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Old 11-11-2005, 02:28 AM   #736
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Quote:
Originally Posted by PitCrew
I am not 100% sure on this, and I do think the IB cells are amazing, but.....
now hear me out here.

When voltage is applied to a coil, a certain amount of that voltage is dissapated as heat as the voltage must overcome the reverse EMF produced by the mag field of the magnets. Now as you increase the voltage passing through the coils (hereby increasing the electron pressure) the current passes easier (current being amps) Therefore the motor produces more power by having more voltage to overcome the resistance and emf of the magnets, and therefore draws MORE current (amps). Though the rated capacity of the cells are higher than the GP 3700 the fact that they produce more voltage can (maybe) cause the motor to draw more current than it would have at a lower voltage, thereby decreasing the runtime of the pack on the track.....

This is one of the main reasons that 4 cell racing can go for 8 minutes and much longer if they wanted... Less voltage means less current draw, means longer run time.

Albeit, if used correctly, the extra speed can be used wisely running low wind motors and run time can be made.


Go here: http://www.ajdesigner.com/phpohmslaw...ge_current.php

Resistance does not change. Power output is increased at a higher voltage.


In 4.8 volt racing voltage is reduced, amperage is reduced, resistance is constant. Power equalls volts multiplied by amps. Less volts, less amps equals less power.
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Old 11-11-2005, 02:55 AM   #737
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Pitcrew.... good thinking.... this is all truth and reality on the track

Danny, always coming up with interesting news like us having special cells if we win... of course we take the best we have. And of course the other IB users run cells from the shop... lol! Like IB also GP 'tweaks' their cells continuesly and makes them better... you can buy super low IR - high voltage GP37's here in EU, and am sorry you do not have those... want some cases? We have stock of them.

Phil C and Hyper got the message and understood you need also corner speed to be fast. Hara had none in the first final as he went on to hard tyres, just watch Yoshioka catch Masami the first few laps. Laptimes first final: yoshioka 16.9, masami 17.2, hara 17.5... why does no one post the second final??? Or the 3rd? As there all went different. And how can you be taken out if you are so much faster? Masami lost the race due to a driving mistake as he had to catch up.
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Old 11-11-2005, 06:24 AM   #738
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Quote:
Originally Posted by beerbarron
Go here: http://www.ajdesigner.com/phpohmslaw...ge_current.php

Resistance does not change. Power output is increased at a higher voltage.


In 4.8 volt racing voltage is reduced, amperage is reduced, resistance is constant. Power equalls volts multiplied by amps. Less volts, less amps equals less power.

ahh, but that is only true in a static system. Remember resitance goes up as heat is produced. so as the motor get hotter in 6 cell touring cars because of the added weight and drive train, resistance also increases. You are correct at the start of the race, both R in the equation would be equal. but at any point after time zero, resistance will be higher on the 6 cell tc.
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Old 11-11-2005, 07:52 AM   #739
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It's also one of the reasons why you should tune your motors for a lower amp draw as noted earlier in this thread.....
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Old 11-11-2005, 08:00 AM   #740
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Kewl posts! Thanks guys.
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Old 11-11-2005, 10:59 AM   #741
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Quote:
Originally Posted by Oscar Jansen
Pitcrew.... good thinking.... this is all truth and reality on the track

Danny, always coming up with interesting news like us having special cells if we win... of course we take the best we have. And of course the other IB users run cells from the shop... lol! Like IB also GP 'tweaks' their cells continuesly and makes them better... you can buy super low IR - high voltage GP37's here in EU, and am sorry you do not have those... want some cases? We have stock of them.

Phil C and Hyper got the message and understood you need also corner speed to be fast. Hara had none in the first final as he went on to hard tyres, just watch Yoshioka catch Masami the first few laps. Laptimes first final: yoshioka 16.9, masami 17.2, hara 17.5... why does no one post the second final??? Or the 3rd? As there all went different. And how can you be taken out if you are so much faster? Masami lost the race due to a driving mistake as he had to catch up.

Well if GP is tweaking there cells can you please explain why all the latest GP3700 cases here in the US have gone down in voltage ? That could explain why you say you have plenty of good cells.
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Old 11-11-2005, 11:08 AM   #742
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Should we be suprised that GP would show this kind of mismanagement and poor business judgement (holding/manufacturing better cells for one company than others) and questionable ethics? Althought this has nothing to do with ontrack performance, I sure hope IB holds to a much higher business standard than GP did. I guess I should be more specific and say GPNA. I dont know how ethical their offices are in Europe and Asia.

I am sorry-I am sure people are reading this going' "Ray-what the hell are you talking about?? Taken up Crack lately?" But I have my reasons.
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Old 11-11-2005, 02:21 PM   #743
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Hmmmm.....
Just found this:
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Old 11-11-2005, 02:51 PM   #744
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Quote:
Originally Posted by rayhuang
Should we be suprised that GP would show this kind of mismanagement and poor business judgement (holding/manufacturing better cells for one company than others) and questionable ethics? Althought this has nothing to do with ontrack performance, I sure hope IB holds to a much higher business standard than GP did. I guess I should be more specific and say GPNA. I dont know how ethical their offices are in Europe and Asia.

I am sorry-I am sure people are reading this going' "Ray-what the hell are you talking about?? Taken up Crack lately?" But I have my reasons.
Its called rewarding loyalty. GP is putting guys that stayed loyal to them ahead of guys that jumped ship. GP has not just been selling the new cells to the EU. There are one or two US matchers that are really on top of GP developents that have these new batch 3700's on the way.
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Old 11-11-2005, 03:07 PM   #745
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Quote:
Originally Posted by theisgroup
ahh, but that is only true in a static system. Remember resitance goes up as heat is produced. so as the motor get hotter in 6 cell touring cars because of the added weight and drive train, resistance also increases. You are correct at the start of the race, both R in the equation would be equal. but at any point after time zero, resistance will be higher on the 6 cell tc.

Can you tell me how much resistance changes from 75 to 160 degrees in an electric motor, or in the wiring going to the motor? I am willing to bet that its very, very little.
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Old 11-11-2005, 03:18 PM   #746
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Quote:
Originally Posted by beerbarron
Can you tell me how much resistance changes from 75 to 160 degrees in an electric motor, or in the wiring going to the motor? I am willing to bet that its very, very little.

very simple test. take your motor and put it on a dyno. and then just do several pulls until you have done this for 5 mins. I guarantee that your motor will not have the same power output and will not have the same rpm and torque ranges. or even better. take 2 motor you have and heat one of them up to 160 and hand your buddy the 75 degree one. why do you thing people spend $30-$100 on motor coolers. there is a forumal that I will look up that tells how much power it take to heat copper 1 degree. so that power that would got to drive the motor is being converted to heat. and I guarantee you that you will be suprise as to how much joules it take to heat coper from 75 to 160 degrees.

here is the calculation http://hyperphysics.phy-astr.gsu.edu...ic/restmp.html
and you see that the temp coefficeints of resistance for coper is 3.9 and your delta t is 85

you would basically get resistance final = resistance start * [1 + 3.9 * 85] or 332.5 time what the resistance the motor started at

not sure about you, but that sounds like a lot
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Old 11-11-2005, 03:26 PM   #747
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Quote:
Originally Posted by theisgroup
very simple test. take your motor and put it on a dyno. and then just do several pulls until you have done this for 5 mins. I guarantee that your motor will not have the same power output and will not have the same rpm and torque ranges. or even better. take 2 motor you have and heat one of them up to 160 and hand your buddy the 75 degree one. why do you thing people spend $30-$100 on motor coolers. there is a forumal that I will look up that tells how much power it take to heat copper 1 degree. so that power that would got to drive the motor is being converted to heat. and I guarantee you that you will be suprise as to how much joules it take to heat coper from 75 to 160 degrees.

I am not disagreeing with you about how much heat is created and the power that it robs. I am only asking if you know what the resistance change is for a warm vs cool motor? I have never measured it and am curios how much it is. If I have the time tomorrow I will measure how many ohms of resistance one of my Monster stock armatures has at room temperature then I'll put it in the oven at 180 or so and measure the resistance of the windings again. I could do the same thing for a length of 14awg wire, maybe I will. I still say it will be nill.
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Old 11-11-2005, 03:30 PM   #748
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Quote:
Originally Posted by AdrianM
Its called rewarding loyalty. GP is putting guys that stayed loyal to them ahead of guys that jumped ship. GP has not just been selling the new cells to the EU. There are one or two US matchers that are really on top of GP developents that have these new batch 3700's on the way.

The latest and freshest shipment that came into the US through GPINA has dropped in voltage and a few matchers that we deal with told us the GP3700s they got from Trinity are down as well. Maybe GP could be angry at Trinity since they buy some cells from IB but GPINA is owned by GP so they should get the best possible cells.


Oscar should send you a free case of cells since he has plenty and your a big GP supporter and seem to know what they are doing.
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Old 11-11-2005, 05:01 PM   #749
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Danny, I have to say I agree with you there. The GP3700s that we've been receiving as of late are also lower in voltage AND far lower in runtime then the ones I received early on.

FYI, these batches were gotten from different sources, so it wasn't just one bad batch from one supplier.
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Old 11-11-2005, 08:54 PM   #750
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So much for the theory of GP tweaking the cell. You should order cases from Orion they must be getting all the good ones.
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