Voltage and current question

[plaviblue]

So is I am reading all the right, if rpm stays the same which is controlled by gearing,increasing the voltage should drop the amps.

Also, am going to buy a new 5-6cell batt tomorrow. Looking at the max-maps 6000 lipo, sound good?

[suicideneil]

Noooooooooooooooo! to the maxamps. There are so many better options, take a look around and see what the pros use (thats the guys on this forum ). I would suggest anything from rclipos.com basically.

RPMs are determined by motor kv (rpms per volt rating) and input voltage; gearing only alters wheel rpms. if you use a higher voltage with the same motor, you must gear down in order to reduce the load on the motor, and therefore maintain the same overall speed- efficiency will increase usually, and temps will decrease (longer runtime is also possible usually).

Originally Posted by suicideneil

Noooooooooooooooo! to the maxamps. There are so many better options, take a look around and see what the pros use (thats the guys on this forum ). I would suggest anything from rclipos.com basically.

RPMs are determined by motor kv (rpms per volt rating) and input voltage; gearing only alters wheel rpms. if you use a higher voltage with the same motor, you must gear down in order to reduce the load on the motor, and therefore maintain the same overall speed- efficiency will increase usually, and temps will decrease (longer runtime is also possible usually).

another option is to run a motor with a lower kv value

[suicideneil]

+1. Lower kv motor, plus that higher voltage and the same gearing will yield the same result, better even perhaps

[plaviblue]

I will check out the rclipo.com. I have fried 2 MMM already and there is not going to be a third. After talking to several people, it seems my batt did not have enough amps and the gearing was too tall.

Who makes a good onboard amperage monitor. I want to see what is going on in my truck.

[plaviblue]

Also, do you guys recomend balance charging or after charging with a blinky?

[tc3_racer_001]

i dont really see any point balancing AFTER charging. if they are out of balance youve already damaged them. charge AND balance would be my opinion

[MetalMan]

I balance at the end of the charge, and let it continue after the charge.

Differences in cells show up when there is less of a charge in them. So if you balance them early on in the charging process you could make the balancer work harder at the end of the charge than it would otherwise need to.

This is my theory anyways, and has proved successful for me.

[tc3_racer_001]

yes that makes sense. theres no point in balancing when they are less than 75% full. the cells will usually sort themselves out near the end, but i just plug them in and let the charger do its own thing :)

[myndseye]

<> as long as you don't have your voltage so high that you are revving into your motors inefficiency rpm range, the following statement is almost always true. In a truck with two available setups, if it's geared to go the same speed with each setup, the higher voltage setup will draw less current.

[jhautz]

Originally Posted by azjc

another option is to run a motor with a lower kv value

Originally Posted by suicideneil

+1. Lower kv motor, plus that higher voltage and the same gearing will yield the same result, better even perhaps

I agree fully with the lower kv motor option. A much better solution than just gearing down a motor spinning way faster than it needs too. No need to spin the motor much more than 30K rpm in my opinion.

Adding voltage and just gearing down to attain the same top speed can help a little if you are having ESC temp problems, but really wont do anything for you as far a motor temp problems in my experience. It may actually cause motor temp problems from what I have seen.

Getting a motor of the proper kv range for the voltage you plan to run is by far the best solution.

Higher voltage, lower motor kv, and similar gearing will product the best results for lowering current (amp) draw.

[lutach]

HV rules .