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Old 10-18-2007, 03:53 PM   #1
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Default 4.8v or 6.0 volt

regardless of what servo or receiver i'm using?

whick rx pack will provide longer runtime
a 4 or 5 cell, or the same runtime? considering they have the same capacity
and the fact that my servos will be slower and less torque

just wondering from all weight freaks in my club
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Old 10-18-2007, 03:57 PM   #2
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Originally Posted by Seisick View Post
regardless of what servo or receiver i'm using?

whick rx pack will provide longer runtime
a 4 or 5 cell, or the same runtime? considering they have the same capacity
and the fact that my servos will be slower and less torque

just wondering from all weight freaks in my club
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Old 10-18-2007, 04:40 PM   #3
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With the same Mah, if you consider just voltage, the higher voltage will last longer. This is because the servos won't use up as much voltage because they don't have to work as hard as they would with lower voltage. Think of it as horsepower. With more horsepower, the engine doesn't have to work as hard to move the car which will increase mpg as well. I would think there would be a big difference in the performance of the servos too. If you're used to them running fast, switch to lower voltage to save a gram, then smash the wall because the servo didn't turn fast enough, it's not really worth it. Plus, you spent all that money on that motor and don't you want to see it run to it's full potential? With a slow servo, it won't and that gram you saved on a battery is causing you to get smoked out of the corners.
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Old 10-18-2007, 05:59 PM   #4
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but won't faster and torquey drain more? forget about the performance on the servors, just strict to which will provide more run time!
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Old 10-18-2007, 07:46 PM   #5
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With the same Mah, if you consider just voltage, the higher voltage will last longer. .
actually i believe the opposite to be true. with the higher voltage available the servo will draw more current (servo is a constant resistance, so an increased voltage means higher current flow) it seems non-intuitive.

despite the reduced run-time, the increased speed and torque will more than offset any run-time disadvantage.
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Old 10-19-2007, 03:15 AM   #6
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actually i believe the opposite to be true. with the higher voltage available the servo will draw more current (servo is a constant resistance, so an increased voltage means higher current flow) it seems non-intuitive.

despite the reduced run-time, the increased speed and torque will more than offset any run-time disadvantage.
so basically if you have enough juice on your servos and assuming that they re not digital (more currente draw right?) a 4.8v will provide more runtime! i guess this question could be easily answered if somehow i could now what is the draw in mah per hour at 4.8 or 6, the same info for a servo for example torque and speed at 6v.

thanks
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Old 10-19-2007, 07:34 AM   #7
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Go with LiPo packs, they work great, constant voltage (with the regulator), light weight, and more capacity for weight ratio.

son buenas (they are good)

the most import thing, HAVE FUN with the experiments
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Old 10-19-2007, 07:55 AM   #8
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Originally Posted by Seisick View Post
so basically if you have enough juice on your servos and assuming that they re not digital (more currente draw right?) a 4.8v will provide more runtime! i guess this question could be easily answered if somehow i could now what is the draw in mah per hour at 4.8 or 6, the same info for a servo for example torque and speed at 6v.

thanks
hmm, something i forgot to consider, the servo motor's draw is proportional to the torque or it's load. so if you have enough torque with the lower voltage, and you don't change driving style.(don't use the additional torque somehow)

maybe someone has done an experiment, but i think the answer is 'same torque= same runtime' , 'use the higher torque= reduced runtime'.
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Old 10-19-2007, 08:33 AM   #9
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Go with LiPo packs, they work great, constant voltage (with the regulator), light weight, and more capacity for weight ratio.

son buenas (they are good)

the most import thing, HAVE FUN with the experiments
oh yeah at $2.9 the 4 pack of 750mah duratrax at tower should be enough to do the experiment, on the other hand, if lipos were to be used without regulator that would be a different story, though some use it directly on their ko rx and servos with no problems whatsoever

lipos son caras jeje
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Old 10-19-2007, 09:07 AM   #10
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Lipo is not my choice. We do drive in the rain and I have seen many regulators failing with one drop of water inside. Currently 2/3A cells are very good, I run the IB1400 cells and can run up to 1 hour with no problems on 6v with digital servo's.
These cells are yet available with up to 1600mAh (Team Orion)
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Old 10-19-2007, 11:21 AM   #11
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Lipo is not my choice. We do drive in the rain and I have seen many regulators failing with one drop of water inside. Currently 2/3A cells are very good, I run the IB1400 cells and can run up to 1 hour with no problems on 6v with digital servo's.
These cells are yet available with up to 1600mAh (Team Orion)
yep, in currently using the smc 1200 6v, for over a 16 months now and it provides more than an hour to my digital servos, i just discharge it to 1.1v per cell once a month and so far so good, just wondering cuz if i could save 20g on that pack if i convert it to 4.8v, i've got too much performance already on my servos
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Old 10-19-2007, 09:16 PM   #12
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Well, i just switched to 6v myself, but i haven't had the chance to really test it. However, from what i gather 6v doesn't really matter if you are running AM and people say it typical last about an hour or two Still, its hard to believe that a 6v 1400mah could outlast 4.8v 2500 mah (energizers cost about 10 bucks, actually cheaper than 6v stick battery). Regardless, I remember running 4.8v 2500mah for about 5 hours (not straight of course). I can't tell you how much power was left out of the pack as I didn't have a volt meter.
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