ERL F-PRO 116, User Manual

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5-6 F-PRO 116 User Manual D05125R01.20
Measured Neutral current is processed after filtering; if the current measured is greater than the
set current then this function will go for the operation after the set delay (51G) or as per the set
Inverse curve (51G) or instantaneous (50G). The function is provided with the additional feature
of
“ Inrush Blocking ” . This is provided to block the function from operation when second harmonic
current is present along with the fundamental (when used in transformers application).
Each stage (50G-1, 50G-2 & 51G) can be independently inhibited via external input status which
can be configured from input matrix, in case blocking of any stage is required depending on
application needs.
The Metering menu is provided in the front LCD display and it provides additional information for
the user as it displays the value of neutral current magnitude and angle.
50G - Neutral Overcurrent Logic diagram
Figure 5.5: Logic Diagram of 50G Function
Table 5.6: 50G Neutral Overcurrent Settings (No. of Stages – 2)
Setting Description Range
Function Activation Enable/disable
Pickup
0.05 to 25 A (1 A) / 0.25 to 125 A (5 A)
Pickup Delay 0.00 to 999.99 seconds
Inrush Blocking Enable/disable
51G
– IDMTL Neutral Overcurrent Logic diagram
Figure 5.6: Logic Diagram of 51G Function
Functional Block Via External
Input
Pickup
Timer
Functional Block Via External Input
Function Enable
IG > 50G Pickup
Inrush Block
50 G Operated
Function Enable
IG > 51G Pick up
Inrush Block
51G Operated