accucel 6 problems

Ilyushin76

I am having a few a few problems with the above charger.It charges 1 cell lipos to only 4.15 volts and is not balancing 3 cell batteries correctly.One battery it charged to 4.15,4.20,4.19 v.It shows on the screen when I plug that battery in that all cells are at 4.19 when the are not.I calibrated the charger and it displayed the correctly voltage but reverts back to display the wrong voltage when a battery is plugged in .Anybody have any ideas what is wrong?

Bruthal

Ilyushin76 wrote: »

I am having a few a few problems with the above charger.It charges 1 cell lipos to only 4.15 volts and is not balancing 3 cell batteries correctly.One battery it charged to 4.15,4.20,4.19 v.It shows on the screen when I plug that battery in that all cells are at 4.19 when the are not.I calibrated the charger and it displayed the correctly voltage but reverts back to display the wrong voltage when a battery is plugged in .Anybody have any ideas what is wrong?

What are you using to test the cell voltages?

Ilyushin76

Its a lipo voltage checker I got from ebay but I think its accurate because if I put the 1 cells into a parkzone micro charger it displays the voltage as 4.20 when finished.Are the batteries now damaged with the unbalanced cells ?

Bruthal

Ilyushin76 wrote: »

Its a lipo voltage checker I got from ebay but I think its accurate because if I put the 1 cells into a parkzone micro charger it displays the voltage as 4.20 when finished.Are the batteries now damaged with the unbalanced cells ?

Is it a voltage checker that plugs into the balance lead to check all cells at the same time?

Unbalanced cells themselves do not damage lipos, they are simply like seperate batteries. The problem is when cells are wildly out of balance, a charger that charges the cells through the main lead, and so charging them all in series, can overcharge a cell if the voltage of the others are lower than it.

For example, 4.2v + 4.2v + 4.2v = 12.6v

4.3 + 4.1 + 4.2 also = 12.6 but the 4.3 cell will possibly be damaged. The same happens when discharging in a model, one or 2 cells could go below the minimum if one is higher than others.

But slight imbalances are normal.

Bruthal

I wouldnt go by a voltage checker that checks cell balace by plugging into all cells at the same time via the balance lead.

A multimeter needs to be used on each individual cell. The reason being, that even if the multimeter was slightly off, it will still show if the cells are in balance or not.

Using the voltage checker that checks all cells together would be like using a different multimeter for each cell, and we are measuring to hundreths of a volt here.

I actually use one of them voltage checker things got from HK, as a quick battery checker. It often shows a bit of imbalance in the cells like your saying. But the multimeter says different.

Ilyushin76

Thanks for the replies Robbie.Can a multimeter be connect to the balance lead to read each individual cell ?

Bruthal

Ilyushin76 wrote: »

Thanks for the replies Robbie.Can a multimeter be connect to the balance lead to read each individual cell ?

Yes it can, here is a diagram i did real quick in paint. The 3 cells of a 3s lipo are connected together as in the diagram to make up a battery. The 2 orange connections in the diagram are the connections between the 3 cells to form a battery. They are just conductors to connect the ends of the cells to form a battery from cells in series.

The balance plug wires could differ in colour, but the 2 outside ones will be red and black, and the others might be the same as the diagram, but you can work it out if they are not, by the order they are in. The yellow and blue ones are actually connected to the ends of 2 cells in effect. For a 4 cell lipo there would be 5 balance wires, 3 connected to 2 cell ends and so on for 5 cell and 6 cell lipos etc.



If you look closely, you can see the main power lead is what you connect to the aircraft to power it, and will have 12.6v on a fully charged battery.

You can see the balance plug as well in the diagram, and how each lead from it connects to the cells, to allow chargers to monitor each cells level during charging.

So between red and blue will show the voltage of cell 1, between blue and yellow will show the voltage of cell 2, and yellow and black will show the voltage of cell 3. A fully charged battery should show 4.2v on each cell, but typical readings might be 4.15 or close to that.

The positive polarity each time, will be the wire toward the red one.

The full battery voltage will be shown between the red and black of the balance plug as can be seen in the diagram because they connect to both ends of the battey at the same points as the main leads.

It can be tricky making contact with the balance plug terminals, but it can be done with thin pieces of wire into the balance plug holes, if not with mutimeter probes onto the exposed sides of the terminals on the balance plug. Just take care not to short them if you can avoid it.

I usually pin the balance plug down with 1 probe onto the exposed side of one terminal, then carefully touch the other one beside it to test that cell. Then test the other 2. But i dont do it often, as im well used to the slight inbalances shown on the chargers.

Ilyushin76

Thanks Robbie,measured them with a multimeter and the all seem to be the same voltage so it must be the cheap battery checker at fault.

Bruthal

Ilyushin76 wrote: »

Thanks Robbie,measured them with a multimeter and the all seem to be the same voltage so it must be the cheap battery checker at fault.

Yes i expected that. The accucel 6 itself shows each cell voltage if you have not seen that on it. One of the buttons you press on it cycles between the main charge screen and the cells voltages list while the battery is charging.