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Namuna
02-06-2003, 01:10 AM
I pulled out my digital multimeter (again) for some more indepth testing...This time for specific current draw from different Motors. Here are the results (I'll leave the conclusions for all of you to come up with, but these numbers are 'interesting' indeed)

The voltage output is constant for all motors (basically the same as the rating of the car battery)

The Test Setup:
Taking you 56k'ers into consideration, I put all the pitures into the Gallery (http://tinyrc.com/gallery/motortests) (so check it all out there)
Took out my Digital MultiMeter (http://tinyrc.com/gallery/motortests/aab) , Helping Hands (http://tinyrc.com/gallery/motortests/aad) and used a small length of Wire (http://tinyrc.com/gallery/motortests/aah). The last time I took out my DMM (http://tinyrc.com/forums/showthread.php?s=&threadid=1501&highlight=multimeter) I ran the mA tests with no load whatsoever (no motor), this time we'll find out what the deal is with the motors.

In order to properly test the current drain, the DMM has to be setup as part of the current flow...Which gets TRICKY doing it yourself (thank gawd for the helping hands!).

http://tinyrc.com/gallery/motortests/aaa
I took the black lead (from DMM, with alligator clip attachment) and locked it down on the metal plate that the motor endbell rest on, then using the wire with the ends stripped I attached 1 end to the metal in the chassis that the motor rests on, then the other end wraps around the motor (while being held by the helping hand clip).

http://tinyrc.com/gallery/motortests/aae
With that rigged up, the only thing left to do is touch the red lead (from the DMM) to the metal on the endbell (of the motor) and press the forward/reverse button to start the current flow and read the results.

Cars Tested: (Both fully charged before tested)
Stock Bit Char-G
Stock ZipZaps

Motors Tested:
http://tinyrc.com/lincoln/Images/Misc/MotorTests/Endbells.jpg
1) ZipZaps 1.6 (Performance)
2) ZipZaps 2.35 (NOS)
3) ZipZaps 2.15 (Turbo)
4) Clone 2.8
5) Tomy 1.0
6) Tomy 2.2
7) Tomy 2.6
8) TinyRC R-Spec
9) TinyRC 3.8

Results
http://tinyrc.com/lincoln/Images/Misc/MotorTests/Max-Min-loads.gif
The R-Spec and 3.8 motors both had problems pulling enough juice to run properly in the ZipZaps, the numbers given were when the PCB would intermittently give the needed amount

http://tinyrc.com/lincoln/Images/Misc/MotorTests/Watts-HP.gif
*MicroHP = 1/1,000,000th of a Horsepower

BenCloned
02-06-2003, 10:00 AM
Awesome, Namuna! I've been begging for actual testing. Great news for R-Spec fans.

The one you left out was the 1.6, which is supposed to be high torque.

And the new ones on the Tiny RC site.

hogjowlz
02-06-2003, 10:09 AM
1.6 = weak not worth mentioning.

kwikbb
02-06-2003, 10:19 AM
Originally posted by hogjowlz
1.6 = weak not worth mentioning.
I for one don't feel this way and would love to see the results, I'd be curious to see effects on draw caused by the higher torque... if that is a consideration at all. I was shocked to see that the draw on 2.2 was 50ma higher than the 2.6 :eek:.
Sweet job Namuna! :D

BenCloned
02-06-2003, 10:25 AM
Now if we could only figure out how to build a tiny dyno...

We could get the RWH and RWT numbers!

Namuna
02-06-2003, 11:32 AM
Originally posted by kwikbb
...I was shocked to see that the draw on 2.2 was 50ma higher than the 2.6


Yup, people thought I was crazy before when I'd say my 2.6 motor would run for much longer than my 2.2 motor...Now I have PROOF of why!

Alright, I'm updating (with pictures) my original post. So if it looks different next time you come back to this thread...That's why. :)

BabyKiller
02-06-2003, 12:09 PM
so to use a r-spec to fullest with mods u need a 150mah battery?

spikeymike218
02-06-2003, 12:17 PM
Originally posted by hogjowlz
1.6 = weak not worth mentioning.

...well 1.0 is weak also, but he mentioned it...also 3.0 was not mentioned and that motor is not weak. maybe he didn't mention it because he didn't have a 1.6 or 3.0 on hand. just because a motor isn't mentioned doesn't mean its weak...

Namuna
02-06-2003, 12:27 PM
Originally posted by spikeymike218
Maybe he didn't mention it because he didn't have a 1.6 or 3.0 on hand. just because a motor isn't mentioned doesn't mean its weak...

You are correct, I can ONLY test motors I have...I don't have a 1.6 or 3.0, nor anything else except for what I tested.

funkymonkey
02-06-2003, 12:35 PM
Namuna, i'm assuming these current draw figures are for 'no load'? If that is the case the figures may be misleading - you need to test them with load on. Seeing as you can't test 'em racing round the track I suppose the test figure is 'maximum load' or stall current - ie hold the motor so its stalled and check current draw then.

This would surely be a better indication of motor strength?

Namuna
02-06-2003, 12:59 PM
Your assumption is correct funkymonkey, the motors ran free with no load.

You have a point about testing for 'strength' and i'll adjust my testbed and re-adjust for max load/stall current...I'd imagine the ZZ motors would have a better outlook under such tests.

But, I do believe that the numbers I did find are significant in that they can give, at least, a general 'Efficiency' of the motors.

Spanky
02-06-2003, 02:19 PM
excellent tests.

i would like to see tests between cars such as the shen, bit, prescious, thunderbolt, etc. to see if they all draw electricity the same way, or if somehow their deisgn is preventing higher or lower charges/voltage going to motor.

kwikbb
02-06-2003, 02:38 PM
Namuna;
Great pics man! I have you to owe for my 'continuing education' in the field of electronics :D
Thanks,
B

BenCloned
02-06-2003, 02:53 PM
Originally posted by BabyKiller
so to use a r-spec to fullest with mods u need a 150mah battery?

Not exactly. If you want run-time, the higher mah rating is what you want. If you're looking for performance, NiCAD's pump out more current.

It's the difference between capacity (mah) and current (wattage).

Kinda like the "Cold Cranking Amps" rating on a car battery. It says nothing about how long the battery will last, but it tells a great deal about power output.

Namuna
02-06-2003, 03:36 PM
Originally posted by BenCloned
It's the difference between capacity (mah) and current (wattage).
[/B]

Just a little correction...

Capacity = mAH
Current = Amperage (Or for our uses, milliamps)
Wattage = Voltage X Amperage

A good thing to keep in mind with all this fun stuff is Ohm's Law (V=IxR), and a delightful thing to help keep it simple is the 'magic' triangle for Ohm's Law.
http://tinyrc.com/lincoln/Images/Misc/MotorTests/OhmsLaw.gif

BabyKiller
02-06-2003, 03:46 PM
isnt mAH=millamps?

BenCloned
02-06-2003, 03:52 PM
Thanks for the correction. You know how it is - at work, mind on other things...

BenCloned
02-06-2003, 03:58 PM
Originally posted by BabyKiller
isnt mAH=millamps?

mAH = thousanths of an amp / hour

Correct me again if I'm wrong, Namua. Highschool was a long time ago.

Namuna
02-06-2003, 04:10 PM
No, you're right on that BenCloned. :)

But I think you'll confuse the heck out of BabyKiller with that answer! :eek:

BenCloned
02-06-2003, 04:30 PM
How about -

mAH = thousandths of an amp run through the circuit in an hour.

BabyKiller
02-06-2003, 04:32 PM
ok thanks

Namuna
02-06-2003, 04:44 PM
Update: I've updated the information on the ZipZaps and Clone motors...I had some of them mixed up.

BenCloned
02-06-2003, 05:02 PM
Namuna -

Which ZZ board are you using in your tests? is it the new one with higher output, or the old one?

The new boards are included in the new ZZ's with the raised buttons on the TX. They seem to have about 30% higher output through the motor circuit: 125mA vs. 87mA.

I've heard reports that the new boards will run all the Bit motors.

Namuna
02-06-2003, 05:10 PM
I bought my ZipZaps the day they were released...Which means it's the first PCB version.

Spanky
02-06-2003, 05:45 PM
what clone is that from?? shen?

Namuna
02-06-2003, 11:19 PM
The clone is a 'MegaToys' car...Whether that means it's the same as a Shen? I don't know.

Knights
02-07-2003, 12:01 AM
haha this is crazy...all this mA stuff is excacly what im' learning about in school right now.

BenCloned
02-07-2003, 09:04 AM
I ran the same no-load test last night just to compare, and got:

In a shen clone,
2.2 Tomy : 80 mA
3.8 TiRC : 80 mA
Shen Motor : 87 mA

The Shen motor looks just like the #4 in Namuna's test, but must have a different wind on the armature.

I didn't have time, or enough free hands to do an accurate load and stall test. Hopefully Namuna had time to do that last night.

Namuna
02-07-2003, 09:33 AM
Didn't get the chance to do the stall current tests last night, I'll try to get to it tonight or this weekend.

Namuna
02-08-2003, 06:11 PM
As promised, here are my findings of 'Stall Current'...

Stock Bit Char-G:
1.0 = 86mA
2.2 = 195mA
2.6 = 200mA
R-Spec = 230mA
3.8 = 225mA
ZZ Green (Performance) = 104mA
ZZ Red (Turbo) = 185mA
ZZ Yellow (NOS) = 152mA
Clone Pink = 171mA

Stock ZipZaps
1.0 = 64mA
2.2 = 80mA
2.6 = 98mA
R-Spec = 119mA *(see notes below)
3.8 = 120mA *(see notes below)
ZZ Green (Performance) = 83mA
ZZ Red (Turbo) = 106mA
ZZ Yellow (NOS) = 102mA
Clone Pink = 103mA

Notes: The R-Spec and 3.8 motors had problems on the ZZ (this is a 1st generation ZZ, whether they've fixed the resistance issues in the new revisions I can't verify). For the most part the motors couldn't draw any juice (kept pulling up 0), every so often it would sputter up to the amount given...My theory is that since the max output the ZZ can do is ~115mA (based on my readings on THIS (http://www.tinyrc.com/forums/showthread.php?s=&threadid=1501) thread) it had a serious problem supplying the R-Spec and 3.8 with what it could.

Alright, let's do some number crunching and see what kind of HORSEPOWER these motors put out!

1 horsepower = 746 Watts
Watt = Voltage X Amperage

For the sake of simplicity (and since the real differences are nominal) we'll say the voltage was constant through all tests at 1.3v. Since the ZipZaps board is less than forthcoming with good results, i'm just going to figure things out from the Bit Char-G point of view.

Alright, here's the results (for easier reading, I've multiplied all numbers by 10,000...Since these motors are all in the range of 1/10,000th of a Horsepower...I'll call it MicroHP, since I don't know the term for 1/10,000th)

Tomy 1.0 = 1.50 MicroHP (30mA avg. draw)
Tomy 2.2 = 3.40 MicroHP (80mA avg. draw)
Tomy 2.6 = 3.49 MicroHP (30mA avg. draw) *efficient AND quick!*
TinyRC R-Spec = 4.01 MicroHP (105mA avg. draw)
TinyRC 3.8 = 3.92 MicroHP (80mA avg. draw)
ZipZaps Green (Performance) = 1.81 MicroHP (20mA avg. draw)
ZipZaps Red (Turbo) = 3.22 MicroHP (27mA avg. draw)
ZipZaps Yellow (NOS) = 2.65 MicroHP (33mA avg. draw)
Clone Pink (OEM ZipZaps) = 2.98 MicroHP 25mA avg draw)

I'll pretty this all up on Monday (when I get into work), I don't have access to my graphics programs right now at home.

BenCloned
02-09-2003, 12:59 AM
That is some great info! Now, if we could figure out how to measure the torque...

How about we move the decimal two places to the right on the MicroHP rating. It wouldn't change anything, except to make it sound more to scale.

Eg: MicroB 1.0: 1.50 MicroHP would read 150 MHP!
It just sounds more exciting.

Not that it matters!:rolleyes:

Namuna
02-09-2003, 01:23 PM
Hehe, that's not a bad idea BenCloned, and I believe there's a name for that...Nano (for 1/1,000,000th)

Hmmm, 150 NanoHP, that's got a nice ring to it!

I think I'm going to pickup an AC-to-VDC adapter from RadioShack and do the tests over again, this time with no PCB variations so we can get a more precise look at what the motors can do and what they need to do it.

kwikbb
02-09-2003, 03:28 PM
Originally posted by Namuna
Hehe, that's not a bad idea BenCloned, and I believe there's a name for that...Nano (for 1/1,000,000th)

Hmmm, 150 NanoHP, that's got a nice ring to it!

I think I'm going to pickup an AC-to-VDC adapter from RadioShack and do the tests over again, this time with no PCB variations so we can get a more precise look at what the motors can do and what they need to do it.
I'm gonna start callin' you Dexter lol... ' Uh oh Back to the Lab Again', 'Oh no Back to the Lab again'... the Mad scientist never sleeps! :cool: :)

Namuna
02-10-2003, 11:05 AM
Alright, I pretty up the numbers and put it all on the original post.

Enjoy.

BenCloned
02-10-2003, 06:36 PM
Originally posted by Namuna

1 horsepower = 746 Watts
Watt = Voltage X Amperage

Tomy 1.0 = 1.50 MicroHP (30mA avg. draw)
Tomy 2.2 = 3.40 MicroHP (80mA avg. draw)
Tomy 2.6 = 3.49 MicroHP (30mA avg. draw) *efficient AND quick!*
TinyRC R-Spec = 4.01 MicroHP (105mA avg. draw)
TinyRC 3.8 = 3.92 MicroHP (80mA avg. draw)
ZipZaps Green (Performance) = 1.81 MicroHP (20mA avg. draw)
ZipZaps Red (Turbo) = 3.22 MicroHP (27mA avg. draw)
ZipZaps Yellow (NOS) = 2.65 MicroHP (33mA avg. draw)
Clone Pink (OEM ZipZaps) = 2.98 MicroHP 25mA avg draw)


Namuna- When you posted these #'s in the chart on your original post, you changed the values from this post. What happened?

Also, are you calculating wattage from the no-load figure or the loaded draw?

Namuna
02-10-2003, 11:24 PM
Crap, you're right BenCloned...That's NanoHP for NO LOAD.

Alright, gotta update...Again. :)

Namuna
02-10-2003, 11:57 PM
It's late, I'm going to bed...Here's the updated chart...I'll fix it on the main page tomorrow.

BenCloned
02-11-2003, 09:37 AM
Thanks. For a moment there, I thought my math teacher had failed me.

Usually when a manufacturer lists the specs on an engine, they list peak power as a selling point. How about it, Tiny? Maybe another stat to add to the names of the motors you sell, since there was the whole motor naming contest - we may have something here.

TypeZer0
02-14-2003, 01:33 PM
just to clarify things, micro means onemillionth or 1/1,000,000 and nano means one-billionth or 1/1,000,000,000. i could post up a quick chart of those prefixes if anyone cares

Namuna
02-14-2003, 03:54 PM
Thanks for the correction, I've updated the pic on the original post.

hogjowlz
02-19-2003, 01:58 PM
namuna i think your pink clone motor is different than the one i have because there is now way that the tomy 2.6 gets more horsepower.

Jtskty
02-20-2003, 08:36 PM
More watts = more torque right? I want to know because I'm doing a project and I need a motor with a TON of torque. What would you get for that? I have a zip zap and it's getting a 2 cell mod if that matters.

:blift: :btc: bc24c b49m

now that I look at that chart it looks to me like the rspec has more torque than the every other motor. even the lower rpm ones. is that correct?

Sorry for being such a newbie but I really need to know.:p

BenCloned
02-21-2003, 07:40 AM
Your PCB has as much to do with usable torque as the motor does. Zips put out less current than Bits, and some clones deliver even more. The R-Spec is your best bet if your PCB can handle it. Early Zips can't without PCB mods.

Jtskty
02-21-2003, 07:47 AM
So if the pcb can handle it the rspec has the most torque out of all the motors tested? Even the 1.0?

b10 vs.brspec

BenCloned
02-21-2003, 08:05 AM
A 1.6 is supposed to have lots of torque, but Namuna didn't have one to add to his test. Of the motors tested, the R-Spec seems to draw the most juice, and should therefore have the most torque.

fuzzy2cell
02-21-2003, 04:35 PM
Originally posted by BenCloned
Now if we could only figure out how to build a tiny dyno...

We could get the RWH and RWT numbers!
about that dyno, it's not so hard to do. Got a treadmill? take the speed that the zz or ms or anything ran ( the number the treadmill was at when it wasn't accelerating, and wasn't decelerating, but still moving) and multiply it by 70. that is you Scale mph! mine goes 580 with a 6v battery mod

Spanky
02-21-2003, 05:11 PM
about that dyno, it's not so hard to do. Got a treadmill

thats not true. the dyno would measure torque...hp that kinda stuff, not speed. a spedometer measures speed.

RWT= R ear Wheel foot pounds of Torque
RWH = Rear Wheel Horsepower.

i think you got your terms midxed up..


also, you really need to resize your photo, thats to big.

BenCloned
02-21-2003, 08:58 PM
Spanky's got it! Any ideas, all you bit scientists?

fuzzy2cell
02-22-2003, 11:37 AM
sorry about that speed thing:( i think there might be some mathmatical equasion you could do to find the horsepower, if the mph is given (honors math student) you'd have to take the weight into effect too

BenCloned
02-23-2003, 12:20 AM
Horsepower is calculated from torque and RPM. I don't have the equation handy, but I know where to look it up. Basically, what we need is a practical way to measure actual torque and RPM - at the rear wheels and/or on a stand-alone motor.

Namuna
03-26-2003, 10:44 PM
Coming soon boys and girls...

So far I've been testing for Current draw and usage from these motors.

Next up is ACTUAL RPMs! Once I have the capability, I'll be adding even more indepth specs, as well as tests on MORE motors.

Stay tuned.