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amt
07-11-2010, 08:27 PM
I am just getting into electrics and am wondering about the motor numbers. I was wondering about all the numbers the engines are identified by. I purchased 2 motors from RC Timer , a 2212-6, and a 2826-6. I have seen all kinds of numbers on these motors. Along with the front numbers being different, the -6 has all kinds of different numbers. I was told by the manufacturer that the 2 motors I have are almost the same, but the 2826 could handle a little more amps.
Can anyone tell me what all the different numbers mean? Are they the same for all manufactures?
Also, how do you find out what prop and or battery to use with each motor and what thrust you can expect? Is there a formula or chart for these? Where do you buy your batteries and why there?
Sorry for so many questions. I tried to search for these answers but either I am looking in the wrong place or the wrong way or something else.
Thanks in advance for any information you can provide.
Don

Sir Crash-A-Lot
07-11-2010, 08:44 PM
Depends on who made the motors as to what the numbers mean. It is impossible to tell what they mean without the manufacture.

Mike

gramps2161
07-11-2010, 09:22 PM
this is some excellent reading here.

Selecting Electric Power Systems - (http://www.wattflyer.com/forums/showthread.php?t=18521) (http://www.wattflyer.com/forums/images/misc/multipage.gif 1 (http://www.wattflyer.com/forums/showthread.php?t=18521) 2 (http://www.wattflyer.com/forums/showthread.php?t=18521&page=2) 3 (http://www.wattflyer.com/forums/showthread.php?t=18521&page=3) 4 (http://www.wattflyer.com/forums/showthread.php?t=18521&page=4) 5 (http://www.wattflyer.com/forums/showthread.php?t=18521&page=5) 6 (http://www.wattflyer.com/forums/showthread.php?t=18521&page=6) 7 (http://www.wattflyer.com/forums/showthread.php?t=18521&page=7) 8 (http://www.wattflyer.com/forums/showthread.php?t=18521&page=8) ... Last Page (http://www.wattflyer.com/forums/showthread.php?t=18521&page=10))

and here http://www.wattflyer.com/forums/forumdisplay.php?f=17

If you read thru these links you will find out what the numbers mean I have to reread myself seem to have a memory of a sieve when it comes to this electric stuff and the numbers. Sorry I can't answer your question directly but I have learned allot from going over this site looking for the answer. Good luck By the way the motor 2826 is a little bigger in diameter than the other one isn't it.

TylerJCooper
07-11-2010, 09:25 PM
amt,

Welcome to Wattflyer. As I was writing this, Gramps gave you the thread that I was going to also pass on. I read it for the first time 3 years ago and I didn't understand too much, but over the past years, it has been a great learning resource.

Happy Flying,
Coop

amt
07-11-2010, 09:46 PM
Gramps2161:
Thanks for the links. I guess I just have to learn my way around!
I will read the information you mentioned.
Thanks for your quick and informative response.
Don

gramps2161
07-11-2010, 10:51 PM
amt,

Welcome to Wattflyer. As I was writing this, Gramps gave you the thread that I was going to also pass on. I read it for the first time 3 years ago and I didn't understand too much, but over the past years, it has been a great learning resource.

Happy Flying,
Coop


Coop I am still rereading it I am the type that if I don't keep doing something I tend to forget the information.

mesh
07-12-2010, 03:00 AM
The links given are all fine resources, but it should be mentioned that this can be simplified a lot if you just want to know if two motors are nearly the same. Typically you will read about someones set-up on a model, and want to find a motor that performs similarly.

The two really important numbers when you are comparing motors are the weight and the KV.
The weight will tell you what power the motor can handle (watts), and the KV will tell you what size props it will turn.

Yes, of course this is ignoring a lot of parameters, but it is enough to get you 95% of the way there.

If I see an interesting motor I will often go to HobbyKing and look for a motor with the same weight and KV. Most of them have test results done by byers, where they compare the amp draw and thrust with different propellers and voltages.

I also use a free program called Drive Calculator (http://www.drivecalc.de/), using the top menu to specify a weight and KV, to look at similar motors. You can also choose different propellers and voltages to see what the resulting thrust, speed and amp draw would be.

amt
07-12-2010, 04:26 AM
Mesh:
Thanks for the links and information. There is a lot to take in!
Thanks and I appreciate all the help.
Don

fmw
07-13-2010, 05:19 PM
The motor manufacturers would do well to come up with some sort of standard nomenclature. Many of the numbers relate to the physical dimensions of the motors which is fairly meaningless. I like what both Hobbico and Horizon do by naming motors after the equivalent fuel engine power. For instance, the E-Flite Power 25 motor will drive a model with about the same power as a .25 nitro engine.

I didn't read the article that was posted but I assume it tells you how to deal with the current and power specs as well as the KV (rotational speed) numbers to choose a motor. Ideally, you would develop a thrust figure, choose a prop that would produce that thrust at a given rpm, choose a motor that will turn the prop as required well under its power rating and drive it with an ESC with enough power rating to prevent overheating. Sounds simple enough, huh?

Dr Kiwi
08-19-2010, 08:43 PM
***

Dr Kiwi
08-19-2010, 08:46 PM
I am just getting into electrics and am wondering about the motor numbers. I was wondering about all the numbers the engines are identified by. I purchased 2 motors from RC Timer , a 2212-6, and a 2826-6. I have seen all kinds of numbers on these motors. Along with the front numbers being different, the -6 has all kinds of different numbers. I was told by the manufacturer that the 2 motors I have are almost the same, but the 2826 could handle a little more amps.
Can anyone tell me what all the different numbers mean? Are they the same for all manufactures?
Also, how do you find out what prop and or battery to use with each motor and what thrust you can expect? Is there a formula or chart for these? Where do you buy your batteries and why there?
Sorry for so many questions. I tried to search for these answers but either I am looking in the wrong place or the wrong way or something else.
Thanks in advance for any information you can provide.
Don

Those two you mention 2212/6 and 2826/6 allude to stator diameter, stator length and number of turns. The 55g 2212/6 is about 2200Kv and good for ~20A-25A, the 175g 2826/6 is about 730Kv and good for 30A-35A.

The problem is that some manufacturers (Dualsky, for example) use external dimensions... so a 2830 Dualsky motor is the equivalent size of a Suppo 2212! .... and a Dualsky 2826 = 2208 in other peoples' language.... and the 175g 2826/6 above would be close to a 3548 in Dualsky terminology.

kyleservicetech
08-20-2010, 02:05 AM
Also, how do you find out what prop and or battery to use with each motor and what thrust you can expect? Is there a formula or chart for these? Where do you buy your batteries and why there?
Sorry for so many questions. I tried to search for these answers but either I am looking in the wrong place or the wrong way or something else.
Thanks in advance for any information you can provide.
Don

The important motor specifications are "KV", "Ohms", "No Load Current", and "motor weight".

It's kind of difficult to make any decisions on a model setup with a given motor without some considerable help. One I've used many times is available from www.motocalc.com (http://www.motocalc.com), where the first 30 days is free, after that its some $39. That program, or a similar type program will quickly pay for itself, in getting a model that will fly well, without burning up anything. This program, along with many other similar programs are generally easy to use, and will give reasonable predictions on how a given motor/esc/battery combination will fly your model airplane.

As for burning up anything, another near requirement is a meter that will measure just how much current, volts and watts your motor is pulling. A good one is the Astroflight whattmeter. Many others are also available.

These motors are rather dumb. Overload a glow engine, and you will know, it won't run right. Overload an electric motor, and it will happily turn over the prop at super power. Until your model starts smoking like a glow powered model with a smoke tank attached.

The use of an ammeter, or wattmeter, or even a clamp on ammeter will quickly pay for it self. I've got a Sears Craftsman Clamp on Ammeter, their part number #82369. Most clamp on ammeters are AC only, useless for our electric stuff. But the 82369 meter (About $60) will measure AC and DC current, with 0-40 and 0-400 Amperes. That 400 ampere range will easily measure the output current of your automobiles alternator, as well as the current pulled by its starter. And, I've checked this clamp on ammeter against my $350 Fluke 87V meter, that clamp on meter is fairly accurate.

This meter also has a tiny thermocouple temperature reading accessory included that allows reading temperature of your motor, ESC or battery by simply placing the thermocouple against what you want to read.

If you get into the higher powered stuff, say over 500 watts or so, these meters are nearly required, since burning up a 500 watt motor, (or its ESC or battery pack for that matter) can get costly.

As for the larger models, take a look:
http://www.wattflyer.com/forums/showthread.php?t=45222

amt
08-20-2010, 02:38 AM
Dr KIWI
Thanks for the information. I purchased and installed a "BC2826-6 Outrunner Brushless Motor Free Mounts"
(http://www.rctimer.com/index.php?app=goods&spec_id=223)from china. The motor seems strong as when I tried to run it up in the house with a prop saver, it threw the prop shortly after hitting full throttle!
I hope to get everything hooked up soon and try it.

Don

(http://www.rctimer.com/index.php?app=goods&spec_id=223)

amt
08-20-2010, 02:41 AM
Dennis:
Thanks for the link. I will have to find time to read all the information that you posted! I did buy a meter. I got one on ebay that has a backlight and reads up to 100 amps. Before the 2826-6 threw the prop it recorded almost 25 amps.
Thanks again for the help.
Don

kyleservicetech
08-20-2010, 03:51 AM
Dennis:
Thanks for the link. I will have to find time to read all the information that you posted! I did buy a meter. I got one on ebay that has a backlight and reads up to 100 amps. Before the 2826-6 threw the prop it recorded almost 25 amps.
Thanks again for the help.
Don

Hey, welcome to the Electric side of this hobby :D

Dr Kiwi
08-20-2010, 11:18 PM
Dr KIWI
Thanks for the information. I purchased and installed a "BC2826-6 Outrunner Brushless Motor Free Mounts"
(http://www.rctimer.com/index.php?app=goods&spec_id=223)from china. The motor seems strong as when I tried to run it up in the house with a prop saver, it threw the prop shortly after hitting full throttle!
I hope to get everything hooked up soon and try it.

Don

(http://www.rctimer.com/index.php?app=goods&spec_id=223)

I would not use a prop saver on any motor running over 100W! Get a good collet adapter.

Sorry----My conversion was not quite correct... that BC2826-6 is presumably the equivalent of a 2212/6.

ministeve2003
09-26-2010, 03:12 AM
sorry, typed in Wrong Thread...

LOL