connolly

I have an 8,800 mA Ni-Cad battery that had 9.6 volts and I was wondering if I could use this with my Slow Stick. It has a stock 300 electric motor. I was also wondering what the max capacity of a 300 electric motor was and what the difference between mA and mAH was.

BuzzBomber

My Feedback: (4)

First, do you mean an 8 cell, 800maH NiCad battery? Do you know what "size" the cells are, ie. AA, 2/3A 1/2SC, etc? If the battery weighs less than about 6 oz., it'll probably fly the slow stick just fine with the stock 300 motor. I'm not sure what you mean by "max. capacity" of the 300 motor, but it can handle about 8 amps of current and 9 to 10 volts without frying. To answer your question, mA is a milliamp, a measure of current, whereas maH is a measure of capacity(current drawn over an hour basically). Look at it this way: Your 8 cell 800maH battery should be able to deliver about 9.6 volts at a rate of 800milliamps for one hour. Make any sense?

DBCherry

My Feedback: (4)

Matt gave you great info., I'll add a little bit to it.

Your 300 motor is probably rated for either 6 volts or 7.2 volts. But we all use higher than rated voltage on our motors to get sufficient power from them. It's not at all unusual to use 9.6 volts on a 6 or 7.2 volt motor, it just shortens the life span of the motor a bit. (They're so cheap no one cares.)
Dennis-

connolly

This is the thing that I can't figure out about the battery. On every one of the cells it says 1.2 volts, 1100 mAh. And I thought that It meant it was 8,800 mAh and 9.6 volts for the whole batter because it said 1.2 volts and 1100 mAh on every cell. The cells of my battery are a little bit shorter than a AA but they are also a little wider. And I was wondering if you can fry the engine by putting a battery on it that had too many mAh.Is that possible?[sm=confused.gif] Thank you for reasponding

Volture

My Feedback: (1)

connolly:

Your 8 cells are in series, so your pack is 8 cells x 1.2 volts = 9.6 volts at 1100 milliamp-hour capacity. Cells in series will deliver only the maH of a single cell. If your cells were wired in parallel, you would have a 1.2 volt 8800 mah pack, which wouldn't be useful for RC flight due to low voltage. You can fry a motor with too much voltage, but not with too much capacity. Of course, if your battery has WAY TOO much capacity, your plane will fly poorly, or even be too heavy to get off the ground...

BuzzBomber

My Feedback: (4)

if it's nimh 1100 maH, it's probably 2/3A cells like these: [link=http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXGBM4&P=7]2/3A electrifly pack[/link]. Here's how it works: when you wire battery cells of the same capacity and voltage in series, the capacity stays the same, and the voltage is multiplied by the number of cells. You have 8 1.2 volt, 1100maH cells wired in series, therefore the voltage is 9.6 volts and the capacity is 1100maH. When cells are wired in parallel, the voltage stays the came, and the capacity is multiplied by the number of cells. If you rewired those same cells in parallel, you would now have a battery of 1.2 volts and 8,800maH. Dig? As for your question about frying the motor by using a battery with too much capacity(maH), don't worry about it--it won't happen. You CAN kill a motor with too much voltage, or by drawing too much current(since the two are related, drawing too much current is often a result of applying too much voltage). It sounds like the battery you have will be perfectly fine in a Slow Stick.

BuzzBomber

My Feedback: (4)

Volture, you type too fast!

Volture

My Feedback: (1)

Matt Smith,

I definitely don't type fast, so it must be that great minds think alike!