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Terminal Markings and Connections
Three-Phase Motors-Single Speed

NEMA Nomenclature – 6 Leads

Single Voltage
External WYE Connection

L1

L2

L3

Join

1

2

3

4 & 5 & 6

Single Voltage External WYE Connection

 Single Voltage
External DELTA Connection

L1

L2

L3

1, 6

2, 4

3, 5

Single Voltage External DELTA Connection

 

Single and Dual Voltage
WYE-DELTA Connections

Single and Dual Voltage WYE-DELTA Connections

Single Voltage

Operating Mode

Connection

L1

L2

L3

Join

Start

WYE

1

2

3

4 & 5 & 6

Run

DELTA

1, 6

2, 4

3, 5

– – –

 

Dual Voltage*

Voltage

Connection

L1

L2

L3

Join

High

WYE

1

2

3

4 & 5 & 6

Low

DELTA

1, 6

2, 4

3, 5

– – –

*Voltage Ratio: 1.732 to 1.

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Terminal Markings and Connections
Three-Phase Motors-Single Speed

NEMA Nomenclature – 9 Leads

Dual Voltage WYE-Connected

Dual Voltage
WYE-Connected

Voltage

L1

L2

L3

Join

High

1

2

3

4 & 7, 5 & 8, 6 & 9

Low

1, 7

2, 8

3, 9

4 & 5 & 6

 

Dual Voltage DELTA-Connected

Dual Voltage
DELTA-Connected

Voltage

L1

L2

L3

Join

High

1

2

3

4 & 7, 5 & 8, 6 & 9

Low

1, 6,

2,

3,

– – –

 

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Terminal Markings and Connections
Three-Phase Motors-Single Speed

NEMA Nomenclature – 12 Leads

Dual Voltage External WYE-Connection

Dual Voltage
External WYE Connection

Voltage

L1

L2

L3

Join

High

1

2

3

4 & 7, 5 & 8, 6 & 9, 10 & 11 & 12

Low

1, 7

2, 8

3, 9

4 & 5 & 6, 10 & 11 & 12

 

Dual Voltage WYE-Connected Start DELTA-Connected Run

Dual Voltage
WYE-Connected Start
DELTA-Connected Run

Voltage

Conn.

L1

L2

L3

Join

High

WYE

1

2

3

4 & 7, 5 & 8, 6 & 9, 10 & 11 & 12

DELTA

1, 12

2, 10

3, 11

4 & 7, 5 & 8, 6 & 9

Low

WYE

1, 7

2, 8

3, 9

4 & 5 & 6, 10 & 11 & 12

DELTA

1, 6, 7, 12

2, 4, 8, 10

3, 5, 9, 11

– – –

 

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Terminal Markings and Connections
Three-Phase Motors-Single Speed

IEC Nomenclature – 6 and 12 Leads

Single and Dual Voltage
WYE-DELTA Connections

Single and Dual Voltage WYE-DELTA Connections

Single Voltage

Operating Mode

Connection

L1

L2

L3

Join

Start

WYE

U1

V1

W1

U2 & V2 & W2

Run

DELTA

U1, W2

V1, U2

W1, V2

– – –

 

Dual Voltage*

Voltage

Connection

L1

L2

L3

Join

High

WYE

U1

V1

W1

U2 & V2 & W2

Low

DELTA

U1, W2

V1, U2

W1, V2

– – –

 

*Voltage Ratio: 1.732 to 1.

Dual Voltage WYE-Connected Start DELTA-Connected Run

Dual Voltage
WYE-Connected Start
DELTA-Connected Run

Voltage

Conn.

L1

L2

L3

Join

High

WYE

U1

V1

W1

U2 & U5, V2 & V5, W2 & W5, U6 & V6 & W6

DELTA

U1, W6

V1, U6

W1, V6

U2 & U5, V2 & V5, W2 & W5

Low

WYE

U1, U5

V1, V5

W1, W5

U2 & V2 & W2, U6 & V6 & W6

DELTA

U1, U5, W2, W6

V1, V5, U2, U6

W1, W5, V2, V6

– – –

 

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