ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
ShoutChat
Recent Posts
Increasing demand factors in residential
by gfretwell - 03/28/24 12:43 AM
Portable generator question
by Steve Miller - 03/19/24 08:50 PM
Do we need grounding?
by NORCAL - 03/19/24 05:11 PM
240V only in a home and NEC?
by dsk - 03/19/24 06:33 AM
Cordless Tools: The Obvious Question
by renosteinke - 03/14/24 08:05 PM
New in the Gallery:
This is a new one
This is a new one
by timmp, September 24
Few pics I found
Few pics I found
by timmp, August 15
Who's Online Now
0 members (), 260 guests, and 20 robots.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
Joined: Jul 2004
Posts: 1
N
nader Offline OP
Junior Member
Please can show me by drawing who can I change the diriction of the AC commutator motors.

Thanks allot.

Stay up to Code with the Latest NEC:


>> 2023 NEC & Related Reference & Exam Prep
2023 NEC & Related Reference & Study Guides

Pass Your Exam the FIRST TIME with the Latest NEC & Exam Prep

>> 2020 NEC & Related Reference & Study Guides
 

Joined: Aug 2001
Posts: 7,520
P
Member
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).]

Joined: May 2004
Posts: 186
A
Member
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.

Joined: Jul 2004
Posts: 2
K
Junior Member
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).]

Joined: Aug 2001
Posts: 7,520
P
Member
But you can change the direction of rotation of an AC-fed universal motor if you go inside and reverse just the armature connections.


Link Copied to Clipboard
Powered by UBB.threads™ PHP Forum Software 7.7.5