How long can you make charging lead extensions?

[Attk11]

Hi I'm new to RCing,

I bought an Arrma big rock (already preformed the pre use maintenance) for my kids and I. We also have a Wltoys 124018 and have a 124019 coming. I bought a Hota D6 pro charger with duel outputs thinking that the duel ports would charge the batteries fast enough. I was wrong, the kids love the big rock and they go through the 2 awana 5000 mah packs pretty fast. I ended up buying a parallel charging board to speed up the process, as well as ordering a 3rd awana 5000 mah pack.

I like to use the bbq to charge the batteries in, that way if there is ever a problem the bbq will contain the inferno. I bought extensions cables for the charging and balance cables. I would like to cut the 8" extensions in half and add 16"-24" of wire, this keeps the charger outside the bbq and allows for space in between the batteries inside the bbq.

Now to the question
How long can you extend the leads before the voltage drop affects the charger's readings? Like if I put 100' of wire in between the batteries and the charger I can’t expect the charger to read the cell voltage properly. I would expect the resistance of the 100' of wire to show full cell of 4.20v to read lower like 3.99v (I actually don’t know just making up a number)

 

[jkflow]

Infinite length, you will never impact the voltage measurement. Stay at the recommend gauge for the charging current or one higher. Longest I ever had was 20ft but becomes cumbersome, you will need both the charging leads and balance plugs.
Realistically I wouldn't go more than 10ft but at the right gauge you can go miles.

 

[SrC]

100ft not realistic IMHO.
1 foot-2 foot max.
Nice Charger BTW
I Have 2 of the HobbyMate version of that charger. Running a dual 24v/400wat PSU with them.

 

[Engineer]

You'll be fine. Resistance of copper wire is around 1-2 ohms per 1000 feet for 10-14 gauge wire so it's negligible for the 1 to 2 feet you are using.

"What do you prefer smoking your ribs with? CNHL or SMC?"

 

[SrC]

Infinite length, you will never impact the voltage measurement. Stay at the recommend gauge for the charging current or one higher. Longest I ever had was 20ft but becomes cumbersome, you will need both the charging leads and balance plugs.
Realistically I wouldn't go more than 10ft but at the right gauge you can go miles.

^^^Good point point. It actually comes down to matching the guage of the wire for the appropriate length. Or Resistance across long lengths works against you amp wise.

 

[jkflow]

Yep, Amps will limit the usable length hence go to next higher gauge if needed but at these values I doubt you have issues with what I see in the pic.

 

[Attk11]

100ft not realistic IMHO.
1 foot-2 foot max.
Nice Charger BTW
I Have 2 of the HobbyMate version of that charger. Running a dual 24v/400wat PSU with them.

Can you share a link to your PSU? I heard that the charger will max out at 15A total (both sides) on AC. I was thinking of a second parallel board but the AC amps will limit its full potential.

 

[SrC]

I purchased the PSU's some time ago here at RDQ. Hard to find elsewhere. It is very popular. And sells out quick.
But whatever you get, It needs to be a 24v 400w minimum spec. 600w even better. Not a 12v PSU. You need to check the settings to adjust the InPut Wattage.
Also if a F/W update is available for your charger, advise to update if you are familiar enough doing it. I did both of mine. Mine are HM. HOTA is the same I believe F/W wise. Just an idea. FWIW.
400w/16.70a/24v Plug and Play Power Supply for ISDT Chargers for Sale (racedayquads.com)

 

[olds97_lss]

Or 24v/1500w/62A: http://lipoconnectionsolutions.com/HP-24v-62A-1500w-Power-Supply-4mm-Bullet-Output-HP24621500B.htm

I got the dell ones from that guy, but the fans annoyed me. They were higher output, but with no load, the fans run 100%, which was really irritating to listen to in my office when discharging or as the charger was doing the last little bit. I ended making my own out of a couple HP 75A/1200W PSU's. Plenty of juice to run my 3 chargers off of.

 

[SrC]

^^^ Probably a better idea. A better setup for sure.

BTW if using a Balance board. DO NOT USE cheapos. They will catch fire! All of the cheap ones. Ask me how I know.
Get an ISDT or Bardwell bal. Board. ( Thermal Resetting Fused)
I am partial to J. Bardwell's.

 

[Attk11]

^^^ Probably a better idea. A better setup for sure.

BTW if using a Balance board. DO NOT USE cheapos. They will catch fire! All of the cheap ones. Ask me how I know.
Get an ISDT or Bardwell bal. Board. ( Thermal Resetting Fused)
I am partial to J. Bardwell's.

Oops, I bought this one:
https://www.amazon.ca/gp/product/B07HPZVN8K/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1
It was $7 when I bought it a week ago.
It does say:
"PROTECTION FUNCTION: Comes with short circuit protection function. Support combined use of 3 parallel charging boards (charge for 18 battery packs at the same time)."

That was part of the reason for extensions, to keep them away from eveything.

 

[Attk11]

Is it ok to use regular stranded copper wire? That's what I have at home, it 22 AWG it's just not silicone.

 

[olds97_lss]

22awg likely isn't heavy enough.

12AWG is as low as I'd go for 24" leads. I used 12AWG silicone high quality wire for my charge leads that I made. The ones that came with my chargers used those cage type banana clips and running 15A through them made them hot. So I replaced all my leads with 12AWG wire and higher quality 4mm split bullets. Even then, charging at 15A, the wires do get +5F over ambient and mine are around 18 inches...

These are like what came with my charger leads:
https://www.amazon.com/Hobbypark-Female-Bullet-Connector-Battery/dp/B071WK8TS2

I replaced them with ones like these:
https://www.amazon.com/20Pair-Bullet-Banana-Connector-Battery/dp/B07BFV4HDQ

And used wire similar to this:
https://www.amazon.com/TUOFENG-Gauge-Electrical-Wire-Black/dp/B0758CKLKK

I wish I had more space than I do for this stuff. I sit 5 feet away when charging/discharging packs with a steel bucket near by. I do keep the packs in fire safe bags when not in use.

 

[Attk11]

I purchased the PSU's some time ago here at RDQ. Hard to find elsewhere. It is very popular. And sells out quick.
But whatever you get, It needs to be a 24v 400w minimum spec. 600w even better. Not a 12v PSU. You need to check the settings to adjust the InPut Wattage.
Also if a F/W update is available for your charger, advise to update if you are familiar enough doing it. I did both of mine. Mine are HM. HOTA is the same I believe F/W wise. Just an idea. FWIW.
400w/16.70a/24v Plug and Play Power Supply for ISDT Chargers for Sale (racedayquads.com)

My software version is 1.0.36

22awg likely isn't heavy enough.

12AWG is as low as I'd go for 24" leads. I used 12AWG silicone high quality wire for my charge leads that I made. The ones that came with my chargers used those cage type banana clips and running 15A through them made them hot. So I replaced all my leads with 12AWG wire and higher quality 4mm split bullets. Even then, charging at 15A, the wires do get +5F over ambient and mine are around 18 inches...

These are like what came with my charger leads:
https://www.amazon.com/Hobbypark-Female-Bullet-Connector-Battery/dp/B071WK8TS2

I replaced them with ones like these:
https://www.amazon.com/20Pair-Bullet-Banana-Connector-Battery/dp/B07BFV4HDQ

And used wire similar to this:
https://www.amazon.com/TUOFENG-Gauge-Electrical-Wire-Black/dp/B0758CKLKK

I wish I had more space than I do for this stuff. I sit 5 feet away when charging/discharging packs with a steel bucket near by. I do keep the packs in fire safe bags when not in use.

Sorry not the charging leads, the balance leads I was going to use 22 AWG.

 

[jkflow]

22 AWG on the balance leads should be ok. Just don't get the idea and get 18" extensions and daisy chain them to 10ft length or something like that.
Those connectors add a lot of resistance while the wire is negligible. I wouldn't daisy chanin more than 3-4 connectors in the entire chain (incl. balance boards).

 

[Attk11]

22 AWG on the balance leads should be ok. Just don't get the idea and get 18" extensions and daisy chain them to 10ft length or something like that.
Those connectors add a lot of resistance while the wire is negligible. I wouldn't daisy chanin more than 3-4 connectors in the entire chain (incl. balance boards).

Thanks,
My plan was to take one and cut it in half and add 24" of wire so I don't have to daisy chain the connectors.

 

[slick2500]

Not trying to thread jack or anything at all, but does anyone know of a power supply that has adjustable voltage and has around 1000w? My Hitec X2 400 for some reason has a max voltage of 18v. I tried searching a while back and most of the ones I found were only around 400w.

And while we are also on the subject of para charging should I not be using these? https://hobbyking.com/en_us/jst-xh-parallel-balance-lead-3s-250mm-2xjst-xh-2.html

 

[jkflow]

Yes, that's the way to do it. Again, you could go up to 10ft or more, if you wanted, with that type of approach.
Just make sure that you do not swap any wires That would be spectacular.


@slick2500 Adjustable in what range? I know of some but they are cost prohibitive.
24V fixed is cheap.

 

[slick2500]

Yes, that's the way to do it. Again, you could go up to 10ft or more, if you wanted, with that type of approach.
Just make sure that you do not swap any wires That would be spectacular.


@slick2500 Adjustable in what range? I know of some but they are cost prohibitive.
24V fixed is cheap.

I want to be able to adjust the voltage to 18v.

-edit- God I are smart I never thought of looking for a 18v psu
This should work https://www.amazon.com/Switching-（SMPS）110VAC-DC18V-Monitoring-Industrial-Transformer/dp/B0782KSTWT

 

[jkflow]

Got it, I was thinking in different lines. You can use older regulated HP supplies. Rocksolid even ~20yrs later, not that expensive but not cheap either.
Sounds like you want a fixed 18V supply, below is truly adjustable 0-20V.

https://www.ebay.com/itm/HEWLETT-PA...150425&hash=item46bba9d2f2:g:8nIAAOSwuBdgIHKw