Charging 7S

[PBO]

Pretty simple....how is it done when the pack is split into 3 & 4 sub packs with their own separate 3S & 4S balance tabs?

If you know & you can explain the conversion process into a 6S balance tab, please do in simple idiot speak

If you know who to charge in split pack configuration, again please do in simple idiot speak

Any constructive input will be appreciated

[pinkpanda3310]

What charger(s) are you using? I'm not familiar with being able to charge more cells than a charger can handle so I'm guessing it's 2 separate charge times or 2 chargers running consecutively. Are you after a wiring diagram?

[Lizard]

When you have split the pack in a seperate 3s and 4s pack you just charge each pack in the normal way.
When you have soldered the two packs in series, you need a charger that is capable of charging 7s.

For wiring look here:
http://scriptasylum.com/rc_speed/lipo.html

Scroll down to the last dropdown box and select "Hi Amp 3s +2s generic connector". This will show you how
to wire for 3s and 2s in series, for your case you just need to add one wire more on each side.

[_paralyzed_]

You need to charge them separately as a 3s and a 4s pack. You cannot charge them together in parallel because of the different voltages.

Your only way to charge as one pack is to get a 7s capable charger and charge in series.

Charge them separately.

[PBO]

The pack has a single set of discharge wires & 2 x separate balance tabs, just like this one below

I must be over thinking it or I'm being a bit thick but I don't get it

7S balance tabs aren't available. The charger can cope with up to 8S & there supposed to be a way of splicing all the balance wires into a single 6S balance tab...???

[Arct1k]

7s Hyperion balance taps I believe are available. I have a 1420 which uses them

You need a 7s charger - you can get away with a 6s balance tap on an 8s battery/charger as the battery lead -/+ act as the other terminals. That's a pretty special config though.

[pinkpanda3310]

So your charger has an 8s balance port? You need to do something like this.



The pic is for 2x 3s, yours will be 1x 7s so the main leads will go straight to the charger. The blank pin on an 8s tap will be at the negative end.

Hope that's what your looking for.

[brian015]

A quick search shows HK had a harness (http://www.youtube.com/watch?v=l4t7-Y3u-04) but complaints that it didn't work right. But I don't see it available on the website.

It should have only 8 wires in the final plug - some comments said it shouldn't. Because two wires on your 3s and 4s plugs are attached to the same spot in the battery stack - you don't need both in a 7s config. You could make your own adapter harness or replace the two taps with a single one (carefully) - or charge through the balance taps (is this what they expect people to do?)

[bdebde]

You still haven't said what charger you have... a balance board is the way to go.

Here's one with the proper plug ins (3s & 4S)... don't know if it will work with your charger.... we don't know what you have!

No rewiring of packs with proper balance board!

[PBO]

Charger isa Powerlab 8

[_paralyzed_]

They show the adapter as in stock at hobby king, but there was some weird glitch, whenever I clicked the thumbnail of the item it went to the battery accessory screen rather than the add to cart screen. I found the adapter by googling the battery> going to the battery page> the adapter was in the "related products" section of the battery page. Anyhoo, here's a vid of the adapter. Looks like you need an 8s male plug, not a 6s, and female 4s and 3s plugs. Vid>

[_paralyzed_]

read the comments on the youtube vids and bust out the voltmeter!

Establish ground and probe the pins, then arrange into the new plug in ascending order. It's a pretty simple plug.

You have an 8s capable charger, so a standard 8s plug is the easiest for you to use. (just leave one pin unused)

[_paralyzed_]

I see the problem!

If you look at the still of the video of the adapter, you see the 3s plug only has 3 wires- it should have 4 wires- ground and cells 1,2 and 3.

The 4s plug has 5 wires, and should only have 4 wires- the positive voltages of cells 4,5,6 and 7. Ground is shared and only necessary on the first plug for our new 8s end. The 4s plug should omit the ground wire.

Hobbyking really fudged up that adapter.

[pinkpanda3310]

Originally Posted by _paralyzed_

Hobbyking really fudged up that adapter.

If that wire is not needed for series charging then they haven't really fudged it up then. They've made it so the correct wire gets left out. Each tap can still be used on a stand alone balancer if needed.

What I am worried about is which tap from the battery pack goes first

[_paralyzed_]

Originally Posted by pinkpanda3310

If that wire is not needed for series charging then they haven't really fudged it up then. They've made it so the correct wire gets left out. Each tap can still be used on a stand alone balancer if needed.

What I am worried about is which tap from the battery pack goes first

It's not the correct wire getting left out though, they are tapping into both grounds and thats no good. It should only be one ground going into the charger. My description above explains it.

A simple use of the voltmeter will show polarity and which lead goes where.