TP 205V charge question

[steve28]

I have the TP 205V cell balancer and I use it for balancing my 3 S TP 2100 packs that I use on my T_REX , and also my DN 2150's . im using a relativley cheap lipo charger , its the Celectra charger from E-FLIGHT .

When charging I always have the TP 205 V connected to the balance plug on my battery , now near the end of the chargeing process the TP 205 comes to life trickling out power from 1 cell or another indicated by the red led's blinking . The TP 205 then beeps a sequence and the yellow light comes on indicating thats its job is done .

The TP 205 always beeps and shows a solid yellow before my Celectra charger tells me that it is completed ( indicated by beeps and flashes ) . The Celectra charger usually takes 5 - 10 min longer to decide that its finished .

During the time from when the TP205 decides it's done and the time the Celectra charger decides its done the TP205 appears to be no longer trickling out any of the cells , I guess they must all be in perfect balance at this point .

Question is Does the TP 205 beep and then display yellow light to indicate charge completion or just cell balance perfect . Should I stop charging when the TP 205 finishes or when the charger finishes , which would be better, which is right ??

[jrohland]

I have used the 205 with several chargers (including a TP-1010 with the data cable). What you describe has always happened to me as well.

The balancer has a very direct link to each cell. It is easy for it to know when each cell is at full charge voltage. The charger is charging a pack, it does not have the immediate feedback from the cells like the 205 does. Also, the 205 appears to be more conservative then most chargers.

Charge until the charger says it is done

What I do depends on the situation. When charging at the field, I pull the cell as soon as the 205 or 1010 say the pack is charged. At home, I have more time to babysit the charge process. At home, I charge until both the 205 and the 1010 say the pack is fully charged.

As to your other question. The 205 balances as long as it is connected to the pack. If you let it sit after the amber light illuminates, the light will go off when the voltage drops. As your packs get older, you will often see the amber light come on, the red overvolt lights will flash and the amber light will go off. This happens because the 205 has pulled current out of the overvolt cells and the pack is no longer full.

At home I charge the packs until the amber light is on, the red lights are off and, the charger shuts off. This can be a challenge on older packs. Sometimes you have to charge, discharge (about 20MAH) and charge again to get everything in synch.

While I'm at it, occasionally the 205 with flash all lights fast and chirp. As far as I can tell, this happens when one or more cell's voltage is too high or too low. When it happens, just leave the 205 connected and start a low current (.25 amp) charge. Usually, the 205 will settle down within about 10 seconds. When it does stop the fast blink+chirp, you can charge at your normal current (1C or 3C).

jrohland