Turnigy charger

[muckymits]

My Turnigy 8 charger arrived today from China so pluged my lipo pack in (ex Powacycle LPX) the pack says 25.2 V but the charger says 25.9 so a little worried there also when doing a balance charge it looks to be going around the 3.9 V for each cell is this about right? what the longest I can leave it for and how close should they be?

Sorry about all the questions just not 100% sure, need some moral support guys

 

[amigafan2003]

Need more info.

How many cells does the pack have?

Does it have a BMS?

Does it have a balance tap?

 

[muckymits]

7 cells, not sure cant see any BMS without taking the stanley knife to it and yes got the balance tap, cos Ive got that plugged in

 

[Scottyf]

Hello Muckymits,

First off the chargers are a good addition to any house hold. Now given that your signiture says lipo. I will assume that you are trying to charge a 6 series Lipo Brick since the voltage is a nominal 25.2v.

The settings you will need if that if the correct chemisty is Lipo 6s and then you should be able to Charge / Fast Charge / Balance and storage.
A fully charged 6s Lipo brick will actually be 25.2v which is 4.2v per cell.

It is possible that the charger may be slightly out of calibration. Even if the charger is charging over the 25.2v and hitting 25.9v thats still 4.31v per cell on average. This is over charging the cells. This is a bit dangerous if it does this all the time. (From research you can over charge lipo cells to about 4.8v depending on the cell but is very very dangerous).

There is usually a calibration method for the charger that you can complete if its slightly out.
If you google your charger and calibration there should be some guides if its slightly out and how to adjust it.


Just refreshed and noticed your charging a 7 cell lipo brick. Which is unusual anyway. But if the charger can do up to 8 cells in series its best to check you've slected the correct cell count on the charger as 3.9v is only about 75% charged.

 

[Scottyf]

If you can get some pictures up of the battieries you are trying to charge we will be able to best advise.

 

[muckymits]

I thought it was a 7 cell, its gone in the 7 cell slot(8 wires)? And this is why Ive checked with you guys I am terrified of setting the garage ablaze, its got 3 rooms above it. Could be a nasty mess

 

[Scottyf]

If it has 8 wires its actually a 7 cell battery. Its just one wire is the leading positive balance tap.

Its 7 cell battery.

In which case it should be 25.9v nominal, 29.4v fully charged.

 

[muckymits]

Thats what the charger keeps telling me



see the voltage on it?

 

[Scottyf]

You normally select the voltage on the menus on the charger.

 

[muckymits]

Starting to feel a bit more confident as I couldn't get the voltage that it says on the pack. Ive unplugged it for the night will have another bash tomorrow. This battery is 3 years old but never been used or charged so I need to balance it first.

 

[amigafan2003]

Muckymits - you're ok - let me explain.

When you plug a pack into the charger and connect the balance leads, the charger will detect the cell count. In this case it's identified your pack has seven cells (should show 7s on the display) and then it will display the "nominal" voltage of the pack - in this case 25.9v. Nominal volts for a lipo cell is 3.7v so 3.7v*7cells = 25.9v.

Full charge on a lipo cell is 4.2v so the Turnigy will charge the whole pack to 29.4v (4.2x7).

If I were you though I'd charge the pack up then do a full discharge test on it (this could take all day) as most lipo packs that have sat around unused for 3 years are knackered.

Oh, and buy a celllog8 if you're playing with lipo

 

[muckymits]

Thanks for the confidence boost guys, got the pack balanced charged this after. All up to 4.15 volt ish if I get chance will do a discharge tomorrow or give it a blast out (much more fun). I am sure its a more lively bike now, was road testing a customers bike(Powacycle) last Monday night and it felt so flat compared to my Izip