motor dyno results

[reaper]

tested motors i have at the moment and will update as i collect more info these are the basic specs any motors sent to me will get a full data sheet with 6 step amp draw etc so if you want to know the exact RPM or amp draw of your motor or just want a new motor running in correctly just send a pm for details (no charge just cover return p&p )

first up
ROCK CRAWLER (mike mizzi)
4cell 130 rpm @ 0.09A
6cell N/A

radline motors
sd
4cell 18090 rpm @ 0.24a
6cell 26370 rpm @ 0.29a
sp
4cell 20640 rpm @ 0.27a
6cell 28230 rpm @ 0.30a
sr
4cell 23410 rpm @0.28a
6cell 36540 rpm @0.41a


RS STAGE 1
4cell 26710 rpm @0.21A
6cell 35190 rpm @0.32A

RS STAGE 2
4cell 33050 rpm @0.47A
6cell 49550 rpm @0.71A

TAMIYA ATOMIC TUNED
4cell 30330 rpm @0.61A
6cell 35850 rpm @0.77A

STAGE 2 ARM IN BB CAN WITH NEO MAGS
4cell 36720 rpm @0.65A
6cell 55230 rpm @0.79A

180 HIGH TORQUE MOTOR (NOT XI)
4cell 16050 rpm @0.31A
6cell 24180 rpm @0.37A

PLASMATOMIC (FERRITE MAGS)
4cell 70290 rpm @2.70A
6cell 87220 rpm @3.41A

540 SIZE 15X2 (just for comparison)
4cell 8100 rpm @5.45A
6cell 11970 rpm @5.60A

MOTORS IM WANTING TO TEST IF ANYONE HAS THEM
rs stage 1 and 2 with neo mags
plasatomic with neo mags
XI 180 motor
and any other hybrid motors
__________________

[BART]

I'm very interested in this, what are you using to put a load on the motors? I have an idea i wanted to use to be able to do a full horsepower graph of a motor at all rpm. Let me know if your interested.

[reaper]

sorry should have mentiond the stats are "free running"
id be very interested in your idea non-the-less

[BART]

I'll write it out later, headed ice skating. My thoughts were that free running does not really tell you anything about a motors performance over a variable RPM range. We dyno locomotives all the time and end up with a horsepower curve over the entire useable rpm range which is where I got the idea.

[reaper]

Originally Posted by ZX9RBART

I'll write it out later, headed ice skating. My thoughts were that free running does not really tell you anything about a motors performance over a variable RPM range. We dyno locomotives all the time and end up with a horsepower curve over the entire useable rpm range which is where I got the idea.

great idea iv been toying with a way of "preloading" they motor but finding an accurate and consistent method has of yet eluded me
as you mentioned the free-running dyno i use is really a tool to tell you if your "tweeks" are working in the right direction

[ppericfe]

very helpful info

[BART]

Originally Posted by reaper

great idea iv been toying with a way of "preloading" they motor but finding an accurate and consistent method has of yet eluded me
as you mentioned the free-running dyno i use is really a tool to tell you if your "tweeks" are working in the right direction

There are a few options to go with and I even have an idea to make a battery dyno that would test cells over a much broader range than usual. For a proper motor dyno you would need a master/slave setup. I dont think it would be too hard to make, basically the motor you are testing would have to have it's pinion mated to a slave motor. The slave motor would now act as a generator and you would hook up varying resistors to the slaves output to shunt it, even better would be a rheostat so that you could have infinitely adjustable output load. You would need two meters, one to measure the voltage put out by the slave and one to measure the current put out by the slave. Voltage times amperage divided by 700 would give you actual horsepower at that given rpm (an adjustable voltage supply to the master motor would help to simulate the ESC). The only other important step would be to baseline the motor which you have already done and to measure it while hooked to the slave with no load attached, this would tell you the amount of dray the bearings and magnets in the slave are consuming and that info would have to be added to your final output readings (basically calculated parasitic draw from the slave). Multiple tests at varying RPM's would give you a true "horsepower" curve that would be much more useful than just peak rpm, it would show you all of the sweet spots the motor has whether it be a monster in the midrange and a dog on top or whatever. Thats my quick off of the top of my head explanation, let me know if your interested and we can go as deep into this as you want, this stuff is my life.

[reaper]

mine will be a much shorter reply as you have covered everything so well
isnt it 746 not 700 you divide it by ?
for the slave motor im thinking one of the tamiya mini pro series (they have a shaft at both ends) this would aid the initial set-up as we could run the master via the tamiya slave that would be in my dyno then as you as you said run the master alone to gauge the drag and magnetic lose in the slave
erm rite iv lost my train of thought now
how we doing so far ?

[BART]

715 is the official scientific number but for corrected electrical horsepower 700 is the number to use. I would love to see this built and used and will help in any way possible, I just dont have the time to do it. I think a battery dyno would be incredible as well, you could match a specific type of battery to a motor based on its performance. Gotta run, going out to eat. I'll check back later.

[reaper]

well im more than happy to build it so if you want to go ahead and start on some ideas and do some number crunching email me the progress and i will get started

[BART]

Originally Posted by reaper

well im more than happy to build it so if you want to go ahead and start on some ideas and do some number crunching email me the progress and i will get started

Theres not many numbers to crunch until it is built, you would definitely need a decent power supply for accurate results, ideally with a potentiometer on it's output...I dont think i would trust batteries because to do it right you would have to make multiple pulls on each motor in order to have what you could call valid data. As far as adding resistance to the slave, once again I think a pot is your best bet as it could simulate infinite real life scenarios. It sounds like you already have a means of measuring RPM so thats covered. It sounds like you dont need a schematic of what I have pictured in my head but if so I'll explain where to hook what up to. There is another way to do it using water as the load but that may be too complex for this application. The only real variable in this whole situation will be heat, each pull will have to be controlled somewhat precisely in order for the data to hold true. Just let me know what, if anything, you need from me.

[BART]

I can also elaborate on my battery dyno if your interested.

[reaper]

ok think i may have the answer
winging its way to me is a new dyno that does much the same as my muchmore but does it with a flywheel as opposed to the bushing with pickups
the advantage of this is that the windows program can now calculate torque by using the spin-up and down-spin of the fly wheel as is used in full size dyno's

now how about this battery dyno ?

[BART]

Give me a few days, home life is a disaster right now.

[reaper]

lil bit of info on the new dyno


IntroductionThe Fantom Racing FACTS Machine is a microprocessor (MPU) controlled accelerometer (dyno) designed for use with any PC or lap top computer running any Microsoft operating system, from DOS 3.3 through Windows 2000 Pro. The Fantom Racing Dynamometer is controlled from a DOS or Windows program from the computer. THIS PROGRAM HAS BEEN CONSTANTLY UPDATED SINCE 1990. No other program in the world contains as many 'Racing Answers' as the Fantom Racing Dyno. The NEW Facts Machine software provides unprecedented information, combined with the Facts Machine dyno unit, you have the ONLY motor tuning tool you will ever need to adjust your motor for the track conditions you will be running under.


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Both the DOS and the Windows version of the software make the necessary calculations so you can determine approximate gearing and tire sizes to make the most use of your battery and chassis combination. The dyno includes DOS software with easy command options allowing you to work your way through the system with very little need for a manual. Because of its simple on-line help files that are menu sensitive, you simply scroll up or down through the file at anytime to refresh your memory about options that may help you develop a better understanding of R/C electric motors.


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The FACTS Machine measures Torque, RPM, and Amps, and then uses these inputs to compute power. Plots of thesevariables are available both in relation to each other as well as in relation to time. Portability, IBM compatibility, and ease ofoperation make the FACTS Machine a SUPER tuning tool. Graphs shown on the screen have been formatted to be accurate within the limits of your screen resolution, and show tick marks along the axes for easy readability.


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The latest Windows version of the dyno software; The Facts Machine works with all versions of Windows from 95 on up. It comes on CD and installs easily. The Facts Machine software is being developed to add many suggestions and options to your motor testing needs; including a new 'Rollout Calculator' for use in Road Racing, be it carpet, dirt or whatever. Now you can use the "FACTS Machine" very effectively for types of racing other than Oval. The new program shows you "Watts Per Inch". 'WPI' means how many watts your motor is putting on the ground to travel 1 inch. Using this factor you can tune your 'stuff' to make better lap times by putting down more power or tuning your car so it 'requires' less WPI to make a lap. Battery variances such as Ni-Cd vs. Ni-Mh are also included in the Facts Machine II program.


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Operational TheoryThe "FACTS Machine" senses the speed of a flywheel with a known moment of inertia and also measures the current being consumed by the motor. The speed of the flywheel at specific time intervals is integrated to obtain the acceleration of the flywheel. The torque output of the motor is computed from the flywheel moment of inertia and the flywheel acceleration. At the same time, the power output of the motor is being computed from the torque output and the flywheel speed. All this information is then made available to the user in the form of graphs, charts and data screens. These options are selected by simply moving through the menu choices to provide output to the screen, your printer, or a file for later use.


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General InformationThe FACTS Machine is manufactured by Fantom Racing. The program is a combination of efforts between Fantom Racing, decCo SoftWare and YOU giving it many facets that other programs don't have because of a narrower scope of thinking. Fantom Racing makes NO guarantee that these programs will work with every computer on the market, however they have been tested on every available 286 and faster machine that we were able to get our hands on since 1990. To work properly, your machine must be 100% IBM compatible, and must be capable of handling some sort of graphics. It also must have a minimum of 640k base memory. The Windows version of the software, Facts Machine is the software of the future as computers move away from the DOS operating environment. Facts runs on every Windows operating system from 95 through XP.
rrp 554 usd

[suicide_star]

hehe, we'll start buying our motors in WPI instead of WHP now. your dyno system seems pretty cool and very thorough, got any screenshots?

[BART]

Sounds nice, do you own this? I would love to see pics of it as well as details on how the motor current consumption is measured. I would hope it is by a shunt and not by a clamp on ammeter. How much was it and what are it's limitations as far as max power of a motor it can measure? I have more questions but will wait until you shake it down before asking.

[reaper]

Originally Posted by ZX9RBART

Sounds nice, do you own this? I would love to see pics of it as well as details on how the motor current consumption is measured. I would hope it is by a shunt and not by a clamp on ammeter. How much was it and what are it's limitations as far as max power of a motor it can measure? I have more questions but will wait until you shake it down before asking.

im waiting for it to arrive but yes i do own it will get you guys some pics and screenshots up as soon as it arrives
i dont think we will ever max this out as it is ment for 540 size motors so should handle our 130 and 180 motors without problem
all readings are taken by the unit no external meters the only thing that is needed is a clean power supply and of course a pc
thye RRP on this baby is $554.99 usd lets just say i got it for a fair bit less