7PG2113/4/5/6 Commissioning & Maintenance
©2012 Siemens Protection Devices Limited
Chapter 6 Page 24 of 77
2.2.1 2 out of 3 logic
Ensure that at least 1 Phase Overcurrent element is set to Directional. Apply balanced nominal voltage. Apply
current at a level above the 50/51 setting on phase A only at the characteristic angle for forward operation,
normally 45º lagging. Ensure no Directional Phase Overcurrent element operation occurs. Note that non-
directional Phase Overcurrent and Non-direction Earth Fault elements may operate unless disabled.
Repeat the test with Phase A current as above but also with equal current in the B phase at 180º to that in the A
phase.
1 phase current
2 phase current
No 50/51-n Operation
50/51-n operation
Table 2.2-5
2 out of 3 Logic Test
2.3
Phase Overcurrent (67/50,67/51)
Figure 2.3-1 Phase Overcurrent
Voltage Inputs:
V
L1
(V
A
), V
L2
(V
B
), V
L3
(V
C
) for directional elements.
Current Inputs:
I
L1
(I
A
), I
L2
(I
B
), I
L3
(I
C
),
Disable:
51V, 51C, 46, 49, 50CBF, 79
Map Pickup LED:
51-n/50-n - Self Reset
Other protection functions may overlap with these functions during testing, it may be useful to disable some
functions to avoid ambiguity. It should be particularly noted that if the function is enabled, the 51C Cold Load
settings may modify the normal 50-n and 51-n settings if the CB is open during testing.
