3 element power point from eric haut at pgn (portland, or)

1. Vectoring Basics
Start With a Zero
Reference Voltage.
 Wye – ENA
 Delta – EBA

2. Vectoring Basics
 Potential – Open Arrow.
 Current – Closed Arrow.
 Arrowhead Denotes Polarity.
 Current Enters the Polarity side of a Current Coil.
 Cannot have a C-Phase without first having A-Phase and B-Phase.
 The ONLY Current Coil that is ever reversed is B-Phase.
 B-Phase Current Coil Reverses when you Alter it.
Half Coils and ‘Z’ Coils are considered Altered.
 All Meter Elements Have Forward Torque at Unity Power
Factor.
Forward torque means less than 90 degrees between
the Potential coil and the current coil vectors.

3. Sequence for Vectoring
 Learn and Memorize the Three Basic System Vector Diagrams.
 Learn and Memorize Meter Footprints.
 The Meter Footprints show the Potential Connections and
Currents being measured. Labeling the connections is helpful.
 Apply the Rules Regarding Forward Torque and Which Current
Coils may be Reversed.
 Draw the Meter Vectors.
 Create a hypothetical load.
 Do the Math.

4. Three Element Meters
 Forms 16/15 & 9/8 (Conforming)

5. Form 9 and 16 vectors
 System Vectors.
 Meter Vectors.
Non-conforming meter.

6. Form 8/9 and 15/16 vectors
 System Vectors.
 Meter Vectors.
3-currents and 3-voltages.

7. Form 9s as a 3Ø 4-Wire Wye Meter

8. Form 16 as a 3Ø 4-Wire Wye Meter

9. Form 16 as a 3Ø 4-Wire Delta Meter

10. Create a Load
A 48 H.P. Motor with 36 kW of load
(For simplicity phases are evenly loaded and 1.0 pf)
36000 watts of 3-phase
36000 / (120 x 3) = 100 amps - Wye
36000 / (240 x √3) = 86.6 amps – Delta
Wye Potentials all = 120 Volts (as seen by the meter)
Delta Potentials are 120, 120 and 208 Volts (as seen by the meter)

11. Form 16 Vectors
Total watts = 36000
‘A’ Element watts =
120 x 100 x cos 0º
= 12000 watts
‘B’ Element watts =
120 x 100 x cos 0º
= 12000 watts
‘C’ Element watts =
120 x 100 x cos 0º
= 12000 watts
Total: = 36000 Watts

12. Form 15 / 16 Vectors
Total watts = 36000
‘A’ Element watts =
120 x 86.6 x cos 30º
= 9000 Watts
‘B’ Element watts =
120 x 86.6 x cos 30º
= 9000 Watts
‘C’ Element watts =
208 x 86.6 x cos 0º
= 18000 watts
Total: = 36000 Watts

13. Exercise

14. The End