ABB | SACE Tmax XT
Protections | 5 - Power protections
61 | © 2019 ABB | 1SDH002039A1002 - ECN000093027 - Rev. A
D Protection
I7
t
t7fw
I
D
t7bw
Function
D protection is very similar to S protection, with the additional capability of recognizing the direction of the
current during a fault.
The current direction allows the user to find out whether the fault is on the supply side or load side of the
device controlled by Ekip Touch.
In ring type distribution systems, D protection allows the distribution section in which the fault has occurred
to be identified and disconnected without affecting the rest of the installation (using zone selectivity).
Depending on the direction of the fault, if the current of one or more phases exceeds threshold I7 (fw or bw)
for longer than time t7 (fw or bw), the protection activates and sends a TRIP command.
The
fault direction
is established by comparing the
detected fault current
with the
reference direction
.
NOTE:
the reference direction is calculated considering the set value of the power flow
direction and the phase sequence (cyclic direction of the phases):
Phase sequence (set) Power flow (set)
Phase sequence
(detected)
Reference direction
(forward direction)
123
High-->Low
123
High-->Low
123
Bottom --> Top
123
Bottom --> Top
123
High-->Low
321
Bottom --> Top
123
Bottom --> Top
321
High-->Low
321
High-->Low
123
Bottom --> Top
321
Bottom --> Top
123
High-->Low
321
High-->Low
321
High-->Low
321
Bottom --> Top
321
Bottom --> Top
To check and simulate the trip times in relation to all the parameters, please consult:
• the summary table of the protections with the calculation formulas (page 80)
• the graph with trip curve (page 92)
Parameter
Description
Default
Enable
Activates/deactivates the protection and its availability in the parameters
menu
OFF
Trip Enable
Activates/deactivates transmission of the open command: if disabled, the
alarm and exceedance of protection time are only managed as information
ON
Threshold I7 Fw
Establishes the value that activates the protection with forward direction.
The value is given as both absolute value (Amperes) and relative value (In)
and can be set within the range: 0.6 In to 10 In, in 0.1 In steps
4 In
Threshold i7
Bw
Establishes the value that activates the protection with backward direction.
The value is given as both absolute value (Amperes) and relative value (In)
and can be set within the range: 0.6 In to 10 In, in 0.1 In steps
4 In
Time t7 Fw
This is the trip time in the case of forward direction.
The value is given in seconds and can be set within the range: 0.1 s to 0.8
s, in 0.01 s steps
0,2 s
Time t7 Bw
This is the trip time in the case of backward direction.
The value is given in seconds and can be set within the range: 0.1 s to 0.8
s, in 0.01 s steps
0,2 s
ZoneSelectivity
(1)
Activates/deactivates the function and selectivity time availability on the
display.
NOTE
: configure selectivities S, S2 OFF to ensure that selectivity D
functions correctly and G
OFF
Selectivity time
Fw
(1)
This is the trip time of the protection with the zone selectivity function
activated, forward direction and selectivity input Fw not present.
The value is given in seconds and can be set within the range: 0.1 s to 0.8
s, in 0.01 s steps
0,13 s
Selectivity time
Bw
(1)
This is the trip time of the protection with the zone selectivity function
activated, backward direction and selectivity input Bw not present.
The value is given in seconds and can be set within the range: 0.1 s to 0.8
s, in 0.01 s steps
0,13 s
Continued on the next page
