ABB XT7, Руководство по эксплуатации и обслуживанию

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ABB | SACE Tmax XT
82 | © 2020 ABB | 1SDH001821A1002 - ECN000135670 Protections | 15 - Additional protections and functions
RC Protection
Rc
Idn
t
I
tdn
Function
Rc protection protects against the residual current earth faults by detecting the fault current with the
appropriate external Rc toroid.
The protection sends a TRIP command if the current from toroid Rc exceeds threshold Idn for longer than
Tdn.
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 97)
Parameters
Parameter Description Default
Threshold Idn
Defines the value that activates the protection; the value is given in
Amperes and can be set within a range of values from 3 A to 30 A
5 A
Time Tdn
This is the trip time of the protection; the value is given in seconds and
can be set within a range of values from 0.05 s to 0.8 s
0,06 s
Limitations and additional functions
Ekip Touch activates and displays the Rc protection parameters if the following conditions are observed:
• Rating Plug Rc model assembled and installed
•
Measurement
module assembled and installed
protection activation includes checking for the presence of toroid Rc and signaling on the diagnosis bar in
the event of alarm/absence