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Namuna
10-03-2002, 12:26 AM
First, the reason I pulled out the Multimeter was to find out once and for all if my suspicions had any merit...That the electronics in the ZipZaps sent less juice to the Motor than a Bit.

I found some INTERESTING numbers...

How I tested:
Before testing the cars, I put them on their chargers for one charge cycle (45 seconds). Then using a Digital MultiMeter (DMM)*, I removed the Motor from the chassis and attached the leads from the DMM to the contacts for the Motor.

On the Bit:
With a NiMH battery (1.2v @ 100mAH): Pumps out 1.36v @ 275mA
With the stock NiCad Battery: 1.34v @ 250mA

ZipZaps:
With the stock NiMH battery (1.2v @ 100mAH): pumps out 1.30v @ 77mA & 115mA**

Atomic Zcar:
With a Bit NiCad battery: pumps out 1.33v @ 110mA

Well, looks like my suspicions were right! The ZipZaps (and the Zcar, clone) sends considerably less juice to the Motor vs. a Bit! Definitely something to think about!

Oh, something else worthy of noting (especially for any DIY Chargers out there)...The Bit Charger CRANKS out 1.5volts @ 1.5A (it actually spiked to 2.2A when I first put the leads on, but then quickly dropped to 1.5A where it leveled off) to the car while charging!!!!

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* The DMM has an accuracy rating of +/- 0.3% for the voltage and +/- 0.8% for the current.

** Whether I got a shotty ZipZap or they inherently have faulty electronics...Sometimes I'd get readings in the high 70s, sometimes I'd get readings in the 110-120. With the Bit and Zcar, I got near solid readings, so there's definitely something up with the ZipZap(s).

Shacky
10-03-2002, 01:09 AM
Interesting findings Namuna. Here's a thought, could the ZipZap be sending a pulse modulated signal like a booster? That might explain the varying current readings.

The current is still considerably lower, so the Bit is going to deliver more power (more than twice as much). Nice findings!

retroicon
10-03-2002, 01:12 AM
This might be something for all the electronics experts to consider... I'd think that if the batteries are the same in each, it may be possible to change a capacitor somewhere on the board, or multiple capacitors and increase the power on the ZZ's .... any thoughts electronics gurus?

Icon

payaso
10-03-2002, 01:25 AM
Hey Namuna,

Did you test a booster bit chassis with your little doodad? Or do you not have one to test?

silla

Namuna
10-03-2002, 09:36 AM
Originally posted by payaso
Hey Namuna,

Did you test a booster bit chassis with your little doodad? Or do you not have one to test?

silla

Nope, cars used for test:
- Bit Char-G White Skyline, 27MHz (NiMH batt)
- Bit Char-G Blue Skyling, 35MHz (NiCad batt)
- ZipZap Yellow Mustang, 49MHz (NiMH batt)
- Atomic Zcar Black, 49MHz (NiCad batt)

I don't have any boosted Bits, at least not yet. I hear conflicting things about the Booster kit...Specifically that it ISN'T really a boost! But rather the 'boost' is normal juice with the standard Bits and that 'non-boost' is less juice than a standard Bit.

I wouldn't mind pokin and probing a Booster with the ole 'Meter' to find out. ;)

lowerdfool
10-03-2002, 10:33 AM
I figured the zipzaps have a regulated current of power to the motor. Axon found that the voltage was close enough to the same as a bit, but not the current. I'd imagine his idea for an external relay would probably work. I'd be willing to bet if you were to figure where on the zz's board the resistor is you could probably remove it or add a few more in parallel to drop some of that resistance on the current which would make the car speed up.

ax0n
10-03-2002, 11:50 AM
Kick butt. I didn't think to try measuring current. My ZZ puts out 106 mA to teh motor after a full charge (I'm using 1.25 Volt NiMH AAA batteries in my controller, I don't have any "normal" AAA's. That's and average of 5 different tests that ended up putting out 104-107 mA.

Doh - Edit time

I forgot to make my point. I may resume the idea of trying to set up a "booster board" that connects the battery to the motor directly. I may have it only run direct in forward, for simplicity's sake.

my DMM only reads up to 200 mA. Would you mind testing the current of the 1.2v NiMH batteries at full charge?

Namuna
10-03-2002, 12:23 PM
...my DMM only reads up to 200 mA. Would you mind testing the current of the 1.2v NiMH batteries at full charge?

tsk tsk tsk, you're ASSUMING I have the AAA NiMHs to put in the ZZ controller...Lucky for you, I DO have the batteries. :)

I'll test tonight...I'm quite anxious to see the results on this, as I'd LOVE to use NiMH in my controllers (instead of wasting money on the Alkalines).

lowerdfool
10-03-2002, 01:44 PM
Originally posted by ax0n
I forgot to make my point. I may resume the idea of trying to set up a "booster board" that connects the battery to the motor directly. I may have it only run direct in forward, for simplicity's sake.

awsome, that's what I wanted to hear. Just make sure you do a small writeup for us (me) to follow. :D Also, I was wondering since they put the boost option on the controller circuit board I wonder if it's on the zips car board and just isn't used, or is bypassed. This is one reason why I've been trying to dig up data differences on standard and booster boards.

ax0n
10-03-2002, 06:23 PM
Originally posted by lowerdfool
Also, I was wondering since they put the boost option on the controller circuit board I wonder if it's on the zips car board and just isn't used, or is bypassed. This is one reason why I've been trying to dig up data differences on standard and booster boards.

Unfortunately for us, the "decoder" chip inside the car isn't in a nice pin package like the encoder chip in the controller. In my car, the decoder chip is buried under a blastic blob and that means there isn't a good way to find the wire that would be responsible for "boost" on the zip zaps. I'm not sure how it works on the Bits, or on the micro RC cars that are more closely related to the Bits than the ZZ's are. At a casual glance, the Zip Zaps are identical to the bits in almost every way. After some observation though, I'm finding that the zaps are less and less related to the Bits.

QFM Racing
10-03-2002, 09:31 PM
Just check the chip, and if its a TX2, then it does, as all TX2's to my understanding have the boost pin, its just the PCB that wont have the printed etching to take advantage of it.

Also, i wasnt sure you what you meant by the decoder chip, cuz I am amazingly ignorant with electronics, but if you mean freq then I am pretty sure its the 4 black square looking pins along the top of the PCB board that determine the 4 frequencies available.

Somebody school me please...

QFM Racing
10-03-2002, 09:36 PM
Forgot to mention that Kyle and I both have a 2.4v Zip and timed a standard BitDra-G 20' run. Both cars were setup the same, (3.8's, 12:1 gearing, bit tires, etc..) but Kyles has a Bit board and mine is stock ZZ. His car did the run TWO WHOLE SECONDS faster than mine!

My run was 4.74 and his was only 2.81!

Now that is more of a real world example of the difference in performance that the "current" flowing to the motor makes! Quite considerable.

blacksabbath070
10-03-2002, 10:04 PM
what if i put a bit battery in my zip zap would that be wise
i ahve an extra battery soo should i try it?

DesertJedi
10-04-2002, 12:28 AM
Anybody tested Clone (Bullet Cars) boards on a ZZ? Sounds like if the board is the issue, buying a few $10 clones and swapping out the boards would be a great investment for those who already own ZZs...just a thought, I am grossly ignorant when it comes to electronic stuff...but sometimes not knowing has its advantages...."Imagination is more important than Knowledge"...A. Einstein...and who am I to argue ;-)

RebellionInc
11-21-2002, 05:22 PM
i was curious, if i dual battery my ZZ eclipse, would that beat a stock tomy bit or a booster bit? i had a spare tomy stock battery from my Supra bit and my ZZ stock batt. could i do a 2cell with that? anywayz i hope someone responds soon b4 i do it... i gotta race my friend b4 he moves away!!!

payaso
11-21-2002, 05:26 PM
You can't mix nimh and nicad batts... Don't do that mod..

use the same batts.


silla

QFM Racing
11-21-2002, 07:45 PM
Best to use the same cells in a dual batt mod. The ZZ uses a 100mah NiMH (i think) and the bit uses a 50mah NIcd.

Yes a dual cell ZZ would beat a stock bit or booster bit.

RebellionInc
11-22-2002, 02:13 PM
i guess i'll wait untill i get my mod from minircmod on ebay i just bought it a few minutes ago... oh by the way i tried the two batteries and they work but only on the charger:D

Namuna
11-25-2002, 02:15 PM
Well, after reading a lovely 700 page book (Basics of Electricity)...It is now clear that my method for testing the current was flawed.

For PROPER testing of current you MUST put the Multimeter IN-SERIES on the circuit to be tested and the load MUST be present as well...I was testing without the load (Motor).

Someone was nice enough to email me a simple, but ingenious way to test for current...Which is to simply use a non-conductive thin piece of plastic (easily attainable by cutting a slim piece of plastic from a 2liter soda bottle)

Once you have the 'shim', place it between the contacts of the motor and the power plate and then attach your Multimeter on either ends and THEN press the forward/reverse button to send power through...At that point you can get the correct reading.

Here's an illustration:

http://tinyrc.com/lincoln/Images/Misc/CurrentTest.gif

FMZPLAYER1
12-14-2002, 02:16 PM
You'd also get different current readings, depending on how much load the motor is under. If the car is off the ground, and the wheels spin free in the air, the mA's will be very low, if you stall the motor (stop the wheels with your fingers), that should give you a good reading of the motor's max current draw.

The steering coils pull a fair amount of current too, (havent actually measured), but if you drive in a circle a lot, the run time gets cut nearly in half. I think the motor probably draws the same, or less current than the steering coils do, (when the car is just "cruising" and not climbing, or just starting)

I'm going to try an indirect measurement of the current, with the car on a slow charge platform, with the battery at minimum charge. The ammeter will be in series with the charger, so there will be a constant current already going to the car.

Running the motor, or the steering will cause the current to increase (this test will only work on a with a battery that is almost out of charge,so it doesn't have the chance to store up much charge and delay the current readings) It will act more like a capacitor when it's in this state.

FMZPLAYER1
12-14-2002, 08:59 PM
Here's what I got: (Z-car with 2.2 motor)

steering coil ~50mA
motor free run~75mA
motor cruising~95mA (approx)
motor stalled~150mA
motor stall+steering~220mA
cruise+steering~145mA

Used a "C" cell in series with an ammeter (DMM 10A range-for low resistance) There was a very low charging current (30mA) from the fresh C cell thru the ammeter, into the car. This current will barely charge the battery, and running the car motor or steering drains this charge in a few seconds. So the readings would be low, then climb up as the remaining charge depleted.

Had to subtract the 30mA from my original readings to get the above results (ie steering coil result was 80ma-30ma =50mA)

mini rc man
01-30-2003, 09:33 PM
Originally posted by Namuna
Well, after reading a lovely 700 page book (Basics of Electricity)...It is now clear that my method for testing the current was flawed.

For PROPER testing of current you MUST put the Multimeter IN-SERIES on the circuit to be tested and the load MUST be present as well...I was testing without the load (Motor).

Someone was nice enough to email me a simple, but ingenious way to test for current...Which is to simply use a non-conductive thin piece of plastic (easily attainable by cutting a slim piece of plastic from a 2liter soda bottle)

Once you have the 'shim', place it between the contacts of the motor and the power plate and then attach your Multimeter on either ends and THEN press the forward/reverse button to send power through...At that point you can get the correct reading.

Here's an illustration:

http://tinyrc.com/lincoln/Images/Misc/CurrentTest.gif


i got same book

andre
11-30-2007, 09:45 AM
Hey guys
I have been reading all the messages for you guys for a couple of days now, and i finally placed an order on line for my micro's found a deal for about a $100.00 i get 24 cars. do you think that is a deal? Im planning on startin track design now. any suggestions?

andre
11-30-2007, 09:46 AM
Hey guys
I have been reading all the messages for you guys for a couple of days now, and i finally placed an order on line for my micro's found a deal for about a $100.00 i get 24 cars. do you think that is a deal? Im planning on startin track design now. any suggestions?
bc36c

minizzs
12-01-2007, 05:51 PM
that is freaking awsome got 9 for 40 and yours is much better offer

minizzs
12-01-2007, 05:56 PM
id make a fuji track with possible mods but make it realy big a 8 wide (a half a meter)