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hkopium
04-18-2005, 05:53 AM
How long does it take to "slow" charge 8 x Intellect 1200mah batt?

It took me half an hour only for either slow or fast charge mode :confused:

Using XSpeed motor and I can only fast running for 1 to 2 minutes and then slowly play for another 4 mintues or so before the car can no longer move. (Total play time = 5 to 6 minutes) :eek:

I tried 2 different pack of batts and same result.

I suspect the Charger is defective...

interference
04-18-2005, 07:10 AM
Hi,

What charger is it?

for slow charge, u can try C10 rate, which is 0.12A for overnight charge.
Fast charge, try not to exceed 1c rate, which is 1.2A. Batts will take about an hour to charge. Higher current is possible, but more heat generated.

If your pack is new, maybe a few cycles are required to get it working well.

lukeita
04-18-2005, 07:22 AM
Hello
Which charger are you using? Does it sense for delta-peak to find the end of charge?
bye

BitHed
04-18-2005, 07:22 AM
...I am charging a GP1100 6pack at 2a and it takes about half an hour and i can get a 20-30 minute run with a 14t pinion...not too bad...

...8pack GP1100 takes close to an hour to charge...its best done slow and overnight, a watched pot never boils if you know what i mean...I try and run the 8cell with a 16t pinion...it lasts about 20 minutes FULL running or until the xspeed starts to melt the gear cover, whichever occurs first...

hkopium
04-18-2005, 07:31 AM
...I am charging a GP1100 6pack at 2a and it takes about half an hour and i can get a 20-30 minute run with a 14t pinion...not too bad...

...8pack GP1100 takes close to an hour to charge...its best done slow and overnight, a watched pot never boils if you know what i mean...I try and run the 8cell with a 16t pinion...it lasts about 20 minutes FULL running or until the xspeed starts to melt the gear cover, whichever occurs first...


I am using cheap TLP 4000C. Therefore, I have no idea about Delta/Peak etc... Just a plain charger.

Any other brand you guys can recommend? i.e. No "Much More" brand please, it is too expensive.

So my H8 with Xspeed with 8 cells 1200mAh only last full speed for 2 minutes is definitely NOT a good sign...

lukeita
04-18-2005, 07:47 AM
Hello!
On your charger can you see the charging current?
You can calculate charging time easily:
if Cb is the battery pack capacity (for example 1100mAh) and Cc the charging current (for example 100mA), the time is

t = Cb / Cc

Add to that value a 15-20% more because the chemistry process doesn't work at 100%... so with slow charge (C/10) you should wait 10-11 hours to get your pack charged...
bye

PS: Good chargers are Duratrax, GreatPlanes (Triton), Robbe...

interference
04-18-2005, 08:10 AM
HKopium,

What ESC are u running? If still stock, it may be the problem.
When the battery is charged, is it warm, hot or cold.

When battery is too weak for car, is motor, battery or esc very hot?

interference
04-18-2005, 08:11 AM
Oh, for chargers, I recommend the Hobbico quick field charger MKII, its 2 chargers in one. can even charge lithium../

hkopium
04-18-2005, 09:39 AM
HKopium,

What ESC are u running? If still stock, it may be the problem.
When the battery is charged, is it warm, hot or cold.

When battery is too weak for car, is motor, battery or esc very hot?


It is the stock ESC. But many people are running 9.6v with stock electronics and report no problem... :(

After running the car, the motor is hot but not that hot.
ESC heatsink is only warm.

After charging, the batt. is slightly warm. So I suspect the charger is defective since its slow and fast charge are both taking the same time (30mins or so)...

Anyways, I am going to change all the stock electronics soon to Futaba and LRP or even Mamba ESC+Motor.

Will change back to stock motor + 6 cell batt. tonight for testing purpose to see if it is the ESC causing the power drain problem.

mOOsE
04-18-2005, 01:41 PM
My MATCHED pack was matched at 4.0 amps so I can charge up to 4 amps without it getting hot.

hkopium
04-18-2005, 02:08 PM
Ok, it seems the stock ESC cannot handle 9.6v well enough. Kyosho really design its products well so that you must buy the 9.6v Adaptor unit which to be released soon. :mad:

I made a few tests:

(1) Running with 7.2V batt. with Xspeed motor and the servo problem (sudden steering to right side when running at max speed) is gone and the H8 can run at fast speed for over 5 minutes and last totally around 30 minutes as when I first bought it.

(2) I ran the the stock motor (No load) directly hooked to th 9.6v, the motor seems to be spinning at constant speed for over 10 minutes. I stopped since the motor is getting really hot. So the batt and charger seems to be working fine.

So I conclude that it was the stock ESC causing the speed problem.

Oh well, I will buy the following items to run under 9.6v:

(1) Futaba 3PM Tx with HRS Rx ;
(2) Futaba 9650 servo;
(3) LRP Quantum Reverse (with brake) ECS. <--- Would it be too big?

What do you guys think?

interference
04-19-2005, 04:06 PM
why not consider the futaba 330 esc. Pretty cheap in HK. it gets the job done

hkopium
04-20-2005, 12:33 AM
why not consider the futaba 330 esc. Pretty cheap in HK. it gets the job done

I have LRP, GM and Futaba in mind but LRP seems to have the best reputation. :)