ABB XT7, Руководство по эксплуатации и обслуживанию

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ABB | SACE Tmax XT
Protections | 9 - Voltage Advanced protections 59 | © 2020 ABB | 1SDH001821A1002 - ECN000135670
RV Protection
U22
t
t22
V
RV
Function
The protection trips if loss of insulation occurs (verification of residual voltage U0); the protection sends a
TRIP command if voltage U0 exceeds threshold U22 for longer than t2.
The protection is always available in the 4P configuration; if presence of neutral voltage is activated in
Measurement module (page 137). protection is also available for 3P and 3P + N configurations.
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 88)
• the graph with trip curve (page 101)
Parameters
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
OFF
Threshold U22
Establishes the value that activates the protection.
The value is given as both absolute value (Volts) and relative value (Un)
and can be set within the range: 0.05 Un to 0.5 Un in 0.001 Un steps
0,15 Un
Time t22
This is the trip time of the protection; the value is given in seconds and
can be set within a range: 0.05 s to 120 s, in 0.01 s steps
15 s
Reset Time
This is the time the alarm is retained after the protection has quit the
alarm condition; it can be useful for keeping the timing activated when
the protection is temporarily deactivated.
The value is given in seconds and can be set within the range: 0 s to
0.2 s, in 0.02 s steps
0 s
Limitations and additional functions
The block functions can also be accessed by means of the service connector (via Ekip Connect) or by
connection to the system bus (page 78).