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CHAPTER 6: ACTUAL VALUES
469 MOTOR MANAGEMENT RELAY – INSTRUCTION MANUAL
FIGURE 6–1: Vector display in EnerVista 469 Setup
IEEE conventions define vectors in terms of relative angles as shown below:
PER IEEE CONVENTIONS
Source
PARAMETERS AS SEEN
G
BY THE 469 RELAY
Voltage
WATTS = Positive
VARS = Positive
PF = Lag
Current
469 Relay
M
Load
FIGURE 6–2: Flow Direction of Signed Values for Watts and Vars
All phasors calculated by 469 relays are rotating phasors that maintain the correct phase
angle relationships with each other at all times.
For display purposes, all phasor angles in a given relay are referred to phase Van or Vab,
depending on the
S2 SYSTEM SETUP
If set to "Wye", the reference quantity is Van; if set to "Open Delta", the reference quantity is
Vab. If neither voltage is available, the relay uses the current in Phase A as reference.
The phase angles are assigned and displayed as positive angles. However, by design, the
relay will always work with angles in the lagging direction. This is illustrated below.
Phase Rotation
Ic
Vcn
Vca
Vbn
Ib
Vbc
VOLTAGE SENSING
VT CONNECTION TYPE
Vab
Van
Ia
806558A1.CDR
settings.
6–17
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