4.29
Date Code 20080213 Instruction Manual SEL-351A Relay
Loss-of-Potential, Load Encroachment, and Directional Element Logic
Directional Control for Neutral-Ground and Residual-Ground Overcurrent Elements (Not in SEL-351A-1)
q From Figure 4.16; w Figure 3.18; e Figure 3.8.
Figure 4.18 Direction Forward/Reverse Logic for Neutral-Ground
Overcurrent Elements
Level
Direction
Settings
Directional
Control
32NF
q
DIR1 = F
DIR1 = N
Relay
Word
Bits
to Neutral Ground
Time-0vercurrent
Elements
w
to Neutral Ground
Instantaneous/
Definite-TIme
Overcurrent
Elements
e
ORDER = OFF
Setting
Forward
Forward
32NR
q
Reverse
Level 1
DIR1 = R
Reverse
DIR2 = F
DIR2 = N
Forward
Level 2
DIR2 = R
Reverse
DIR3 = F
DIR3 = N
Forward
Level 3
DIR3 = R
Reverse
DIR4 = F
DIR4 = N
Forward
Level 4
DIR4 = R
Reverse
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