Manual for bpm motor.doc

Congratulations on your purchase of the Multiplex BL-480 brushless motor. Multiplex utilized the latest technology to provide a quality, high power brushless motor at an affordable price. Please read these instructions carefully before usage and store the m in a safe place so that you can refer back to them as needed in the future. 1. Specs 2. Applications 3. Installation 4. Wiring 5. Battery 6. Propeller 7. Motor temperature. 8. Gearbox 9. Maintenance 10. Warranty 11. Resources
Specifications
Chart 1
BL-480 4D
BL-480 6D
BL-480 8D
BL-480 4G
BL-480 6G
Stator Winding (6 slot)
Rotor Magnet (4 pole)
Neodymium
Neodymium
Neodymium
Neodymium
Neodymium
Motor KV (RPM/Volt)
Gear Ratio
No Load Current
Maximum Current
Maximum Power
250 watts
200 watts
150 watts
325 watts
275 watts
Maximum Motor Rpm
50,000 rpm
45,000 rpm
40,000 rpm
50,000 rpm
45,000 rpm
Current @ Maximum
Efficiency
Motor Weight
117 grams
117 grams
117 grams
117 grams
117 grams
Gear Box Weight
Motor Length
Gear Box Length
Prop Shaft Diameter
*Prop Range
4-5"
5-7"
7-9"
10-13"
12-16"
**Battery (Nicad/NiMh)
6 to 8 cells
6 to 10 cells
6 to 10 cells
8 to 12 cells
8 to 14 cells
**Battery (LiPo)
2 to 3 cells
2 to 3 cells
2 to 4 cells
2 to 4 cells
* Use smaller prop with higher cell count and larger prop with lower cell count
** Battery must be able to handle current draw of the motor.

Applications:
Listed below are the aircraft applications that we have tested each BL-480 series motor
with. These will give you an idea of what motor will be best suited for your particular
application. Note that these are just guidelines, and your application may vary depending
on several factors. Be aware the key to a good set-up is allowing the motor to operate
very close to its maximum efficiency current with the cell count and propeller. The more
cells that are used, the smaller the propeller needs to be to keep the proper current level.
More cells equal higher watts out but also increase the weight. A good rule of thumb is
that at least 50 watts per pound are needed for a plane to take off the ground and fly. 70
watts per pound are needed for mildly aerobatic airplanes, and 100+ watts per pound for
doing severe aerobatics. Watts in = Volts times Amps. I.E. Using an 8.4V battery with a
motor drawing 20 amps is 168Watts. Watts out = Volts times Amps times the efficiency
of the motor. The efficiency of the Permax BL-480 motors average about 80%.
Chart 2
Thrust Amps
Plane Type

Installation
Located on the front of the motor or gearbox are four 2.5mm holes. The direct drive
motors have two at 16mm and two at 18mm. The 16mm holes will fit a stock speed 400
motor mount. The geared versions have four holes spaced at 16mm only. For installation
is specific aircraft refer to the instruction manual of the aircraft.
(Show illustration)
Wiring/ESC
Brushless motors have three wires, instead of the usual two wires of a brushed motor.
These wires will be connected to the ESC. The motor will typically rotate counter
clockwise if the colors on the ESC match up to the motor wires. However, if you need to
the motor to operate in the opposite direction, swap any two wires; it does not matter
which two. Be sure to always use an ESC that is capable of handling the current draw of
the motor. Multiplex offers an ESC optimized for the BL-480 series motors and is
strongly recommended. However, any manufactures brushless ESC will work but be
aware some are programmed with higher timing which will affect the motors power
characteristics. Higher timing provides higher RPM with lower torque so a smaller
propeller should be used.
(Show illustration)
Batteries
As a general rule, for any high wing trainer type electric airplanes, you will want one
NiCad or NiMh cell for every 45-50 square inches of wing area, and for an aerobatic
plane, use one cell for every 35-40 square inches of wing area. We have found the 2/3A
size NiMh cells like the HeCell 1100’s and KAN 1050’s are a very good mate to the BL-
480 series motors due their low resistance and weight. Lithium Polymer (LiPo) batteries
can also be used, but there are a couple things to remember. First, you must make sure
that the cell you select will handle the current of the motor. You can find this out by the
“C” rating of the pack. For example a 3000mah LiPo pack with an 8C rating is capable of
producing 24 amps of current. This is really about the minimum you will want to use for
the BL-480 motors. Another factor is that one LiPo cell is equal to about 3.4 Nicad or
NiMh cells. Therefore, a two cell LiPo pack is about equal to a 7 cell Nicad/N iMh, and a
3 cell LiPo is about equal to a 10 cell Nicad/NiMh. Multiplex offers a full line of Lithium
packs, look for the Multiplex Li- Batt’s if you want longer runtime and reduced weight for
greater performance!

Propeller
The propeller is a vital component to the performance of the airplane. If the propeller is
too small you won’t get all the power from the motor. If the propeller is too big then the
current draw may exceed that of what the motor can handle causing the motor to overheat
and suffer damage. Chart # 2 lists combinations of batteries and propellers for each motor
that we have found to be effective. However, there are many other combos possible.
Chart #1 shows a range of propeller sizes and cell counts. Use the smaller recommended
size propeller with the higher cell recommendation and the larger propeller with the
lower cell count. Remember not to push the motor past the recommended maximum
amperage or you may damage the motor by overheating it.
Motor Temperature
While high temp Neodymium ma gnets are used in the BL-480 motors, it is vital not to
overheat the motor or they can be damaged. This is a big factor as to how much you can
push the motor. The motor temp should never exceed 200 degrees Fahrenheit. Ideally the
motor temp should be about 140 degrees after use if propped correctly. At 140 degrees
you should be able to put your finger on the motor for 2 to 3 seconds witho ut needing to
remove it. Again, keeping the motor current below the recommended maximum should
prevent overheating but other factors such as airflow and how long the motor is running
at that current need to also be considered. Typically full throttle is only used for take off
and maneuvers; if the motor is running at full throttle constantly just to fly the plane then
the heat will be much higher. If this is the case then the motor selected is probably not
powerful enough for the application.

Gearbox
Installed on the “G” version of the BL-480 motors is Multiplex’s heavy duty, planetary
gearbox. This high performance gearbox is made of high quality components for long
life and low drag. The gear ratio is 4.4-1. This means that for every 4.4 revolutions of the
motor output shaft, the gearbox output shaft rotates once. With this gear reduction, the
motor can swing a much larger propeller thus creating much greater thrust with lower forward speed. Maintenance
A great feature of the brushless motor is there is virtually no maintenance required.
However, care should be taken to keep the bearing clean and free of debris. If the
bearings do get dirty, it is best to blow them off with compressed air. Re-oil with a
VERY small amount of light household oil. Use only a small amount, as it can seep into
the motor. This should only be necessary after many hours of usage.
Warranty
Multiplex Permax BL-480 Brushless motors carry a Two -Year limited warranty.
Multiplex Warrantees:
1. Manufacturer’s defects. 2. Motor damaged during normal conditions.
Multiplex does not Warranty:
1. Crash damage or problems caused by neglect or abuse by the user. 2. Modifications to the motor of any kind. 3. Normal wear and tear. I.E. Components worn by use. 4. Application of improper voltage (more cells than recommended.) 5. Over-propping thus causing the motor to draw more current than maximum Warnings
Never
1. Disassemble the motor. 2. Exceed the maximum RPM, cells or current recommendations. 3. Allow the motor to get hotter than 200 degrees Fahrenheit. 4. Use a speed control with a lower amp rating than the motor is capable of. 5. Use spray oil on the bearings. 1. Make sure your batteries are fully charged before you fly. 2. Do a pre- flight check on the airplane to make sure all control surfaces are functioning correctly and move in the proper direction. 3. Let the motor cool to at least 10 degrees above the ambient temperature prior to 4. Make sure the throttle is in the low position and your finger and any other body parts are away from the propeller when plugging in the battery. 5. Be prepared for the propeller to “accidentally” start up. 6. Check the motor operation the first time without the propeller attached. Resources
There are many great resources on the Internet to help you with your set up and to learn
more about the great world of electric flight and brushless motors. Below is a list of
resources Multiplex highly recommends you check out.
Motor calculation programs:
http://www.motorcalc.com (Download free trial)
http://brantuas.com/ezcalc/dma.asp (Free on-line program courtesy of Diversity Model
Aircraft http://www.flydma.com )
While the Multiplex Permax BL-480 Brushless motors are not available in the motor
selections yet, hopefully they will be in the future. Until then you can select a motor in a
similar size and KV rating to give you a good idea of the set up. Try different cell counts,
types of cells, and propellers to see what performance you can expect. Remember to use
these programs only as a baseline, as your real world results may differ.
On-line magazines and forums:
http://www.ezonemag.com
http://www.rcuniverse.com
These are two great sources for R/C information. We strongly recommend becoming a
member of both and using the forums to search for topics of interest and also to post your
own questions as needed.

Source: http://www.mirax.cl/pdf/p34528.pdf