W A T L O W Application Guide Electric Heaters

Typical 3-Phase Wiring Diagrams and Equations for Resistive Heaters Reference Data Definitions For Both Wye and Delta (Balanced Loads) V Continued Wye and Delta Equivalents

W

DELTA

= 3 W

WYE P

= Phase VoltageV W

ODELTA

=

�

W

DELTA L

= Line VoltageI W

OWYE

=

�

W

WYE P

= Phase CurrentI

L

= Line CurrentR= R

1

= R

2

= R

3

==Resistance of each branchW= Wattage

I

I R

V

R

V

R V

R V

R

I

I

Equations For Wye Only

Equations For Open Wye Only

(No Neutral)I I

=

I

V

=

V

/1.73W

=

I

=

V

/R = 3(V

)/RW V

=

V

/2W

= 1.73 V

I

=

/

(V

/R)W

=

2 (V

/R)

3-Phase Open DeltaRef. 83-Phase Delta (Balanced Load)Ref. 7 3-Phase Wye (Balanced Load)Ref. 53-Phase Open Wye (No Neutral)Ref. 6

I

I

I

R

R

R V

V

I

V

I

V

R

R

I

I

I

Equations For Delta Only Equations For Open Delta Only

I

= I

/1.73V V

= V

= V

I

= I

= I

W

= 3(V

)/RW I

= 1.73 I

= 1.73 V

I

W

= 2 (V

/R)

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