Wattflyer RC Network: RC Universe :: RCU Magazine :: RCU Forums :: RCU Classifieds :: RCU User Reviews :: RCU YouTube
Home Who's Online Calendar Today's Posts RealTime Post Spy Mark Forums Read
Go Back   WattFlyer RC Electric Flight Forums - Discuss radio control eflight > R/C Electric Power - Batteries, Chargers, ESCs and More > Power Systems
Register Members List Wattflyer Extras Articles Search Today's Posts Mark Forums Read Social Groups

Power Systems Talk about motors, ESC speed controllers, gear drives, propellers, power system simulators and all power system related topics

Thank you for your support (hide ads)
Reply
 
Thread Tools Display Modes
Old 09-22-2014, 06:49 PM   #1
CHELLIE
Super Contributor
 
CHELLIE's Avatar
 
Join Date: Oct 2006
Location: Hesperia, So. Calif
Posts: 18,597
View CHELLIE's Gallery13
Thanked 2,162 Times in 2,070 Posts
Club: Chino Renegades RC Flying Club
Awards Showcase

Scratchbuilders Award  Scratchbuilders Award  Ambassador Award  100mph Speed Demon 
iTrader: (4)
Friends: (311)
info How To Advise on Multi Motor Aircraft Setup

Hi Everyone Hopefully This Thread Will help others out there in Setting up Their Multi Motor Powered Aircraft, I Know I ran into issues with a twin Motor Plane that drove me Crazy trying to figure out the problems, Hopefully this Thread will Point people in the right direction to get it Right the first time, Please add any info that will help Others to Succeed in getting their Multi Motor power system set up Correctly.

Thank You Everyone.

I may be getting Older, But I Refuse to grow Up I am Having to much Fun to Grow Up LOL
CHELLIE is offline  
  Reply With Quote
Old 09-22-2014, 06:52 PM   #2
CHELLIE
Super Contributor
 
CHELLIE's Avatar
 
Join Date: Oct 2006
Location: Hesperia, So. Calif
Posts: 18,597
View CHELLIE's Gallery13
Thanked 2,162 Times in 2,070 Posts
Club: Chino Renegades RC Flying Club
Awards Showcase

Scratchbuilders Award  Scratchbuilders Award  Ambassador Award  100mph Speed Demon 
iTrader: (4)
Friends: (311)
Default

Here is what I have learned so far from my Mistakes.

1. Use ESC from the same vendor, and same Amp Value.

2. Use Motors from the same Vendor, same size and KV.

I may be getting Older, But I Refuse to grow Up I am Having to much Fun to Grow Up LOL
CHELLIE is offline  
  Reply With Quote
Old 09-22-2014, 07:00 PM   #3
solentlife
Super Contributor
 
solentlife's Avatar
 
Join Date: Oct 2010
Location: Ex UK Brit now in Latvia west coast - Ventspils
Posts: 6,111
View solentlife's Gallery47
Thanked 261 Times in 258 Posts
Club: Founder Member Ventspils RC Club. Ex Waltham Chase and Meon Valley Soaring.
Awards Showcase

Scratchbuilders Award  Scratchbuilders Award  Outstanding Contributor Award  125mph Speed Demon 
iTrader: (0)
Friends: (15)
Default

a) Regardless of motors - use SAME ESC brand and power range based on the highest power motor in the set.

b) Linear BEC's can all be connected without problem and in fact will allow a greater amp load to be covered. No need to isolate down to one only.

c) Switching BEC's cannot be all connected to one Rx ... they interefere with each other - and you need to isolate all but one ... leaving one only to power Rx. You could fit a 'battery-backer' and have another BEC connected to that - then in event of first BEC failing - the BB will auto switch instantly to the second BEC.

d) It is generally advised to have props contra rotating to cancel out torque - BUT it is not essential and as long as both motors are running same - you would not know difference.

e) Many twins in model form will not fly single engine out ... it takes too much rudder / yaw authority to do it well. You may be able to fly a low speed descending landing pattern though.

f) Twin's do not mean double speed. You are still limited to PITCH speed ... but your acceleration should be better. What you may get is a small increase in speed as the twin set-up will reduce drag losses by way of increased power.

As I think of others - will post up !

Cheers
Nigel

222kph PKJ,EDF Concorde, Mini4,Mig3,T45,PKJ twin,ME109,Edge540,Cessna182,Skymaster Biplane,F15,F16,Badius,Ultimate,SE5,Qbee10,450 Heli,V911,J3 Cub Founder 9x forum: http://groups.yahoo.com/group/Flysky_RC_radio/
- Subscribe my Youtube: "solentlifeuk"
solentlife is offline  
  Reply With Quote
Old 09-22-2014, 07:27 PM   #4
fhhuber
Super Contributor
 
fhhuber's Avatar
 
Join Date: Mar 2013
Posts: 2,171
Thanked 216 Times in 207 Posts
iTrader: (0)
Friends: (1)
Default

Electric does NOT eliminate the chance of single engine out. Many failures are possible including throwing the prop & adapter off the motor.

Avoid turning toward the dead engine side.

Best response to loss of one is usually to shut down the other. (4- can usually fly Ok with one out) Slowly add power to a maximum of what requires 50% rudder to maintain a straight path.

Some twins handle loss of one better than others there are a few where all you'll notice is a loss of max speed.
fhhuber is online now  
  Reply With Quote
Old 09-22-2014, 07:46 PM   #5
kyleservicetech
Dennis V
 
kyleservicetech's Avatar
 
Join Date: Apr 2008
Location: Wisconsin, USA
Posts: 8,048
Thanked 698 Times in 680 Posts
Club: www.racinercclub.com (I'm the newsletter editor)
Awards Showcase

Outstanding Contributor Award  3kW  2kW  100mph Speed Demon 
iTrader: (1)
Friends: (20)
Default

Originally Posted by CHELLIE View Post
Here is what I have learned so far from my Mistakes.

1. Use ESC from the same vendor, and same Amp Value.

2. Use Motors from the same Vendor, same size and KV.
ESC uBEC's can all be used at the same time. BUT, they must be isolated from each other. A simple Shottky diode in the ESC red wire leading to the receiver will do the trick.

I can provide a source for the 10 Amp Shottky diodes and wiring diagram if desired.

DennyV
Retired and the days are just too short, busier than ever!
kyleservicetech is offline  
  Reply With Quote
Old 09-22-2014, 08:05 PM   #6
pmullen503
Member
 
Join Date: Mar 2011
Posts: 848
Thanked 71 Times in 70 Posts
Awards Showcase

Scratchbuilders Award 
iTrader: (0)
Friends: (3)
Default

Originally Posted by CHELLIE View Post
Here is what I have learned so far from my Mistakes.

1. Use ESC from the same vendor, and same Amp Value.

2. Use Motors from the same Vendor, same size and KV.
My DO-335 has two different size motors and two different ESC's. Only one has a BEC. That setup has worked fine for years. The problems you had with the Cessna were weird. But for side by side twins, use the same motors and ESC's. If you are running more than a couple servos or more than 3s, use a switching BEC. Most linear BECs have a limited capacity.

You can separate and reduce the loads on linear BECs by running two receivers with separate circuits. I've used a pair of cheap Spektrum clones (DSM2), one in the wing and one in the fuselage to simplify assembly and disassembly. Just run one of the throttle connections to the second receiver for power.

Contra rotating props help especially with ground handling for tail dragging twins and with aerobatic aircraft when trying to get matching right and left roll rates.

Many TXs can handle differential thrust programming on two motors. This is great for seaplanes and tail dragging twins when taxiing.

It's never too late to have a happy childhood.
pmullen503 is offline  
  Reply With Quote
Old 09-23-2014, 04:58 AM   #7
CHELLIE
Super Contributor
 
CHELLIE's Avatar
 
Join Date: Oct 2006
Location: Hesperia, So. Calif
Posts: 18,597
View CHELLIE's Gallery13
Thanked 2,162 Times in 2,070 Posts
Club: Chino Renegades RC Flying Club
Awards Showcase

Scratchbuilders Award  Scratchbuilders Award  Ambassador Award  100mph Speed Demon 
iTrader: (4)
Friends: (311)
Default

Thank You Everyone for your Input, I am Sure this Information will help a lot of People with their Multi Motor Aircraft.

I may be getting Older, But I Refuse to grow Up I am Having to much Fun to Grow Up LOL
CHELLIE is offline  
  Reply With Quote
Old 09-23-2014, 12:00 PM   #8
Kvar
New Member
 
Join Date: Sep 2014
Location: Brisbane Australia
Posts: 9
Thanked 1 Time in 1 Post
Club: Tingalpa
iTrader: (0)
Friends: (1)
Default Multi

For what it is worth I set up my multis so that the prop tips on either side turn into thecockpit. Dont know where I got that idea done it for years even back in my free flight days. Oh yes, I set up the left snd right inner motors on one setup and the left and right outers on another.
Kvar is offline  
  Reply With Quote
Old 09-23-2014, 12:56 PM   #9
fhhuber
Super Contributor
 
fhhuber's Avatar
 
Join Date: Mar 2013
Posts: 2,171
Thanked 216 Times in 207 Posts
iTrader: (0)
Friends: (1)
Default

top going toward center has the torque/P-factor oppose the offset thrust if you lose the other motor.

This is used on most aircraft that have counter-rotating props, with the notable exception of the P-38 which has the props rotate backward due to an unusual instability issue.
fhhuber is online now  
  Reply With Quote
Reply

  WattFlyer RC Electric Flight Forums - Discuss radio control eflight > R/C Electric Power - Batteries, Chargers, ESCs and More > Power Systems

« Previous Thread | Next Thread »

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
EDF setup for control line model A-10 variant jccrall Electric Ducted Fan Jets 45 09-24-2013 05:40 PM
Setup help with foam ducted fan F16 danauti1 RC Radios, Transmitters, Receivers, Servos, gyros 13 06-03-2012 04:23 AM
PArkzone Radian Pro setup (DX7 + AR6200) Fulanito_uk Hi-Performance and Sailplanes 5 09-22-2011 05:58 AM
160 mph Setup Question twinbrother2010 Hi-Performance and Sailplanes 13 07-25-2011 05:15 AM
Need help with complete setup. KenSue Power Systems 9 01-29-2011 01:36 AM


All times are GMT +1. The time now is 06:55 PM.


Powered by: vBulletin
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Copyright 2005 WattfFlyer.com
RCU Eflight HQ

Charities we support Select: Yorkie Rescue  ::  Crohn's & Colitis Foundation



Page generated in 0.20821 seconds with 37 queries