Siemens 7SR242 Duobias - Phase Overcurrent (50, 51); Figure 2-3 Phase Overcurrent

7SR242 Duobias Commissioning & Maintenance Guide
©2010 Siemens Protection Devices Limited Chapter 6 Page 18 of 57
2.1.3 Phase Overcurrent (50, 51)
Figure 2-3 Phase Overcurrent
Voltage Inputs: None
Current Inputs: W1-I
L1
(I
A
), W1-I
L2
(I
B
), W1-I
L3
(I
C
), or W2-I
L1
(I
A
), W2-I
L2
(I
B
), W2-I
L3
(I
C
),
Disable: 46, 49, 50BF, 87BD, 87HS
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.
These elements can be allocated to W1 or W2 current inputs by relay settings, ensure that current is injected on
the correct input.
Particular care should be taken when testing overcurrent functions that the thermal rating of the current inputs is
not exceeded.