AERORICH73

aeajr: I am interested in learning more about the electric power systems, and how all the components are connected. If I have an AXI 2204-54 brushless motor that has the three wires for connections, just what are the polarity identifications for + and -, and why are there three wires going to the ESC? I have delt with small two wire motors which had only the + and - connections. The second question is about changing motor rotation. I am aware of reversing the + and - wires, but the extra wire confuses me. Would appreciate your help in clearing up my confusion.

aeajr

My Feedback: (2)

The two wire motors, red/black, are typical brushed motors where a mechanical commutator is used to change the polarity of the coils. Switch the wires and the motor runs the other way. A 2 wire electronic speed control, ESC, pulses the power to the motor to control the speed of the motor. This is more efficent than varying the voltage using a resistor.

The three lead motors, which may all be the same color, are typical brushless motors. The ESC does the polarity switching via electronics. If you swap any two wires, the motor will run in reverse. Since there is no mechanical drag, not brush or commutator wear, the brushless motors tend to be more efficient and have a much longer maintenance free life.

The trend is all toward brushless these days which is a good thing. The motors and ESC are more expensive than the brushed versions, but the power output and life is so much better that is worth it, and the prices are coming down fast.

Orakal-1

Hi Ed,

It certainly has been a positive journey for me reading through the much needed and simply explained lessons, trying to comprehend the complete 'book' to unravelling the secrets of the 'mechanics' behind e-flight electrics. For me it has opened the door into an exciting new dimension in modeling. Thanks Ed for your insight and fairdinkum knowledge on a very difficult to understand subject, especially for the 'newbee' who has yet to decide whether to go glow, gas or e-flight.

I have been flying low winged glow powered planes for about a year now as I just couldn't get my head around the electric mystery, but I'm now building a 'Zivko' Edge 540 49" wing span electric 3D plane (from Qx models ?) for the first time and about to install the electrics. Although there are a few photos they are not very helpful, and would appreciate very much if you would include in your writings a simple sketch or photo showing how the motor connects to the electrics. I'm sure this would greatly assist in the understanding, as me being a mechanical engineering draftsman, one diagram or illustration would be worth more than a thousand words.
for example: How does it all connect together,

MOTOR to ESC to LiPo BATTERY to BEC to RECEIVER (which connection etc)

Many thanks again, Ed, in advance.

JH, Brizzy, Australia.

aeajr

My Feedback: (2)

JH,

Glad you found the book helpful.

Electric connection is very very simple, so don't over think it. I will look to see if I have a photo. I thought I had provided a link to photos/diagrams, but perhaps someone else will provide one or a diagram.

How does an electric set-up differ from glow/gas/glider? From a receiver and servos point of view, there are no differences from a glow, gas or glider set-up. Servos plug into the receiver, same as always.

Delete the throttle servo and the receiver battery.

Add the Electronic Speed Control/BEC which is normally a single device with three sets of wires coming out the sides.


For small electrics, typically with 4 micro servos or less, the ESC becomes the hub for all power. The connections are:

* One for the flight/motor battery
* One for throttle/power to the receiver - Goes into the throttle slot on your receiver
* One to the motor.

So your ESC plugs into the receiver in the slot where your throttle servo would have gone. Not only does it control the motor speed but it delivers power to the receiver for the servos. Simple! This one connection serves the purpose of the throttle servo AND the receiver battery which frees up a slot on your receiver.

The motor plugs into the ESC and the battery plugs into the ESC. Normally the connections are marked on the ESC which eliminates any confusion. Normally the battery and motor connections are different so you can't confuse them.

I know it is not a photo, but how did I do?

pontiac6000le88

hi Ed,
happy new year to you and family.

i have a question about the brushless motor hook up to esc.

this is the motor and esc i have.
motor - http://www.hobbyking.com/hobbyking/s...dProduct=5432#



esc - http://www.hobbyking.com/hobbyking/s...idProduct=2164

the question is the 3 wires in motor are all black, which one to which will go to the esc?


question 2 is i purchase a charger from hobby city
http://www.hobbyking.com/hobbyking/s...idProduct=7028

am i suppose to just hook up both balance plug and discharge plug to charger? the battery i have don't come with dean plug. ( i need to redo the plugs). but charger keep saying battery disconnect when only balance plug is in? no manual or whatsoever with this charger. mike

Orakal-1

Hi Ed,
A happy new year to you and yours,

Many thanks for your timely reply. It took several reads before the 'light turned on.!! But at the end, all was revealed.

My setup is slightly different than the one you described in that the ESC doesn't have a buit in BEC, it has 2 cylinders I think are capacitors, and has 4 sets of wires.
1 set of 3 black ones for the motor, and of course the other set of 2 thick ones, red and black with a deans connector, for the battery. All good so far, simple.
From the deans connector another set of 2 very thin wires, red and black which connect to the separate U/BEC, which then plugs into the Aux2 of the Rx and the 4th set of 3 wires with the +ve cable disconnected, this plugs into the Throttle of the Rx. so, in the words of the immortal Bard, Ed, how did I do?

The reason for all my confusion was that I bought the new ARF plane from a fellow modeller together with a big bundle of wires, motor, ESC & U/BEC, not knowing what they were for, with miscellaneous bits and pieces, props, batteries etc,etc, ...who was about to go on a months holiday overseas. Also I had information overload which prompted me to contact you to resolve the problem.

Also with the help from good folk at the local model shop, the Tx is fully programmed and the plane WILL fly this weekend. Thanks to you all.
What a marvellous forum this is.

many, many thanks again Ed, for your patient assistance,

Kind regards,

John H

aeajr

My Feedback: (2)

When hooking up a brushless motor, the procedure is easy. If the wires are color coded, follow the colors. If they are not, then do it at random and test the motor. From the pilot's seat, the motor should run clockwise for normal rotation. If it runs the other way, switch any two wires and it will change direction.

As for the charger, READ THE INSTRUCTIONS. If you did that, then tell us what they say and what you don't understand.

RTFM, read the F..... friendly manual.

pontiac6000le88

ed,

i have another question about hookup the servos to my receiver. I have spektrum AR6100e receiver. These are the markings on the terminals.
AUX1
Gear
Rudd
Elev
Alie
Thro
Batt

I would like to know what servo plug to which terminal. Right now i need to have 4 controls. ( throttle, elevator -left and right, and rudder) My question is i believe i need 2 servos for the elevators, am i suppose to use a Y-split for 2 servos and plug to terminator "Elev". However, hookup like this will make those left right elevators go up and down the same time, it should not be like that?

in my dx7 radio, there are few switches ( aux2, elevator D/R, Flap mix etc) on top ( other than the regular control stick) what exactly they suppose to do? I read the manual and seem there is no explaination on those switches.

mike

aeajr

My Feedback: (2)

OK, we have now left the topic of electric flight and moved into the are ofyour specific model of radio.Your questions would be just as valid for a glow plane or a glider. That is beyond the scope of this dicussion. I would suggest you go to one of the many discussions about the DX7.

However I would love to know what plane has dual elevators and rudder. What kind of plane is that?

If Imay offer an observation, asking about how to set up a plane while keeping the name and type of plane a secret is the best way I know to get wrong answers and lots of them. Tell us the name of the plane ANDprovide a link to information about it. If you don't do this, then we guess about the plane and give you answers based on what we guessed. That will not help you.

aeajr

My Feedback: (2)

pontiac6000le88

Thanks for sending me the PM.  For the benefit of those who read this tread, pontiac6000le88  is not setting up twin elevators, he is setting up elevons, which are different from twin elevators.  These are controlled using an Elevon or Delta Wing mix on the computer radio.  Some standard radios also have an elevon or delta wing mix built in.   Or, if your radio lacks an Elevon mix, then you can buy a small device called an elevon mixer and it will do the mixing.

SARBoy

aeajr,

Great thread. Lots of info, all in one place and very nicely explained.

Do you have any experience with edf power trains?

If so, is there any difference to the basics described in you ebook, i.e. fan pitch, number of blades etc?

Thanks

Tom

aeajr

My Feedback: (2)

Sorry, I have no experience with EDF systems.

SARBoy

aeajr,

No problems, the search for info continues. Thanks again for a great thread.

Tom

yoyo5

Ed  would the airobird  3 be a good choice for my first  plane because
 after loking at it and reading your  review i think it would be a good plane



                                                                                                                          [8D]

aeajr

My Feedback: (2)

Yes!

SteelersRule!

what a tremendous amount of information! Thanks to all for the contributions.

Lou

SteelersRule!

any particular brands of electric motors preferred out there? also brushless or inrunners?

Thx

Lou

nate691023

I have a Goldberg Electra glider. The weight is is a little over 3.5 pounds..
What i am trying to do is. Put a Brushless motor and ESC in it and get rid of the old 550 motor and BEC and the gear box.
I am more of a slow flight. But I do not mind a little extra power to get some speed.
I was wondering if you could help me find the Right Brushless motor and ESC for it.
Plus what props to use!






I will be using a folding Props(10/612/8.)
I can get more Folding Props if needed!

aeajr

My Feedback: (2)

It would appearyou have not read any of the book. This thread is a book on electric flight. I suggest you read the chapters, then post the combinations you think would work and why. Then we can help you.

This is a learning discussion. Why not take a little time to read and learnrather than ask us to do it for you.I think you will find that a much more rewarding experience.

nate691023

aeajr

My Feedback: (2)

Nate,

Glad you found Motocalc.  

Continue your reading and more and more of the electric power model will make sense.  The more you understand the more Motocalc will make sense.

cloudwalker

Hi, can you help please.? Ihave the parkzone f4f wild cat that came with an 18 amp esc and brushless parkzone 480 sized 960 Kv outrunner motor. My question is, can I use my batteries which are 2200 35 c lipos or will they burn somthing out ? this is my first attempt at electric flight. Hope you can help. Thank you . Bill.

aeajr

My Feedback: (2)

Have you read the chapters?

What is the battery normally used in this aircraft?

What would lead you to believe these battery packswould burnsomething out?

ombudsman

There is something in the text I just can't wrap my mind around. The statement is made, if I understand it correctly, that when evaluating a power system that operates with, for example, 2S or 3S, the largest prop size listed is to be used with the lowest voltage battery pack. It seems, intuitively, that the bigger prop would put more load on the motor and draw more amps. Does the larger prop keep the motor from over-speeding or what? Have I misunderstood the whole concept? Could you elucidate for me, a person operating with a very deep well of ignorance concerning matters electric? Thanks.
Dave

aeajr

My Feedback: (2)

Kv = RPM per volt.

Higher voltage - higher RPM

If you put the biggest prop on the highest voltage you are likely to overload the motor since the highest voltage will spin the motor faster, or draw more and more amps trying to hit that speed. Result - burn out motor, ESCand/or battery.

EXAMPLE

The propeller places the load on the motor. The wider or the deeper the prop
the greater the load on the motor. By matching the propeller to the motor
and the load you want to place on the motor you can control how much the
motor draws.

For example, I have this motor in one of my 2M planes:

Rimfire 35-30-1250 Brushless Outrunner Electric Motor
http://www3.towerhobbies.com/cgi-bin...&I=LXLWU0&P=ML

Aircraft Application:
75-100 Watts Per Pound
Trainer & Sport Performance Weight Range: 3.3-4.4lb
100-150 Watts Per Pound
Aerobatic & High Speed Performance Weight Range: 2.2-3.3lb
Over 150 Watts Per Pound
3D & Extreme Performance Weight Under 2.2lb

Motor Diameter: 1.38" (35mm)
Motor Length: 1.18" (30mm)
Shaft Diameter: .16" (4mm)
Shaft Length: .65" (16.5mm)
Lead Length: 3" (76mm)
Connectors: Bullet type, .14" (3.5mm) diameter
Max. Constant Current: 30A
Max. Surge Current: 35A
Max. Constant Watts: 333W
Max. Surge Watts: 390W
No Load Current: 1.2A
Input Voltage: 11.1V
RPM/V (kV Rating): 1250
Weight: 2.5oz (71g)
Suggested Propeller Size: 10x7E

If I run it on a 10X7 prop with a 3S lip, it crankEd about 290 watts at about
28 amps.

If I put an 11X8 on it it will go to over 400 watts which is too much for
this motor. It would burn it out.

However if I go to a 2S lipO on that same 11X8 prop it will run at about 150
watts, around 20 amps.

I fly it with the 3S 10X7 and it will go almost straight up. I use that for
contests but I only have one 3S pack that can handle the amp load.

I also fly it with the 2S 11X8. I get about a 45 degree climb. I have 4 2s
packs that I can use with this prop.

So, as you can see, I can tune the load to the kind of flying I want to do
and the kind of battery pack I want to use. All work and all work with the
same motor.

How do I know all this? I put a wattmeter on the motor and measure what it
is doing with the different props and different battery packs.

How was that?


Still don'tget it?

You have a 3 speed bicycle. higher the gear = bigger the prop

Youare the motor and you have an efficent speed range and you are only so strong.

You approach a big hill from level ground. You want to keep the pedals going ata constant, efficent speed. Do you gofor the highest gear or alower gear? What happensif you select too high a gear? Youoverload and have to get off and walk. In the case of your motor, it overheats and fails.