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 Topics - General > Electronic Builders Workshop
Register Members List Wattflyer Extras Articles Search Today's Posts Mark Forums Read Social Groups

Electronic Builders Workshop Discuss how to build motors, ESC's, chargers, mixers, etc here

Thank you for your support (hide ads)
Reply
 
Thread Tools Display Modes
Old 11-28-2007, 05:33 PM   #1
diego
New Member
 
Join Date: Nov 2007
Posts: 2
Thanked 0 Times in 0 Posts
iTrader: (0)
Friends: (0)
Question Reversing polarity of brushed motor

Hello, I have a brushed DC motor, Electrifly T-370, which has an arrow on its label that shows the (preferred) direction of rotation. I want to reverse the direction, by reversing the polarity. However, I have been told that the efficiency of the motor is not the same as when the axis is rotating in the recommended direction.

My question is: is this true? If it is, by how much should I expect the efficiency to drop? Are there any other side effects?

Thanks a lot!

Diego.
diego is offline  
  Reply With Quote
Old 11-28-2007, 05:37 PM   #2
jonnyjetprop
Member
 
Join Date: Aug 2005
Location: Orlando, FL
Posts: 708
Thanked 14 Times in 13 Posts
iTrader: (0)
Friends: (0)
Default

It can be true. Brushed motors are timed. Most are not "neutral" but favor one directing over the other. Since brushed motors are a black art, I'd just suggest running it as is. Some of the more expensive motors can be chaged easily while the cheap can motors are basically forced by gripping the can of the motor and twisting it opposite the direction of rotation. How much?

John
jonnyjetprop is offline  
  Reply With Quote
Old 11-28-2007, 09:10 PM   #3
diego
New Member
 
Join Date: Nov 2007
Posts: 2
Thanked 0 Times in 0 Posts
iTrader: (0)
Friends: (0)
Default

Thanks for your advise.

Diego.
diego is offline  
  Reply With Quote
Old 11-29-2007, 04:23 PM   #4
rcflyair
Member
 
Join Date: Aug 2007
Location: Lavaca, Arkansas
Posts: 232
Thanked 32 Times in 32 Posts
Send a message via Skype™ to rcflyair
iTrader: (0)
Friends: (1)
Default motor

Run the motor the way it is intended and flip the prop.

rcflyair
www.rcflyair.com
rcflyair is offline  
  Reply With Quote
Old 12-01-2007, 05:02 PM   #5
pilotpete2
Pilotpete2
 
pilotpete2's Avatar
 
Join Date: Jan 2006
Location: NorthEast Kingdom, VT
Posts: 513
Thanked 21 Times in 21 Posts
iTrader: (0)
Friends: (0)
Default

Originally Posted by rcflyair View Post
Run the motor the way it is intended and flip the prop.

rcflyair
www.rcflyair.com
"Flipping the prop" is used to start gas and glow engines. Sorry, but a "pusher" prop is needed in this case, putting the prop on backwards won't do it. Pete
pilotpete2 is offline  
  Reply With Quote
Old 02-14-2008, 01:10 PM   #6
xplo5iv
Lawn Dart Specialist
 
Join Date: Oct 2007
Location: Herefordshire, UK
Posts: 11
Thanked 0 Times in 0 Posts
iTrader: (0)
Friends: (0)
Default

In addition the brushes may be designed mechanically in such a way that they need the motor to rotate in a particular direction. Reversing direction in such a case could damage the brushes quite quickly
xplo5iv is offline  
  Reply With Quote
Old 02-15-2008, 01:37 AM   #7
cyclops2
Super Contributor
 
Join Date: Dec 2005
Location: New Jersey
Posts: 1,956
Thanked 43 Times in 41 Posts
iTrader: (0)
Friends: (1)
Default If you have GOOD eyesight.

You can look into the brush end of a motor and see if the brushes are straight up & down. If they are, No brush damage will occur.
You can then reverse the leads on the motor safely.

To test for SPEED loss. Unhook the motor. Test run it each way with a single C or D cell. Sound the same ? close enough ? Go for it.

Rich
cyclops2 is offline  
  Reply With Quote
Reply

  WattFlyer RC Electric Flight Forums - Discuss radio control eflight > R/C Electric Topics - General > Electronic Builders Workshop

« 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 Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
dx6i reversing motor rotation, help! micro heli t-rex frame style Alpha_&_Omega Micro Sized Electric Helicopters 5 07-19-2008 07:05 AM
Brushed Motor Temperature dumorian Power Systems 9 05-08-2008 12:36 AM
Deans Polarity? Les Ward Beginners 20 08-21-2007 08:36 PM
Waypoint Motor shaft reversing Jollyroger Power Systems 2 05-05-2007 02:37 PM
Hacker Reversing motor shaft Pony Pirate Power Systems 1 09-03-2005 12:15 AM


All times are GMT +1. The time now is 05:06 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 0.16349 seconds with 31 queries