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rharris
2007.04.18, 12:40 PM
For anyone out there who knows how to do this, what equipment are you using? How do you get RPM and torque?

Our club would like to invest in some equipment to test motors. We'd like to know if our old motors are bad and if our new motors are good.

Thanks

Sinister_Y
2007.04.18, 04:14 PM
Hi,

I test my motors by running the 'break-in' mode of my LRP pulsar 2 comp charger. The break-in feature allows you to select the output voltage and the charger displays the amp draw by the motor. This works for a general check of performance. A good motor will draw more amps than a bad motor. Note that a bad motor can draw major amperage as well, but you'll hear the difference (if the motor won't spin at high RPM).

Alot of other guys use the drivetrain method, i.e. use the tamiya speed checker. It's like a little dyno for mini-cars...

I used to have some pro 1/10 motor gear (including a dyno), but the freewheel that attaches to the motors a) will not fit a mini-z motor b) software calculations would be incorrect. I always though a mini-z dyno would be cool.

rharris
2007.04.18, 04:51 PM
Thanks,

I've had my eye on the ICE charger for a long time. The motor break in would be cool.

I have a speed checker, but it doesn't seem all that accurate.

With all the guys into slot cars over the years, there has to be something out there.

benmlee
2007.04.18, 05:20 PM
I was just thinking about what to use to test motors yesterday. With that nice heavy PN motor run-in stand, there ought to be a way to test motors with it. Power the motor you want to test. The voltage of the slave motor should be proportional to speed. Hook up a resistor to the slave motor. The current flowing thru the resistor should be proportional to the torque. Unless you calibrate it, you won't be able to get an absolute number, but you should be able to compare from motor to motor. Not sure if that is what you are thinking of, but there seems to be some possibilities there.

bemoore
2007.04.18, 08:22 PM
I used to be heavy into slot cars, and I was surprised that nobody made a dyno for them. Someone did make a "dyno" for Tjets, but it was more of a speed checker and really only measured top speed.

Ninja
2007.04.18, 09:06 PM
I usually just build a motor and try it out. If I like it, I keep it. If I dont like it, I build another.

rharris
2007.04.18, 11:01 PM
I was just thinking about what to use to test motors yesterday. With that nice heavy PN motor run-in stand, there ought to be a way to test motors with it. Power the motor you want to test. The voltage of the slave motor should be proportional to speed. Hook up a resistor to the slave motor. The current flowing thru the resistor should be proportional to the torque. Unless you calibrate it, you won't be able to get an absolute number, but you should be able to compare from motor to motor. Not sure if that is what you are thinking of, but there seems to be some possibilities there.

Cool deal.

I have a PN stand. I may pick up a ICE charger to run the motor, that will tell me exactly what I'm pushing thru the slave motor. It would be very cool to set up some type of guage on (volt meter?) on the motor that I'm testing.

I bet Marvacs (on Harbor in New Port Beach) can help me out with the resistor.

Should be a fun project.

rharris
2007.04.18, 11:03 PM
I usually just build a motor and try it out. If I like it, I keep it. If I dont like it, I build another.

LOL

That is my current method. Only I don't build them, I buy them. When the just don't feel rite anymore, I throw them out.

I'm looking for something a little more exact.

rharris
2007.04.18, 11:13 PM
This is what I want. But I think it would cost a ton to build it.

http://mini-zracer.com/mini-zgallery/data/500/PN_MotorChecker.jpg

Ninja
2007.04.18, 11:32 PM
you can build one with the following parts from tower hobbies
http://www2.************.com/cgi-bin/wti0001p?&I=LXMBS3&P=ML
http://www2.************.com/cgi-bin/WTI0001P?&I=LXNDU3&P=V
http://www2.************.com/cgi-bin/WTI0001P?&I=LXPBP2&P=V
http://www2.************.com/cgi-bin/wti0001p?&I=LXRAW8

total cost is around $130, but for any of you that think it may be worth it, I would love to see someone build one.

You would still require a battery, speed control, and reciever. If someone wants to send me proof that they bought everything on this list, I will donate those :D

rharris
2007.04.19, 12:31 AM
Cool

I Think I'm onto it...

I need,

1. Eagle Tree Systems MicroPower E-Logger V2
2. Eagle Tree Systems Power Panel LCD Display
3. Eagle Tree Systems Optical RPM Sensor
4. ICE Charger

I can use the LCD to get the RPM

http://mini-zracer.com/mini-zgallery/data/500/EagleTree_powerpanel.jpg

Then I think I can just use the ICE to provide 4.5 volts to the (Source) side of the E-Logger V2

http://mini-zracer.com/mini-zgallery/data/500/EagleTreeMicropower.jpg

Then connect the motor to the (Load) side.

Then build a small wheel that can be driven off of the pinion gear. Paint half of the wheel black and the other half white. Then all I need to do is mount the Optical sensor to point 4mm away from the painted wheel.

I think I can actualy pull this off.

Thanks.

LBRC
2007.04.19, 02:44 AM
This is what I use, but the one I like better was made by Yokomo which featured an external optical/rpm sensor allowing you to build a number of different types of stands for no-load and loaded tests.
http://lbspd.com/v-web/gallery/albums/album149/Stock_Micro_T_Motor.jpg

Ninja
2007.04.19, 06:47 AM
@rharris, you got the right idea. ;)

arch2b
2007.04.19, 07:53 AM
that is an interestedin peice of equipment.
http://www.teamorion.com/Products/Motor+Accessories/MPM

Team Orion's Motor Performance Monitor 2 w/CTX (in short called MPM), is designed to help keep your high performance racing motors at top-level performance. The new MPM2 allows you to check your motorís RPM and current draw to evaluate performance and is built with the highest quality components, as found in all Team Orion products. The MPM2 also operates as a top of the line motor break in device and is the perfect power source for your commutator lathe.

The MPM 2 features the CTX mode, which allows for variable break in voltages and current draw readings during each motor test run.


Features:

∑ .01-7.99 output voltage
∑ 13 maximum continuous amps
∑ Dual internal cooling fans
∑ Pulse break-in
∑ 5-step pulse speed w/99 minute motor run delay
∑ 9 sound tones
∑ Blue back lit LCD screen
∑ 3-step motor speed up
∑ High-grade silicone hook-up wires

ORI41614 Motor Performance Monitor 2 w/CTX

rharris
2007.04.19, 10:05 AM
but the one I like better was made by Yokomo which featured an external optical/rpm sensor allowing you to build a number of different types of stands for no-load and loaded tests.

You mean this?

http://mini-zracer.com/mini-zgallery/data/500/Yokomo_MMS.jpg


Part# YZ-MMS
Yokomo Motor Maintenance System

1) Adjustable output voltage.
2) Capable of up to 10A draw.
3) Handles motor up to 7-turn wind.
4) Easy to read backlit LCD display.
5) Displays amp draw, rpm, and condition.
6) rpm sensor included.
7) Lightweight, compact design.

Retail Price: $230.00

Someone told me the RPM would not be correct becouse of the scale. Is this true?

Also, the Optical sensor from Eagle Tree is only good for 40,000 rpm but the magnetic sensor is good for 50,000 rpm. I notice you're Orion is at 47,000. Is there a direct plug in for 130 class motors for the Orion? Or did you have to build something?

briankstan
2007.04.19, 10:32 AM
You mean this?

http://mini-zracer.com/mini-zgallery/data/500/Yokomo_MMS.jpg


Part# YZ-MMS
Yokomo Motor Maintenance System

Retail Price: $230.00




I found a place that has it for $180 with a 10% web discount. so it's a $170.90 shipped.

Also, Kenon has it for $180

HaCo
2007.04.19, 11:59 AM
Well, I have build a motorstand by myself.

Just a microprocessor with a hall sensor and a flywheel with litle magnets on. There are still some issues which make it not very precise. For example I have to use 4 batteries to power the motor (sperated from the microcontroller) because else I have glitches. So, it depends a bit on the batteries state.

Here are some results:
http://img345.imageshack.us/my.php?image=awdmotorua0.png
http://img345.imageshack.us/my.php?image=racermotorgj9.png

Here the tester: http://picasaweb.google.nl/MiniZNieuws/MotorTests

LBRC
2007.04.19, 12:32 PM
You mean this?...

Someone told me the RPM would not be correct becouse of the scale. Is this true?

Also, the Optical sensor from Eagle Tree is only good for 40,000 rpm but the magnetic sensor is good for 50,000 rpm. I notice you're Orion is at 47,000. Is there a direct plug in for 130 class motors for the Orion? Or did you have to build something?

Yes that's the Yokomo I was looking at, not as many features as the Orion but the remotoe sensor has interesting possibilities. Although Iíve been thinking about adding my own external sensor to the Orion with a switch that would let me choose between external and internal. The pulse break in mode of the Orion is a great feature.

On revolution ("r" in rpm) of the sensor is the same no matter how large or small the motor that it turning it.

Not sure what the Orion's actual rpm limit is but Iíve had motors running over 69,000 rpm and suspect that the sensor would fly off before any limit is reached.

The only problem I've had is that some of the smaller motorís, like the Epoch motors, donít draw enough current so you get an error message but even then all you have to do is hook up a Mini-Z motor and let it hang while reading the rpm form the smaller motor and use a multimeter for current and voltage. But as you can see in the photo it works great with even something as small as the Micro-T motors.

I did make and/or modify the sensors to fit different shaft sizes the ones that came with it are for larger motors but thatís an easy fix. For 130 and 180 size motor cans I simply use an old Xmod motor mount temporarily held on the MPM with a drop of RTV and a small piece of silicone wire insulation inserted into the Orion sensor to adapt it to the smaller 2mm shafts. For something even smaller like the Micro-T motors I made new sensors and adapted another Xmods motor mount filling in the inside so that it holds the smaller motor can securely.

HaCo
2007.04.19, 12:41 PM
Aparantly they use the same thing as I do:
http://www.eagletreesystems.com/Boat/images/rpm.jpg

I iventented mine by myself!!! :)

LBRC
2007.04.19, 01:05 PM
Optical sensor, uses a small piece of plastic or even wood dowel painted black with a piece of aluminum tape on each side and a center hole slightly smaller than the diameter of the desired motor shaft, simply press it on insert the motor and test, simple, easy, and very accurate.

HaCo
2007.04.19, 02:24 PM
Well, I use a part in metal, to create a flywheel, so the motor really has to apply force... :)

LBRC
2007.04.19, 03:15 PM
Thatís why I want to modify the MPM with an external sensor option.

But holly cow I forgot about the laser tachometer option! When looking for an RPM meter do a search for ďlaser tachometerĒ they use to be expensive but I noticed that there are some hand held 99,999 rpm inexpensive Chinese versions that are showing up on eBay. Problem is that I donít know how well the cheap knock-offs would work but I think I will order one and see. Would be simple you could even do tire rotation simply put a piece of reflective tape on the tire and point the meter at it.

rharris
2007.04.19, 03:55 PM
Wow, that's a cool option. You can find the hand helds for $25 on ebay. Also a few come with external sensors that can be mounted. One is from the American Tool Company.

That looks like the simple way to test RPM. I don't have an ICE yet, but I've been thinking of picking one up for battary testing and charging LIPO. Can't I use the ICE to test AMP draw from the motor?

benmlee
2007.04.20, 02:16 AM
Here is a possible free rpm counter:

http://www.seven-segments.com/index.php?action=pageshow&id=60&idcat=42

I haven't tried it out yet, but is suppose to use the mic on the computer to pick up the sound of the motor, and converts it into rpm.

Ninja
2007.04.20, 07:00 AM
I had to add that one to my favorites. I wonder now if an old USP cable can be used as a motor break-in power supply using USB 2.0 ports? I believe it can. The problem is, is the power coming from the USB 2.0 constant? or does it need some kind of software installed to tell it to turn on? Hmmmmmmmmm. I think we may be onto something here.

Flashsp-2
2007.04.20, 10:52 AM
I use the Much More Motor Master for all my motor work. It does break-in, RPM, amp draw, etc. Also, I have tested it to 105,000 RPM (yes, that is right :D ). All you need to do is use a small piece of styrene tubing to retrofit the sensor to the 130 sized shaft...

pchan0
2007.04.20, 11:12 AM
I use the Much More Motor Master for all my motor work. It does break-in, RPM, amp draw, etc. Also, I have tested it to 105,000 RPM (yes, that is right :D ). All you need to do is use a small piece of styrene tubing to retrofit the sensor to the 130 sized shaft...

How do you keep the motor in place when checking RPM? Got a motor stand?

benmlee
2007.04.20, 04:13 PM
I had to add that one to my favorites. I wonder now if an old USP cable can be used as a motor break-in power supply using USB 2.0 ports? I believe it can. The problem is, is the power coming from the USB 2.0 constant? or does it need some kind of software installed to tell it to turn on? Hmmmmmmmmm. I think we may be onto something here.

An USB can drive a FET chip to drive the motor. I doube USB can supply 5 amps of power. You will probably fry the computer board.
You can probably make a fully automated motor tester that puts out a graph on a computer. Is probably pretty simple for people that knows about software and microcontrollers. That would be a sweet set-up that shouldn't cost that much.

LBRC
2007.04.20, 08:18 PM
Ya, you wouldnít want to power one from the computer, but a tester that plugged into the computer with a USB cable to graph and store voltage, current, and RPM data would be great, but why stop there as long as weíre connecting it to the computer it might as well be software controlled. Shoot and while were at it how about adding an IR temp sensor, and computer controlled variable magnetic load too.

Lets see all that would be needed is someone good at programming microcontrollers (hardware programming), same person or another to design the electronic circuits, a software writer, someone to actually make and assemble the electronics, and the same or another to make the rest of the hardware (i.e. machining, case, mounts, etc.), no problem. Ok, thatís basically an electronic engineer, a programmer, a technician, and a machinist. Woops forgot the most important part someone to finance the project, ouch, but it would be fun to make and have the ultimate micro/mini RC motor tester, if someone wants to write the software and design the circuits, and pay for it, I would love to try to build it :D

Flashsp-2
2007.04.20, 09:23 PM
How do you keep the motor in place when checking RPM? Got a motor stand?

Yeah, I have a motor stand. It's called my fingers :D That is all I use, maybe not the best option, but it works just fine for me...

ph2t
2007.04.20, 10:41 PM
I tried looking everywhere but no one stocks your fingers flash.... Know where I could buy a set? lol.......

mk2kompressor
2007.04.21, 07:09 AM
i use one of these from much more,i think its the same as the orion one a few pages back
http://i119.photobucket.com/albums/o130/mk2kompressor/motorstuff003.jpg
gpm motor mount added to accept 130 size motors
http://i119.photobucket.com/albums/o130/mk2kompressor/motorstuff002.jpg
http://i119.photobucket.com/albums/o130/mk2kompressor/motorstuff004.jpg
sorry about the crappy pics :o

pchan0
2007.04.21, 08:03 AM
i use one of these from much more,i think its the same as the orion one a few pages back
sorry about the crappy pics :o

You da man! :cool:

rharris
2007.04.21, 10:25 PM
i use one of these from much more,i think its the same as the orion one a few pages back

That's soo cool. Did the 130 mount come with the Much More? or is that custom?

mk2kompressor
2007.04.22, 05:53 AM
its a gpm xmod :o motor mount and two mini servo mounts :D
i had to take the tester to bits and just drill 2 holes for the mount and the sensor for the motor just has a peice of 3mm od styrene tube pushed into it so it fits the smaller 130 arms :)

rharris
2007.04.25, 01:52 AM
Thank you guys for all the information. It's been a big help to me and I hope this will help someone else down the road.

I picked up an Orion from my Local Hobby Shop.

They had the Much More too, but the Orion was $140 and the MuchMore was $200. They are identical in every way except that the much more holds data for 20 motors and the Orion only holds 10.

It was an easy fix to get the sensor pinion to fit. I just stuffed an antenna straw inside it and it fits perfectly now.

For a motor mount I rigged up something using an old mini-z plastic rear mount.

It's very cool to KNOW what your motors are doing.

Thanks again guys...

rharris
2007.04.25, 06:09 PM
Next question.

How do you add load.


It's easy to test RPM and amp draw without load. But how do you accurately add load? I'm thinking some type of pinion on the shaft that lets you add the sensor to the end. Then the pinion drives a wheel that you can apply pressure to. But you'd need to measure the amount of pressure you are adding.

Anyone doing this? Any ideas?

mk2kompressor
2007.04.25, 06:45 PM
ive just started trying hooking up the motor to the tester,but having it installed in a car on a tamiya speed checker,it doesnt give rpm but will give an idea of what your drivetrain and wieght of the car affects the current draw
of the motor
if that makes sense :confused:

arch2b
2007.04.25, 06:48 PM
atomic lists results with a load applied, see the stats for the standard motor for example. maybe someone with connections could ask them how they tested thier motors?

mk2kompressor
2007.04.25, 06:57 PM
id be interested in knowing how they tested them,ive seen torque results from somewhere too :confused:

ill be taking my tester to stafford mini z to test a few of the guys motors,i may make a vid of it in action :D

rharris
2007.04.26, 12:57 AM
Ok, I don't think I really want to build this thing... but it's just so cool.

DIY Motor Test Rig (http://www.aerodesign.de/peter/2001/LRK350/EM-4-2001/LRK_EM_4_2001_eng.htm)

arch2b
2007.04.29, 09:32 AM
has anyone ever seen the kyosho motor testor?
part number: 36213

●コンディションラン、モーターラン、オートーランの3つのモードを装備
●130(ミニッツモーター)/280/380/540クラスに対応した回転センサー付き
●回転数、電圧、電流などのデータは12回分メモリー可能

KYOSHO:K.R.F MOTOR CHECKER Ver.2.0

mk2kompressor
2007.04.29, 12:05 PM
havent seen that one but it looks just like my muchmore one and the orion one a few pages back.
i think the only difference is the memory

rharris
2007.04.29, 11:06 PM
No... didn't know Kyosho made one. Looks like the dyno is in the top. I think I like the side mount better. I'll have to take some pics of the stand I made for mine.

lolo123
2007.09.13, 09:18 PM
its a gpm xmod :o motor mount and two mini servo mounts :D
i had to take the tester to bits and just drill 2 holes for the mount and the sensor for the motor just has a peice of 3mm od styrene tube pushed into it so it fits the smaller 130 arms :)


130 motors = tamiya atomic ones? what kind of servo mount did you use? part no.? thanks!

mk2kompressor
2007.09.14, 01:18 AM
i used cut up xmod front gearboxes for the mount in the end,the servo ones i had were too brittle.

lolo123
2007.09.14, 11:40 AM
sorry do u have pics on em? also e part no. for e xmod gearbox? thanks alot!

benmlee
2007.09.14, 01:49 PM
Ok, I don't think I really want to build this thing... but it's just so cool.

DIY Motor Test Rig (http://www.aerodesign.de/peter/2001/LRK350/EM-4-2001/LRK_EM_4_2001_eng.htm)

Just found this:
http://www.medusaproducts.com/Power-Analyzers/PA-Main.htm

If you are going to build a motor test rig, you can use the power analyzer. It has a scale that can measure the torque of the motor. It all hooks up to a computer to graph the output. Really cool to have. But it will cost you $200, and you have to build a stand to hold the motor and a friction device for the motor.