Scorpion Information

Here you will find various peices of information regarding our Scorpion range of Brushless motors and Electrionic Speed Controllers.

Scorpion Calculator
Scorpion Product Catalogs
Manuals
Motor Dimensions
Scorpion Motor Brand Comparison Sheet
HK4025 Trex 600 Install Instructions
Selecting the correct Motor, ESC and Batteries

FAQ:
What do the numbers on the motor mean?

Headspeed Calculator

http://heli.dacsa.net/CalculatorV2/

Scorpion Calculator
This wonderful program allows you to select any scorpion motor, power system, props and much more to give you very accurate expected figures like max effeciency, amps so much information you just have to check it out, all results are based on real tests not computer generated expected figures.

New 3.1V Version Click to Download

Selecting Motor ESC's and batteries

Scorpion ESC's are built different from other brands on the market. Most other ESC manufacturers build their speed controllers with no safety back-ups at all. The user is free to run the speed controller at greater than the rated current as long as they want, and if they push it too hard, the ESC goes up in a ball of flames.

After seeing this time and time again, the Scorpion designers decided to take a different approach. Instead of allowing the user to burn up ESC's, either on purpose or by mistake, Scorpion chose to add over-current, over temperature and short circuit protection in their ESC's to prevent this.

Where the problem now arises is in users that are used to running their other brand 60 amp ESC at 65 amps all day long, they find that the Scorpion 60 amp ESC shuts down, and figure that "There must be something wrong with it". In actuality, the ESC is doing exactly what it is designed to do, prevent the user from accidently damaging the ESC.

I have gone over this several times before, but I think that it is time to bring it up again, "Never Push Electronic Components to 100% Duty Cycle, EVER!" The ratings on electrical components are not like speed limits that can be exceeded without care or worry. The voltage and current ratings that are placed on components are there to let you know that if they are exceeded the part WILL be damaged. In might not catastrophically fail immediately, but it will be damaged. This damage might not cause the part to fail until later, but rest assured, it will fail.

As an Electrical Engineer whenever we built anything for the government or military, we could not exceed 50% of the rating of any part. This meant that we could run no more than 25 volts through a 50 volt capacitor, or more than 5 amps through a transistor rated for 10 amps, or 0.5 watts in a resistor rated for 1 watt. This insured that no component in the system would be over stressed and cause a failure of the assembly.

In commercial engineering, most people will not use more than 75% of the rated capacity of an electronic device. This is a very good practice, and should be heeded in our modeling ventures as well. Unfortunately, most people treat the voltage and current specs on parts like batteries, ESC's and motors like speed limits, and figure that if an ESC is rated for 55 amps, running it at 65 amps every once in a while won't hurt. Granted, it is normally OK to run products up to the max rating for short periods of time, but the overall running condition should be kept below that.

In a nutshell, I like to use the following guidlines for components:

Motors: Prop them to run at no more than 80% of the maximum rated current or power for continuous operation. For 3D type planes, where full throttle is only used in short 5-10 second bursts from time to time, running up to 100% rated current is OK, since most of the flight is run at 50 to 60% power. This would mean that if you have a motor rated for 50 amp max, don't run it at more than 40 amps. Likewise, if it is rated for 1000 watts of power, don't push it to more than 800 watts.

ESC's: Size them to be able to take, at a minimum, the maximum rated current of the motor, or so that the current drawn at full throttle is no more than 75% of the rated current for the ESC, whichever is higher. For example, if you have a motor that draws 60 amps at full throttle, use an ESC that is rated 80 amps.

Batteries: Size them so that you never pull more than 75% of the maximum rated current at any time, and never pull more than 80% of the rated mah capacity from the pack. In this case, let's assume you have a 2000mah 20C 3-cell Li-Po battery. At 20C, the max current for the battery would be 40 amps, so I would recommend not running this battery at over 30 amps of current draw. Also, you should not pull more than 1600mah of energy from the battery during each flight. By doing this you can easily get 100 cycles or more from your Li-Po batteries. If you exceed these values, don't be surprised when your batteries start going south after only 25 flights.

Hopefully that helps people understand the electronics a little better. I have worked with electronics for a long time, there are a lot of things that I just take for granted that many other people simply do not know or understand completely.

Motor Numbers what do they mean?

Each Scorpion motor has a 6 digit numbering system. For example: 2208/34. The first two numbers (22) represent the diameter of the stator (the fixed part in the middle of the motor) in millimeters. The second two numbers (08) represent the length of magnets (attached to the rotating case) in millimeters. The third set of two numbers (34) represents the number of wire winds, also called turns. In the HK Series and new S series of motors the last two digits or number of winds has been replaced by a Kv Number this is the motors RPM (Revolutions Per Minute) per 1 Volt of power. So for a 2208-1900kv for each 1 volt of power under NO load it will spin at 1900rpm.

When comparing the motors within any series (2208, 2212, etc.) there are several characteristics that you will notice. Motors with higher winds spin slower for every volt of electricity applied, they have a lower Kv (RPM/V). They spin a larger propeller at slower speeds and at a lower current than low turn motors. Motors with lower winds spin faster for every volt of electricity applied, they have a higher Kv (RPM/V). They spin a smaller propeller at higher speeds and at a higher current than high turn motors.

To determine the motor for your model: analyze the character of your airplane, is it sleek and fast, or a slower plane with a lot of drag? For the high speed airplane a low turn motor that spins a small prop fast would be the right choice. For a Trainer or Biplane with a lot more drag, a high turn motor that can spin a much larger prop and produce a lot of thrust at low speed is what you want.

Manuals

This is the information sheet that comes with each ESC.
COMMANDER 15V LBEC Manual
COMMANDER 15V LBEC V2 Manual
COMMANDER 26V SBEC Manual

Comparison Sheet

A reference sheet to help you choose the right size Scorpion motor. Each size Scorpion motor is listed with the corresponding sizes of other brands of motors.
Scorpion Comparison Sheet

Motor Dimensions

HK-3026
HKII-2208
HKII-2213
HKII-2216
HKII-2221
S3008
S3020
S3026
S3032
S-2205
S-2208
S-2215
S-4020
S-4025

HK4025 Trex 600 Motor Install

For those of you that have been patiently waiting for a motor for your 600 class helicopter, the new HK-4025 series has arrived! These motors are now up on the website, and are available for sale at only $129.99 each. These motors are rated for 2500 watts, and will take your 600 class helicopter to new levels of 3D power. The 4025 series motors weigh in at 320 grams, and feature a beefy 8mm main shaft that is ground down to a 5mm diameter at the pinion end to fit the standard pinion gears used on 600 class electric helicopters. These motors come with 4mm male bullet connectors already installed, and include a matching set of 4mm female connectors for your Speed Controller.

This motor is available in 3 different Kv values, 890Kv for 6-8 Li-Po cells, 740Kv for 8 to 10 Li-Po cells, and 630Kv for 10 to 12 Li-Po cells. For those of you that have not seen one before, here is a photo of the HK-4025-740 model.

 These motors measure 49mm in diameter, so if you are planning on using one in a Trex 600, you will need to trim away a little material on the side frames to make room for the motor. This actually removes more material that is needed, but cutting here leaves a much neater looking opening without any jagged edges. We have tested it and it does not seem to weaken the frames as the parts you are cutting out are full of cutouts anyway.