ABB SACE Emax 2 Series Operating Instructions Manual page 66

IU Protection
t
I6
t6
Neutral Protection Function
63 | © 2023 ABB | 1SDH001330R1002 - ECN000297030
Function
The protection trips if the current readings are unbalanced; the protection sends a TRIP command if the
detected unbalance exceeds threshold I6 for longer than t6.
IU
The protection is automatically self-excluding in two cases:
• the measurement of at least one current exceeds 6 In
• the maximum current value between all the phases is less than 0.25 In (in I Avg configuration) or
0.3 In (in I Max configuration)
To check and simulate the trip times in relation to all the parameters, please consult:
I
• summary table of the protections with the operating characteristics (page 95)
• the graph with trip curve (page 105)
Parameters
Parameter Description
Activates/deactivates the protection and its availability in the
Enable
parameters menu
Activates/deactivates transmission of the open command: if disabled,
Trip Enable
the alarm and exceedance of protection time are only managed as
information
Allows the unbalance calculation mode to be selected:
• With respect to I
• With respect to: I
Algorithm
Establishes the unbalance value that trips the protection.
Threshold I6 Unbalance is given in percentage value within the range: 2% to 90% with
1% steps.
This is the trip time of the protection; the value is given in seconds and
Time t6
can be set within a range: 0.5 s to 60 s, in 0.5 s steps
Neutral protection characterizes protections L, S and I differently on the neutral phase by introducing a
different control factor from the other phases.
The protection is available with the 4P and 3P + N configuration; the configuration parameters can be
accessed via the Settings menu (page 49).
Parameters
Parameter Description
Enable Activates/deactivates the protection
Defines the multiplicative factor applied to the trip thresholds and
curves of the protections for the current read on phase Ne:
Neutral
threshold
Limitations and additional functions
Ekip Touch rejects modification of thresholds I1 and InN in the absence of the following limitation: (I1 x
InN) ≤ Iu
• I1 is the threshold of L protection in amperes (example: In= 400 A and I1= 0.6 becomes I1= 240 A)I1
is the threshold of L protection in amperes (example: In= 800 A and I1= 0.6 becomes I1= 480 A)
• InN is the neutral threshold expressed as multiplicative factor (example: InN= 200% becomes InN= 2)
• Iu is the size of the CB
WARNING! With 150% and 200% threshold; if the measured neutral current exceeds 16In,
the Trip unit resets the protection to 100% by itself
: % Sbil = 100 x (I
max
: % Sbil = 100 x (max I
Avg
NOTE:max I
: maximum deviation among the measured currents,
Avg
calculated by comparing each current with the mean value;
I : mean value of the current readings
Avg
• 50 %: lowest trip thresholds for the neutral current
• 100 %: same trip thresholds for all phases
• 150 %: highest trip thresholds for the neutral current
• 200 %: highest trip thresholds for the neutral current
- I ) / I
max min max
) / I
Avg Avg
Ekip Touch - Protections
2 - Standard Protections
ABB | SACE Emax 2
Default
OFF
OFF
With
respect
to I
max
50 %
5 s
Default
OFF
50 %