ABB REL 356

ABB REL 356 Current Differential Protection
5-14
Testing
Volts
∠
Angle
I
Amps
∠
Angle
Fault Z
Ohms
∠
Angle
Relay System
Operation
AG at MTA 90% of reach fault
Va = 30
∠
0 Ia = 4.4
∠
-75 (285) 4.05
∠
75
Vb = 69
∠
-120 (240) Ib = 0
Vc = 69 ∠ -240 (120) Ic = 0
Z2T Trip
Fault type AG
Z2G Unit
Trip time 100-132 ms
AG at MTA –45˚ 90% of reach fault
Va = 30 ∠ 0 Ia = 4.4 ∠ -30 (330) 4.05 ∠ 30
Vb = 69
∠
-120 (240) Ib = 0
Vc = 69
∠
-240 (120) Ic = 0
Z2T Trip
Fault type BG
Z2G Unit
Trip time 100-132 ms
AG at MTA +45˚ 90% of reach fault
Va = 30
∠
0 Ia = 4.4
∠
-120 (240) 4.05
∠
120
Vb = 69
∠
-120 (240) Ib = 0
Vc = 69
∠
-240 (120) Ic = 0
Z2T Trip
Fault type CG
Z2G Unit
Trip time 100-132 ms
BG at MTA 90% of reach fault
Va = 69
∠
0 Ia = 0 4.05
∠
75
Vb = 30
∠
-120 (240) Ib = 4.4
∠
-195 (165)
Vc = 69
∠
-240 (120) Ic = 0
Z2T Trip
Fault type BG
Z2G Unit
Trip time 100-132 ms
BG at MTA –45˚ 90% of reach fault
Va = 69
∠
0 Ia = 0 4.05
∠
30
Vb = 30
∠
-120 (240) Ib = 4.4
∠
-150 (210)
Vc = 69 ∠ -240 (120) Ic = 0
Z2T Trip
Fault type BG
Z2G Unit
Trip time 100-132 ms
BG at MTA +45˚ 90% of reach fault
Va = 69
∠
0 Ia = 0 4.05
∠
120
Vb = 30 ∠ -120 (240) Ib = 4.4 ∠ -240 (120)
Vc = 69
∠
-240 (120) Ic = 0
Z2T Trip
Fault type BG
Z2G Unit
Trip time 100-132 ms
CG at MTA 90% of reach fault
Va = 69 ∠ 0 Ia = 0 4.05 ∠ 75
Vb = 69
∠
-120 (240) Ib = 0
Vc = 30
∠
-240 (120) Ic = 4.4
∠
-315 (45)
Z2T Trip
Fault type CG
Z2G Unit
Trip time 100-132 ms
CG at MTA –45˚90% of reach fault
Va = 69
∠
0 Ia = 0 4.05
∠
30
Vb = 69
∠
-120 (240) Ib = 0
Vc = 30
∠
-240 (120) Ic = 4.4
∠
-270 (90)
Z2T Trip
Fault type CG
Z2G Unit
Trip time 100-132 ms
CG at MTA +45˚90% of reach fault
Va = 69
∠
0 Ia = 0 4.05
∠
120
Vb = 69
∠
-120 (240) Ib = 0
Vc = 30 ∠ -240 (120) Ic = 4.4 ∠ 0
Z2T Trip
Fault type CG
Z2G Unit
Trip time 100-132 ms
The Zone 2 Ground unit (Z2G) should operate on all faults listed above. Trip time should be within
times shown.
Table 5-4. Zone 2 Phase-Ground Forward Internal Faults: Z2GF = 4.5 Ohms Z2GR = 4.5 Ohms