I bought the Mini Inferno 09 ARR at a discount from my local hobby shop. Iam getting all of the things that I need and now I am down to just needing a charger for the 6v 500mah receiver battery. Ihappen to have the HP5V2 wall wart for charging the pack for a Walkera helicopter. I hooked it up and it charged the battery. I kept checking for the battery warmth so I did not over charge it. Before you blast me... Yes I know that it has a 12v output and I shouldn't charge a 6v battery with 12v charger but my local hobby shop only has cheap 5.8v chargers and expensive multi chargers. After charging I checked the charge on the pack and it said 6.33 volts.

So my question is there something in line like a resistor so I can use the 12 volt charger to charge my 6 volt battery. Here are the specs for the charger

(on the charger)

Model: HP-5V2
Input: AC 100V- 240V
50Hz - 60Hz o.2 max
Output: DC 12.6 V 1.0 A

I also have a multi charger from radshack that you use on a car battery but it uses temp to figure out full charge. It will do 6, 7.2, and 9.6.

Thank you in advance.

Hi, welcome to rcu. I'm not sure if you even need a resistor. Try clicking the article "All about Wall Wart Chargers" It may help with some info. </p>



http://www.rcbatteryclinic.com/</p>

Great article... Thanks for the info!

Ok so what I have gathered from this is this charger should be able to charge my pack and do it well as it will only draw what is needed to charge my pack as long as I don't go over the calculated time. Also if it is rated at 1 amp then my 500 mah should be at full charge within 1/2 hour? (I will check the amps being delivered the next time Icharge using my volt meter). Am I assuming correctly?

Which brings another question. This pack when used on my 7 cell Walkera pack would trip the LED on the pack from red to green when it was done charging. Will the 5 cell be able to do the same when it is fully charged or will it continue to charge trying to charge it to 8.4v before it will kick it off?

Thanks again for your help

I'm not familiar with the charger or battery (with leds) Here's some observations about a charger that doesn't turn off automatically.

Your battery should run about 8.5-10 volts when full at end of charge) and the 12 volt charger is probably ok to use.
The voltage will be mostly determined by the battery and additionally the charge rate.
The rate will be determined by the charger's output and additionally the battery voltage.

Your calculation of 1/2 hr is very close.

To figure it out in wattage multiply the voltage 12.6 x 1 amp = 12.6 watts
Then to figure the actual current divide 12.6 / battery voltage of 9 = 1.4 amps

The tested or actul current may vary from your calculation and fromn mine as well. According to my calc the time may be closer to 20 minutes. As far as the leds,lights,kicking off I have no idea. Is the charger supposed to stop by itself? The stock 7 cell batt has leds? and stops by itself?

Wouldn't I devide 12.6 by 6 (which is the voltage of the pack) giving me 2.1 Amps?

No the 7cell did not have an LED. The charger itself has an LED that turns green when you first plug it in. When you connect a battery pack it turns red showing that it is charging. Once it was charged the LED turns green and would stop charging. What I was wondering was if the LED would turn green for the 5cell 6v pack when it was fully charged. It didn't when I charged it the first time after 22 minutes and Istopped it because the cells were getting warm and Iwas afraid of over charging the pack.

Yes, if the battery's voltage was 6 volt. A 6 volt (5cell) battery is going to be around 9 volts or so. That is a good way to figure it though.

12/9= 1.33 amps.

 I'm curious to see what you get when measuring it.</p>

In case you missed the edit.

No the 7 cell did not have an <font color="#000000">LED</font>. The wall wart charger itself has an LED that turns green when you first plug it in. When you connect a <font color="#000000">battery pack</font> it turns red showing that it is charging. Once it was charged the LED turns green and would stop charging. What I was wondering was if the LED would turn green for the 5cell 6v pack when it was fully charged. It didn't when I charged it the first time after 22 minutes and  I stopped it because the cells were getting warm and I was afraid of over charging the pack. <span class="info">

I will definately post what my readings are on the next charge. I still have to put the servo's, receiver, throttle and steering linkage in. Then I can do a break in. After that the pack should be pretty drained.

Again thanks for the help.
</span>

I'm not sure what controls the led. It sure seems like it is not reliable for doing the "wrong" battery </p>

It may be voltage,voltage drop, time or something else.</p>

Got the servo's mounted last night and hooked up the steering. SOB this is a ton of fun and I haven't even put any fuel in this thing. What a great kit. Everything fits and more importantly no missing parts (yet ) . I couldn't resist putting in the batteries in the controller and connecting up the receiver. Everything moves. Tonight I am going to hook up the throttle linkage and I am pretty much done. </p>

Anybody out there build RC's from the ground up? Seems like it would be a lot of fun.</p>