Lipo balance charging

[dolby]

I have just received a battery medic from hobby king but am now confused as to which readings I should trust. My 400w turnigy battery charger shows different readings to the medic which is also different from my true RMS multimeter.
The readings i am getting are:
Charger Medic Multimeter
C1 4.19v 4.14v 4.15v
C2 4.20v 4.18v 4.19v
C3 4.20v 4.14v 4.18v
C4 4.20v 4.16v 4.17v
C5 4.20v 4.17v 4.18v
C6 4.20v 4.15v 4.17v

I would expect that the multimeter would be the most accurate? The Medic and multimeter have a strong correlation except for C3. Should I balance charger with the turnigy charger or the medic? Is the variation between the cell readings from the multimeter enough to justify a balance charge?

 

[SamTexas]

Not great, but again not bad either. Still within the acceptable measurement range. Your worst variation is 0.04V (the middle cell 4.14 to 4.18). That's less than 1%.

 

[Ykick]

I have just received a battery medic from hobby king but am now confused as to which readings I should trust. My 400w turnigy battery charger shows different readings to the medic which is also different from my true RMS multimeter.
The readings i am getting are:
Charger Medic Multimeter
C1 4.19v 4.14v 4.15v
C2 4.20v 4.18v 4.19v
C3 4.20v 4.14v 4.18v
C4 4.20v 4.16v 4.17v
C5 4.20v 4.17v 4.18v
C6 4.20v 4.15v 4.17v

I would expect that the multimeter would be the most accurate? The Medic and multimeter have a strong correlation except for C3. Should I balance charger with the turnigy charger or the medic? Is the variation between the cell readings from the multimeter enough to justify a balance charge?

There's nothing "exact" about cheap & dirty electronics my friend. Good to check with various meters though so you know if something changes but those differences are nothing new or concerning to most of us.

 

[dnmun]

use the dvm readings. what kinda meter?

 

[rocwandrer]

The charger and the medic both use different sensing circuits for each cell. The multimeter reads each cell with the same circuitry. Try testing one cell 6 times with the multimeter if you suspect it. If you get the same reading each time, the multimeter is likely to be consistent across different cells as well. This doesn't mean the multimeter is accurate, necessarily, but it will mean you can trust you don't have an imbalance between cells unless the multimeter reads an imbalance. I have some ebay cell checkers, and when all the cells check out at the same voltage, the cell checks read different for each cell. My charger reads a bit higher than the multimeter, even during balancing in the part of the cycle where it is bleeding charge from the high cell, but it is consistent across cells (so if it says they are balanced they are).