do have hex bolts and washers. It turns out drilling tiny holes (3mm) into a tiny area of the lug is harder than expected with a battery drill. xD

 

[OffGridForGood]

Does not look like a brilliant design decision from Daly. They should supply the 2 screw crimp-on connector that fits their BMS and let the user provide the connecting wire.

True, ...
or, they could provide a little bit longer cable !!!!!!!!

 

[time2roll]

CABAC and Wattmaster out of AU make no hole lugs.

https://www.cabac.com.au/p/electrical-power-connectivity/lugs-and-links/copper/cal150lpb

https://www.tradezone.com.au/produc...table-for-240mm-cable-with-no-hole-17452.html

 

[zedconnor]

UPDATE : I managed to drill a couple hole and attach my own cable lug to the bms. Tho the lug size is massive. I will have to overcrimp it to fit 25mm2 cable in it. It is a 50-8 cable lug.

CABAC and Wattmaster out of AU make no hole lugs.

https://www.cabac.com.au/p/electrical-power-connectivity/lugs-and-links/copper/cal150lpb

https://www.tradezone.com.au/produc...table-for-240mm-cable-with-no-hole-17452.html

I cannot order from those sites unfortunately. I live in a SEA country.

 

[Pierre]

Does not look like a brilliant design decision from Daly. They should supply the 2 screw crimp-on connector that fits their BMS and let the user provide the connecting wire.

Although not ideal I think I would simply go with a bolt. However I would not use a screw type but a standard Hex bolt with two washers and a lock washer. The flat washers would go outside the two ring terminals front and back. This way you can get a good torque on it.

ETA: To be fair though I do like the 2 screw design connector. Less chance of it loosening like a single. Just need to make it available for the consumer to get easily.

Agree with the ‘bolt together‘ idea. I have used this method quite a few times as the Daly cables are generally very short. By heat shrinking the connection it will both provide insulation and improve stability. Also , you can then ‘bend’ the cable at the joint to suit your application.