Some questions about battery leads

[ajac63]

Apologies if this has been covered before and if these seem like silly questions... There are four main leads coming out of my battery pack; one red, one black and two yellow, plus two small rectangular connectors each with six small wires. I'm sure the red and black cables are the main + and - that would go to the esc, but what are the two yellow one's for? Same for the small connectors...

 

[biggman100]

Apologies if this has been covered before and if these seem like silly questions... There are four main leads coming out of my battery pack; one red, one black and two yellow, plus two small rectangular connectors each with six small wires. I'm sure the red and black cables are the main + and - that would go to the esc, but what are the two yellow one's for? Same for the small connectors...

What kind of battery, lipo, nimh, or life? 2S, 3S, 4S, 6S? Who makes it?

 

[ajac63]

Yep, should have said - it's an 8S LiPo 5000 MAh pack by Hacker.

 

[olds97_lss]

All I can think is that it's like a couple lowever voltage taps from the 4S and 6S cells from ground. If you have a volt meter, check the voltage between ground and each yellow. With a 4S or 6S tap, you could more easily tie it to a BEC as most of the ones I've seen only go up to 6S to downconvert to a usable 6-8V. Although, not sure why you would need 2... unless one is 6S and the other is 4S with red/back being the full 8S. Would have made more sense if the colored the yellows different from each other though.

 

[ajac63]

Right, so the yellow wires are lower voltage one's for connecting to a BEC? Apologies if that's not what you meant... Seeing as many ESCs and servos come with a BEC, I wouldn't need a separate BEC unit, then I could just not use the yellow wire? Sorry, still confused. And what about the two small rectangular connectors or plugs? Where would they go?

 

[olds97_lss]

If that's what they are, yeah, could be used for a 6S capable BEC.

Most ESC's have a BEC in them, but they are usually low current and typically a fixed voltage @6V. They usually supply 3A-8A, but typically 5A or less. So people still use a separate BEC wired directly to the input power to have more current and be able to increase the voltage to drive high voltage/current servos, fans and other stuff. Most of the BEC's I've seen are 6S max input.

I just put a castle 10A bec in my revo to take the load off my old esc's BEC as it was pretty weak, only 3A I think. When I turned the steering wheel when the tires were on the ground, it would cause the fans to drop rpm because the esc wasn't supplying enough current to handle the stall current of the servo.

As for the 2 leads... you sure they aren't 2 5 wire balance plugs, not 6 wire?

It really seams like they gave you the yellow's to be able to charge the pack as 2 4S packs vs 1 8S pack. A 4S balance plug has 5 wires on it. Why they gave you 2 yellows, and why it isn't labeled, I'm not 100% sure. Once you solder an end onto the black/red main leads, I don't know how you would use the yellow ones in conjunction with that to try and charge it like 2 4S packs. Many chargers require you to use the main leads and balance leads... someone has to know how to deal with that kind of battery.

What are you using it for?

 

[RustyUs]

I bet if you go into some heli forums they'll tell ya about those LiPo slim split packs.

 

[ajac63]

If that's what they are, yeah, could be used for a 6S capable BEC.

Most ESC's have a BEC in them, but they are usually low current and typically a fixed voltage @6V. They usually supply 3A-8A, but typically 5A or less. So people still use a separate BEC wired directly to the input power to have more current and be able to increase the voltage to drive high voltage/current servos, fans and other stuff. Most of the BEC's I've seen are 6S max input.

I just put a castle 10A bec in my revo to take the load off my old esc's BEC as it was pretty weak, only 3A I think. When I turned the steering wheel when the tires were on the ground, it would cause the fans to drop rpm because the esc wasn't supplying enough current to handle the stall current of the servo.

As for the 2 leads... you sure they aren't 2 5 wire balance plugs, not 6 wire?

It really seams like they gave you the yellow's to be able to charge the pack as 2 4S packs vs 1 8S pack. A 4S balance plug has 5 wires on it. Why they gave you 2 yellows, and why it isn't labeled, I'm not 100% sure. Once you solder an end onto the black/red main leads, I don't know how you would use the yellow ones in conjunction with that to try and charge it like 2 4S packs. Many chargers require you to use the main leads and balance leads... someone has to know how to deal with that kind of battery.

What are you using it for?

It's for a FE boat build I've started; the type of motor I want will be rated at 24+v, hence the battery delivering 29.6v. The reason for wanting a long, thin battery configuration is because I want to distribute the weight of all components in a certain way - basically as evenly and as central as possible.

The two small rectangular plug connectors definitely have six wires each, not five, and one of the wires for one of them is black, all others are red.

 

[ajac63]

I bet if you go into some heli forums they'll tell ya about those LiPo slim split packs.

Yea, that's a good idea, except I didn't realise that the battery pack was intended for an aircraft, only found that out after I received it. What I have done is contacted the vendor to get their advice and have also contacted Hacker themselves. Still to get responses from both. But as long as it delivers the right voltage and amps, does it make any difference if it's intended for an aircraft?

 

[ajac63]

Sorry to bump the thread but I'm still a bit unsure here as to what I actually do with the yellow wires, because as olds97_lss points out, once the red and black wires are connected to the esc, where do the yellow one's go?
Neither the retailer or the vendors, Hacker, have responded to my emails yet, which is just typical...

 

[olds97_lss]

Did some digging, but not finding a good explanation or schematic for it, only that it seems to be called a "split lipo with interconnect". So it would seem that the yellow wires can be wired together to give you the 8S output, or you use a yellow and black or yellow and red to have it be 2 4S packs.

Since there isn't anything on the leads telling you what's what, you need to use a volt meter to check the leads and label them yourself.

I found similar packs here:
https://www.thunderpowerrc.com/products/tp5000-7se55?_pos=8&_sid=c38a015a0&_ss=r

However, the fact that yours has 6 pin balance leads is still confusing... since that would suggest it's 2x5S (10S total) pack.

Might help if you post a closer up photo of the wires as well.

You may really have to wait until hacker gets back to you, unless you find someone that has that specific battery. If you had a volt meter, you could at least try to check some things out yourself.

 

[ajac63]

Did some digging, but not finding a good explanation or schematic for it, only that it seems to be called a "split lipo with interconnect". So it would seem that the yellow wires can be wired together to give you the 8S output, or you use a yellow and black or yellow and red to have it be 2 4S packs.

Since there isn't anything on the leads telling you what's what, you need to use a volt meter to check the leads and label them yourself.

I found similar packs here:
https://www.thunderpowerrc.com/products/tp5000-7se55?_pos=8&_sid=c38a015a0&_ss=r

However, the fact that yours has 6 pin balance leads is still confusing... since that would suggest it's 2x5S (10S total) pack.

Might help if you post a closer up photo of the wires as well.

You may really have to wait until hacker gets back to you, unless you find someone that has that specific battery. If you had a volt meter, you could at least try to check some things out yourself.

Many thanks, and the battery pack info you found is really helpful which says that it's a 5000mAh 7-Cell/7S 25.9V Elite 55C LiPo, Split w/Interconnect one which is almost identical to mine in spec (mine's 8 cells at 26.9v...).
In truth I didn't have a volt meter when I started this thread, but have ordered one which is on it's way, should get it any day; then I'll test the wire combinations that you kindly suggest.
About a closer-up photo of the wires, I can't do that for the time being as I've mislaid the USB cable for my camera would you believe (which is very annoying) and I don't have a smartphone, only one of those oldy-worldy push-button style cell phones from 2011-ish.

Anyway, that's basically it, but thanks again for helping.