55
Matrix
Modules
HT relay
(Ir+Ly+Ib+In-If)*r
Id=If*r
If
2
If
1
F2
ACB
F1
mer
X
∆
- Y
REF Zone
CB
r
= ct ratio
Id
= deflection current
If1
= fault current @ F1
If2
= Fault current @ F2
Case 1.
EF inside the restricted zone (F1)
During EF within the zone, current flows back to Xmer star point through neutral sensing CT. The REF
module will give trip command to the breaker depending on pickup value.
Case 2.
EF outside the restricted zone (F2)
For EF outside the zone, fault current flows through phase CT & neutral CT in opposite direction
preventing the nuisance tripping from REF.
REF
Trip command
to HT Relay
Summary of Contents for OMEGA
Page 2: ...Stabilise systems with technology ...
Page 4: ...Change course quickly ...
Page 6: ...Match performance with prudence ...
Page 8: ...Adopt technological brilliance ...
Page 10: ...Keep an eye on upkeep ...
Page 26: ...Matrix Protection Control Units T UW M X4 5 ...
Page 70: ...Accessories ...
Page 84: ...Control Circuit Wiring ...
Page 92: ...Mounting Termination ...
Page 135: ...SP 50567 R5 ...