Download Print this page

ABB REL 352 Instruction Manual page 77

Numerical phase comparison transmission line protection system

Advertisement

Power Automation and Protection Division
7.3
Forward Zone 2 ground unit reach (Z2GF)
This setting is equivalent to the phase unit setting since it defines the forward reach of the Zone
2 ground unit in secondary ohms.
For Example:
Set Z2GF = 30 if the Zone 2 reach is 30 ohms at 75°.
7.4
Reverse Zone 2 ground unit reach (Z2GR)
Phase to ground units in REL 352 have been designed to have a definite reverse looking reach.
This makes the phase to ground units non-directional.
For Example:
If the reverse reach has been determined to be 15 ohms at 75°, set Z2GR = 15.
7.5
Zone 2 ground unit timer (T2G)
Selects the time delay for Zone 2 Ground fault detection in seconds. Set T2G = 0.15 if the min-
imum time delay for step distance coordination is 150 milliseconds.
7.6
Zone 3 phase unit reach (Z3P)
This setting controls the Zone 3 reach for phase to phase faults in secondary ohms. It is always
forward looking.
For Example:
If Z3 reach is 45 ohms at 75°, set Z3P = 45.
7.7
ZONE-3 PHASE TIMER (T3P)
Selects the time delay for Zone 3 Phase fault detection in seconds. Set T3P = 0.30 if the mini-
mum time delay for step distance coordination is 300 milliseconds.
7.8
Forward Zone 3 ground unit reach (Z3GF)
This setting is equivalent to the phase unit setting since it defines the forward reach of the Zone
3 ground unit in secondary ohms.
For Example:
Set Z3GF = 45 if the Zone 3 reach is 45 ohms at 75°.
7.9
Reverse Zone 3 ground unit reach (Z3GR)
Phase to ground units in REL 352 have been designed to have a definite reverse looking reach.
This makes the phase to ground units non-directional.
REL 352 Version 1.00
I.L. 40-201.9
5
5-9

Advertisement

loading