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-   -   watt meter (http://www.rcuniverse.com/forum/electric-general-discussion-106/9356669-watt-meter.html)

racerxwest 12-24-2009 11:01 AM

watt meter
 
How do you use the watt meter to maximize your motor,esc and prop combination?? Thanks[:o]

tIANci 12-24-2009 01:54 PM

RE: watt meter
 
I use it to know how many amps my system is running esp when its a new set up or when I change props. If you want to 'maximise', what does maximise mean to you? Thrust, duration or speed for each amp drawn? If you mean any of the above then you will check RPMs (use a tach), measure thrust (a scale) and pitch speed (calculate RPM and prop pitch) based on the amps being shown on the meter. I hope I got what you mean right ...

cyclops2 12-24-2009 05:02 PM

RE: watt meter
 

It is great for finding a bad Brand new Battery, ESC, motor or prop.

Rich

racerxwest 12-24-2009 07:29 PM

RE: watt meter
 
Maximize to me is I want to fly the plane I have ( Little Toni ) at scale speed. Can't seem to get there as yet as I have tried various solutions but none has worked . Again thanks

tIANci 12-24-2009 09:56 PM

RE: watt meter
 
Racer ... is it the GP Little Toni? What is your current set up?

speedy72vega 12-25-2009 01:13 AM

RE: watt meter
 
A Wattmeter will help you in many ways.
First, it will allow you to check your current draw so you can make sure you're not overdrawing your motor, ESC, and battery.

Second, you can check the wattage output of your motor/prop combo to determine if it's correct for your plane. Example: You usually want at least 150 watts/lb for the type of higher speed sport/scale type flying you want to do. So, hypothetically, if your plane is going to weigh 2 lbs, you will want at least 300 watts. If your plane is going to weigh 5 lbs, you will want at least 750 watts, and so on. Different props will drastically affect draw, the meter lets you experiment with different diameter and pitch to see where your motor performs best.

Third, it is a good way to check a battery pack before flight to make sure it's charged. A full pack will usually be around 4.2v/cell, so a 3S pack is about 12.6v fully charged, a 4S pack is usually around 16.8v charged, etc.

Fourth, you can monitor voltage under loads to see if your battery packs have a high enough discharge rate so as not to get into the low voltage cutoff. The higher the C rating of the pack, the better it can sustain voltage under loads.

Hope this helps....

aeajr 12-25-2009 10:46 AM

RE: watt meter
 
Quote:

ORIGINAL: racerxwest

Maximize to me is I want to fly the plane I have ( Little Toni ) at scale speed. Can't seem to get there as yet as I have tried various solutions but none has worked . Again thanks
It is not clear to me what problem you are having and what you want from the wattmeter.

A wattmeter is a measuring device. It won't maximize or minimize anything it tells you the watts, amps and volts of your current configuration. YOU then change things to get the set-up you want.

So, what problem are you having? Please be VERY specific. What is preventing you from flying your Little Toni at scale speed?

szewang2805 01-15-2010 06:28 AM

RE: watt meter
 
i just found a watt meter which is good
check
http://www.swanghobby.com/gt-power-h...1-pr-1847.html

this is produced by GT Hobbies from China, any one tried it?


http://www.swanghobby.com/images/SAM003a1.jpg
http://www.swanghobby.com/images/SAM003a2.jpg

speedy72vega 01-15-2010 08:38 AM

RE: watt meter
 
I've never heard of that one personally, but it seems like it will do the job. I use an E-flite watt meter myself, got a good deal on it. There are many to choose from out there, one of the most popular is the Watts Up meter.
The one you linked to has a high capacity, and all the functions you need, let us know how it works out if you do get it.

hpiguy 01-30-2010 08:27 PM

RE: watt meter
 
HobbyKing sells a very reasonably priced watt meter here: http://www.hobbyking.com/hobbyking/s...dProduct=10080

I hear from other message boards that it's pretty good. I will be getting one as well with my next order.


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