3 phase y connections

[HDbiker]

I own a machine shop, and a machine that I recently purchased has a motor that has a y connection and I cannot find any info as to how to wire it for low and high voltage. Could someone give me a little wiring diagram. Thanks I am desperate
HDbiker

 

[jbartos]

Suggestion: The safest approach is to contact the purchased machine tech support. They will guide you how to connect it or send you a wiring diagram.
Alternately and less safely, visit

http://www.mmsonline.com/articles/019904.html

http://www.reliance.com/prodserv/motgen/b7099.htm

http://www.usmotors.com/products/ProFacts/1-120-7.htm

etc. for more info

 

[draffy]

If it is Y connected (check the nameplate for the voltage you are using) then there will not be a low and high voltage connections - it can be connected only one way.

If the machine is belt/chain driven, remove the belt to test - if it runs backwards, it might damage the machine.
There could be 3 or 6 (two sets of 3) terminals.
If 6, one set of three will be connected by metal links.
Connect your cable to the other/free terminals, probably marked L1, L2 and L3.

Your cable is color coded - may be red, yellow, blue
Normally red (or first colour) is connected to terminal L1; yellow (or second colour) is connected to terminal L2; blue (or third colour) is connected to terminal L3.
This sequence is traditional - not absolutely neccessary. Any sequence will work - the worst that will happen is that the motor will run backwards. If it runs backwards, swap any two wires - usually second/L2 and third/L3 (only a convention)

Do a RAPID switch on and off - just to see which way the motor turns.

Replace the belt/chain.

Hope that helps.

 

[SteveKW]

ALL three phase motors have a high and low voltage capability. It's just the number of leads brought out for the customer that dictates how many ways he can connect it!

 

[aolalde]

Small and medium size motor are regularly built for dual voltage. If constructed under NEMA MG1 standards you will have nine terminals 1 to 9 for wye connection.

Higher Voltage connection:

Line 1 to Terminal 1, line 2 to terminal 2, line 3 to terminal 3

Connect and insulate T4 with T7
T5 with T8
T6 with T9

Lower Voltage connection:

Line 1 to T1 and T7
Line 2 to T2 and T8
Line 3 to T3 and T9

Connect together and insulate T4, T5and T6


The identification of the motor terminal leads could change for motors manufactured out of USA.

 

[jbartos]

Suggestion: Some motors come with a motor terminal board in a motor terminal box, consisting of six terminal posts accommodating the motor winding coils ends. There are standard jumpers that can connect the motor into delta or y, convertible in the field. These motors are single-speed, and standard system voltage (e.g. 380V three-phase) motors.