Scorpion Motors: Questions and Answers....
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Mar 26, 2007
, 11:36 AM
Joined Jan 2007
All of the 25 Amp ESC's that ship from now on will have the new BEC regulators installed.
The first order of 30mm motors shipped out yesterday. I should have them tomorrow, and within 1-2 days they will be up on the website available for sale. I am going to start listing them tonight, so check back in a day or two and they should be there.
I also have a shipment of more 22mm motors and replacement motor shafts arriving today. We also have a custom stamped aluminum stick mount arriving today, as well as extra threaded prop adapters and wobbly adapters.
The larger 45 amp, 55 amp, 70 amp, 90 amd and 110 amp ESC's are due in today as well, so you will be able to get a speed controller to go along with your new 30mm motor!
I also picked up some propellers and a few other accessory parts, so we will have those available as well.
All of these new items will be on the website by the end of the week. This is a pretty busy week for us here, since we are also exhibiting at the RCX show in Pomona, California this coming weekend on March 31st and April 1st, and have been working hard putting together new booth displays and getting product packed and ready to go.
That type of question does not have an easy answer. There are a multitude of factors that work together to determine the efficiency of a motor including input voltage, prop size, current draw, and the ESC used to power it. As input voltage increases, motor efficiency goes up, and as current increases, motor efficiency goes down. The efficiency varies from motor to motor across the line, but they are all pretty close to one another.
When running on 12 volts, all of the Scorpion motors have a peak efficiency in the 82% to 85% range. As with most brushless motors, this maximum efficiency point occurs when the motor is drawing around 30-35% of it's maximum rated current. When the motors are running at normal power settings of 75 to 80% of maximum rated current, they will run with an efficiency of around 70%.
There is another thing going on at Scorpion that I have not mentioned yet. We have a software engineer designing a custom motor efficiency calculator that is in the final stages of development right now. It has all of the parameters of the Scorpion motors in it with actual test data, so in the future, you will be able to pick a motor, then pick a prop, and the program will tell you exactly how many RPM it will turn, how much thrust it will produce, how much current it will draw, the motor efficiency at that point, prop pitch speed, actual prop output power and estimated motor operating temperature! It will also display all of the motor parameters including Rm, Io, Kv, and motor weight as well as a photo of the motor so you can see what it looks like.
As a bonus, the program will also have many user selectable options, so you will be able to display the values in English or Metric units, compensate for altitude and temperature, change the chart colors and even save settings of prop combinations that you like. You can even print them out to compare one set of values against another!
Once it is completed, this Scorpion_Calc program will be available as a free download on our website. It is a fairly small program, and just under 1MB file size, so even if you have dial-up internet, it will only take less than a minute to download. The program is just about finished now, and I just got a new release of it today to test and play with, so it should be available for distribution very soon.
More good stuff coming every day!