FUNCTION CHARACTERISTICS
221
NVA100X-D - Manual - 02 - 2016
Internal selective block (Block4)
As well as to send or transmit a selective block toward other protective relays, each protective
element may be enabled for receive or transmit a selective block from/to other internal protective
elements.
[1]
The internal selective block of one or more element concerning the directional earth fault overcurrent
function may be enabled/disabled by means the
IEDC>BLK4
,
IEDC>>BLK4
,
IEDC>>>BLK4
and/or
IEDC>>>>BLK4
parameters (virtual input and output common to all protective thresh-
olds); the following operating modes are available:
IN - the element is enabled to receive the selective block from an internal input.
OUT - the element is enabled to send the selective block to an internal output.
OFF - the element is disabled to send/receive the internal selective block.
Transmission and reception for the same element is not allowed, so any stall situation due to wrong
setting is avoided.
The internal selective block can work together with an external selective block from other protective
relays (Block2).
Common confi gurations
The size of the residual current calculated vectorially on the measured currents on the sides of H
(
I
ECH
) or L (
I
ECL
), and the residual voltage between the value measured directly (
U
EC
) or the value
calculated from the three phase voltages vectorially (
U
EC
) can be selected.
Nota 1 The exhaustive treatment of the internal selective block (Block 4) function may be found in the “Internal selective block” paragraph inside
CONTROL AND MONITORING
section.
•
•
•
Common-F67NC.ai
Common configurations - 67N(Comp)
Common configurations
I
I ∙ c o s
3Votype67NC
IECtype67NC
U
E
U
EC
I
ECH
I
ECL
67N(Comp)
I
L1H
,
I
L2H
,
I
L3H
I
L1L
,
I
L2L
,
I
L3L
Mode67NC
3 V
o
Insens-Zone
O F F
O N
≥
M∙threshold
M
