ABB XT7, Руководство по эксплуатации и обслуживанию

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ABB | SACE Tmax XT
80 | © 2020 ABB | 1SDH001821A1002 - ECN000135670 Protections | 15 - Additional protections and functions
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Parameter Description Default
ZoneSelectivity
Activates/deactivates the function and selectivity time availability on
the display
(1)
NOTES :
• the function is only available with curve t = k
• if at least two of the selectivity G, Gext and MDGF are
enabled, the input and output are shared with the OR function; it
is sufficient that even a selectivity is activated to stimulate inputs
and outputs
OFF
Selectivity time
This is the trip time of the protection with the zone selectivity function
activated and selectivity input not present
(1)
The value is given in seconds and can be set within the range: 0.04 s
to 0.2 s, in 0.01 s steps
0,04 s
StartUp enable
Activates/deactivates the function and availability of the associated
parameters on the display
(2)
OFF
StartUp
Threshold
Protection threshold valid during Startup time, in the conditions in
which the function is activated
(2)
The value is given as both absolute value (Amperes) and relative value
(In) and can be set within the range: 0.2 In to 1 In, in 0.1 In steps
0,2 In
StartUp Time
This is the time for which the StartUp threshold remains activated and
is calculated from the moment the activation Threshold is exceeded
(2)
The value is given in seconds and can be set within the range: 0.1 s to
30 s, in 0.01 s steps
0.1 s
(1)
details on page 75
(2)
details on page78
Limitations and additional functions
• in the presence of curve t= k/I2, the protection trip time is forced to t41 if the calculation results give a
theoretical value lower than t41 itself
• Ekip Touch activates and displays Gext protection parameters if the presence of toroid S.G.R has been
enabled in the Settings menu (page 37);protection activation includes checking for the presence of toroide
S.G.R and signaling on the diagnosis bar in the event of alarm/absence
• the protection is automatically inhibited by the unit if absence of toroid S.G.R is detected
• the block functions and type of selectivity can also be accessed by means of the service connector (via
Ekip Connect) or communication via system bus (page 77)
• with CB in UL standard configuration, some parameters have different maximum values: I41 maximum =
1200A, Startup maximum = 1200A, t41 maximum = 400ms
MDGF Protection
MDGF
I41
t
t41
I
Function
MDGF protection protects against earth faults and detects the fault current with a dedicated toroid MDGF.
if MDGF toroid current exceeds threshold I41, the protection trips and, after a time established by the value
read and by the parameter settings, transmits the TRIP command.
To check and simulate the trip times in relation to all the parameters, please consult:
• summary table of the protections with the operating characteristics (page 87)
• the graph with trip curve (page 98)
Parameters
Toroid configuration is available in the Settings menu (page 37)
Parameter Description Default
External Toroid It allows the presence of toroid MDGF to be activated OFF
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