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Old 06-30-2005, 11:31 PM   #1
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Default Need Help w/ Li-Po Cells, Discharge Rate? And My BL Motor...

Alright, I got a Hacker Brushless Motor. The information for the motor...

Hacker B20-22s BL Motor

60,000 to 80,000 Max RPM
2-3 Li-Po Cells/1200mah (What does the 'mah' rating mean?)
6-10 Nimh/Nicd Cells/1100mah (What does the 'mah' rating mean?)
Max Amps for 15 Seconds - 12 Amps
Continuous Amps - 8 Amps

Quarks Universal 33 Amp ESC

I will be running this in a 1/18 Scale HPI Micro RS4. I would like to run Li-Po cells, my first choice. But I heard that I need a high Discharge Rate on the Li-Po's?

Can anyone how has lots of experience in this help me out? This is my first Brushless Motor and I know about Li-Po's and how dangerous they are and that maybe I should get a Bunker to charge the batteries.

Thanks.

How if you like here are some pics of my car...

http://img275.exs.cx/img275/4069/micrors40012bb.jpg

http://img275.exs.cx/img275/4656/micrors40020qo.jpg

http://img275.exs.cx/img275/9135/micrors40037zl.jpg

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Old 07-01-2005, 12:47 AM   #2
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Try posting here. http://forums.radiocontrolzone.com/f...play.php?f=335
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Old 07-01-2005, 05:13 AM   #3
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Hello,
OK, here is what everything means...

mah is the capacity of your batteries. The more mah, the more capacity the battery has which equates to longer run times. mah is short for milliampere hour.

What the information is telling you is that your Hacker BL motor can handle a 2 - 3 cell LiPo and they are recommending a 1200mah capacity pack. To be honest, if you are using a 2 - 3 cell LiPo pack, you can go with the largest mah rating (more capacity) that can fit into your car. More mah typically means larger battery.

If you are going to run NiMH, you can run from 6 to 10 cells and they are recommending you use 1100mah cells. GP1100's are great for this type of application.

The motor can draw a max of 12 amps for 15 seconds and 8 amps continuously. Your ESC can handle 33 amps so everything should work fine there.

Any good LiPo cell at 1200mah can handle a 12 amp draw (Apogee, Polyquest, etc.). REMEMBER, when setting up any brushless system, you need to make your LiPo selection is based not only on voltage and capacity, but the amount of amps the pack can provide. If a motor can pull 60 amps and the ESC can handle that but you LiPo pack can only provide 20 amps of power, your LiPo pack may not survive. Be careful with your battery selection.

And no, you don't need to be a bunker to charge LiPo's Just make sure that you have a good charger and charge at a max amp rate of 1/100th of the mah rating. For example, the 1200 mah pack should be charged at a max rate of 1.2 amps or lower.

Hope all that helps.
Matt

2-3 Li-Po Cells/1200mah (What does the 'mah' rating mean?)
6-10 Nimh/Nicd Cells/1100mah (What does the 'mah' rating mean?)
Max Amps for 15 Seconds - 12 Amps
Continuous Amps - 8 Amps

Quarks Universal 33 Amp ESC
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Old 07-01-2005, 11:56 AM   #4
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Alright, you've pretty much answered all my questions. I already knew about Mah rating, the more mah, the more runtime.

One last question. Since my Motor is 12 Amps max, can I get a 15 AMP ESC?
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Old 07-01-2005, 12:15 PM   #5
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Sure a 15 amp ESC will handle your motor fine

Get at least a 12C discharge rate Lipo or even better the new 20C Polyquest they will last longer and give you more punch

PolyQuest is the only company that make 20C packs at the moment I think
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Old 07-01-2005, 12:38 PM   #6
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Awesome thanks. I will look around for some Li-Po's.

I just got my Quarks Universal 33amp ESC and I am not really liking it. I want something smaller. And I am not a fan of a on/off switch.

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Old 07-01-2005, 02:28 PM   #7
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Well the best micro car brushless controller is the Castle Creations Mamba 25 ESC but its for sensored motors so check if your motor is sensor based

It can handle any motor that requires 25amps continuous and 50amps burst, it has loads of programming possibilities and CC is very good at customer service and.....its pretty small
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Old 07-01-2005, 08:50 PM   #8
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Do you think this would be pushing my luck?

http://cgi.ebay.com/ws/eBayISAPI.dll...985081090&rd=1
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Old 07-02-2005, 04:03 AM   #9
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I think you will be a little short on power with that Lipo, its only a 10C continuous discharge rate (9amps) so you might experience cogging and the Lipo will get warm and wont last very long since you will be using it to its limit power output

A 1200mah 10C discharge rate (12amp) would be the min for your application

Hope this helps
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Old 07-02-2005, 09:34 AM   #10
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Alright, How about this?

http://www.horizonhobby.com/Shop/ByC...odID=THP13202S

And does anyone know of anyone that carries a lot of these cells?

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Old 07-02-2005, 09:54 AM   #11
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I have one and a charger for it...
Check this thread....
http://www.rctech.net/forum/showthread.php?t=75202
I beleive it is 2100mah and the charger can charge up to three cells. The pack has never been run and is fitted with deans ultra plugs.
Let me know, we can work a deal out..
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Old 07-02-2005, 09:59 AM   #12
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Quote:
Originally Posted by Tbevofreak
Well the best micro car brushless controller is the Castle Creations Mamba 25 ESC but its for sensored motors so check if your motor is sensor based

It can handle any motor that requires 25amps continuous and 50amps burst, it has loads of programming possibilities and CC is very good at customer service and.....its pretty small
The Mamba is not sensored.
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Old 07-02-2005, 08:49 PM   #13
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Um thanks for posting a thread to some items you are selling. But I would rather buy it from an online shop.

...

I just need someone to help me find some Li-Po's that I can use with my Hacker Motor. Or very popular sites that sell lots of Li-Po's or the ones that I listed like the Hi-Tech A.K.A. Multplex ones...

My Hacker B20-22s needs a Sensorless ESC if anyone wants to know. I posted that I didn't like my Quarks 33 Amp ESC and I think I am going to get this instead and send back my Quarks...

Here is what I am lookin at getting... Of course I will reheatshrink it and make the receiver wire much shorter. But its rated at 15 Amps and doesn't have a wire for a Cap and On/Off Switch. I HATE WIRES PERIOD.

http://www2.towerhobbies.com/cgi-bin...?&I=LXGYD0&P=7
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Old 07-03-2005, 05:00 AM   #14
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What you are looking at is a plane ESC. Much different than a car. With a car ESC, you can typically set throttle and brake curves, enable/disable reverse, etc. Check out the RC-Monster.com. Great site for help with BL motor and ESC questions. Here is a link to a GREAT LiPo battery that will work for you.
Apogee LiPo Battery
Hope that helps,
Matt
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