ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals

ECN Shout Chat
Top Posters(30 Days)
Admin 16
Recent Posts
fuse rejectors
by gfretwell. 03/23/17 01:12 PM
Another Forum Update
by Admin. 03/22/17 03:04 PM
Dining room plugs
by watersparkfalls. 03/21/17 10:31 PM
by jraef. 03/21/17 09:13 PM
WEG CFW-11 Frequency Inverter
by jraef. 03/21/17 08:50 PM
New in the Gallery:
SE cable question
Popular Topics(Views)
231,263 Are you busy
165,977 Re: Forum
160,489 Need opinion
Who's Online Now
0 registered members (), 49 guests, and 12 spiders.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate This Thread
#129049 - 07/06/04 03:01 PM * * * AC commutator motors* * *  
nader  Offline
Junior Member
Joined: Jul 2004
Posts: 1
Please can show me by drawing who can I change the diriction of the AC commutator motors.

Thanks allot.

Tools for Electricians:

#129050 - 07/06/04 03:39 PM Re: * * * AC commutator motors* * *  
pauluk  Offline
Joined: Aug 2001
Posts: 7,520
Norfolk, England
Hi Nader,

Commutators are found on DC motors, not AC (although you could include the "universal" AC/DC types as are found in some appliances).

You can reverse the direction of rotation of such a motor by swapping the connections to the armature (i.e. those connections which go via the commutator) while leaving the field connections unchanged, or vice versa.

If it's a small permanent-magnet motor (which has no field coil) then just reversing the connections of the DC supply will suffice.

[This message has been edited by pauluk (edited 07-06-2004).]

#129051 - 07/06/04 04:24 PM Re: * * * AC commutator motors* * *  
aland  Offline
Joined: May 2004
Posts: 186
United Kingdom
Yes you can have Commutators on A.C. Motors,
Not so very common now in the age of the inverter. Mostly used for variable speed aplications where the brush gear is driven around the comm to effect speed change. Commonly known as Schrage motors. If its a three phase motor just change two phases as you would a normal induction motor. Beware if it has an electrically driven pony motor to drive the brush gear you may have to seperate the supply to the pony motor to prevent that from reversing as well.

#129052 - 07/12/04 10:49 AM Re: * * * AC commutator motors* * *  
khansami  Offline
Junior Member
Joined: Jul 2004
Posts: 2
AC commutator motor we called it universal motor as it can run on both voltages AC & DC.
In case of DC voltage U can change direction of motor by revrsing supply connection,But in case of AC voltage U can not change direction because AC voltage alternates its voltage and current so reversal of current can not be achive in armature and field.

[This message has been edited by khansami (edited 07-29-2004).]

#129053 - 07/12/04 05:37 PM Re: * * * AC commutator motors* * *  
pauluk  Offline
Joined: Aug 2001
Posts: 7,520
Norfolk, England
But you can change the direction of rotation of an AC-fed universal motor if you go inside and reverse just the armature connections.

Member Spotlight
Sebago, ME, USA
Posts: 109
Joined: January 2005
Show All Member Profiles 

2017 NEC and Related
2017 NEC
Now Available!

Shout Box
Powered by UBB.threads™ PHP Forum Software 7.6.0
Page Time: 0.016s Queries: 14 (0.003s) Memory: 0.7652 MB (Peak: 0.9047 MB) Zlib enabled. Server Time: 2017-03-24 00:00:55 UTC