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3-Phase Motor Question

 

OK, cannot include a PHOTO of the connection diagram on the 3PH 3/4HP motor in question.? However it is rather a simple matrix diagram of nine points of connection:
o o o
o o o
o o o

They are labeled as follows:
LOW VOLT CONN
LINE-1-7 4
LINE-2-8 5
LINE-3-9 6
HIGH VOLT CONN
LINE-1 7-4
LINE-2 8-5
LINE-3 9-6
So, for the LOW VOLTAGE (208V) the CENTER connections are jumpered (/) to those ar LEFT and, for the HIGH VOLTAGE (480V) the CENTER connections.?

The label states "TO REVERSE DIRECTION INTERCHANGE ANY TWO LINE LEADS"

DO YOU KNOW if this means Connect LINE 1 to connector 2 and LINE 2 to connection 1 ?

Or connection LINE 1 to connector 8 and LINE 2 to connector 7 (LOW VOLTAGE CONN) and? connector 7 to 5 and connector 8 to 4 (HIGH VOLTAGE CONN)?

NOTE: I cannot see the motor itself, nor the connectors - just the label. I am wondering if the LINE connections from a THREE PHASE SOURCE are numbered One, Two, & Three respectively indicating the direction / sequence of the phases such that swapping LINE 1 with LINE 2 would actually reverse the motor's direction.





--
G.T.
wn4isx
 

It has been 50ish years since I studied 3 phase, however looking at my class notes, yes interchanging leads 1 to 2, 2 to 1 or? 1 to 3, 3 to 1? or 2 to 3, 3 to 2 will reverse the direction of rotation.
Youtube has loads of how to videos
Be careful, 3 phase can eat you alive, not only are all power leads hot to ground they are hot to each other!
?
There are very few regens from electrocution.
Regen refers to being restored to life in a video game.?
 

Ir I remember my 'Y' connection theory, to reverse the motor direction you would reverse any two input leads. Therefore if on 208 each phase line would be connected as such:

X---1
Y---2
Z---3
To reverse
Y--1
X--2
Z--3
or
X--1
Z---2
Y--3
or
Z--1
X--2
Y--3

If this was a Delta connection it would be 240 volts but the phase connections would be the same.
Phases are "usually" labeled X, Y, Z since you have no idea how the wiring is configured from thee supply transformer.

Dan Kahn

On Sunday, January 12, 2025 at 03:51:01 PM EST, Gooey via groups.io <gooeytarballs@...> wrote:


OK, cannot include a PHOTO of the connection diagram on the 3PH 3/4HP motor in question.? However it is rather a simple matrix diagram of nine points of connection:
o o o
o o o
o o o

They are labeled as follows:
LOW VOLT CONN
LINE-1-7 4
LINE-2-8 5
LINE-3-9 6
HIGH VOLT CONN
LINE-1 7-4
LINE-2 8-5
LINE-3 9-6
So, for the LOW VOLTAGE (208V) the CENTER connections are jumpered (/) to those ar LEFT and, for the HIGH VOLTAGE (480V) the CENTER connections.?

The label states "TO REVERSE DIRECTION INTERCHANGE ANY TWO LINE LEADS"

DO YOU KNOW if this means Connect LINE 1 to connector 2 and LINE 2 to connection 1 ?

Or connection LINE 1 to connector 8 and LINE 2 to connector 7 (LOW VOLTAGE CONN) and? connector 7 to 5 and connector 8 to 4 (HIGH VOLTAGE CONN)?

NOTE: I cannot see the motor itself, nor the connectors - just the label. I am wondering if the LINE connections from a THREE PHASE SOURCE are numbered One, Two, & Three respectively indicating the direction / sequence of the phases such that swapping LINE 1 with LINE 2 would actually reverse the motor's direction.





--
G.T.
 
Edited

Low voltage is a parallel star connection. This motor can¡¯t be connected delta. The phase windings are connected in series, only one star point (permanent inside the motor) for high voltage. Interchange any two supply lines to reverse rotation.?

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