Siemens siprotec 7SA522 User Manual

3.3 Commissioning
413
7SA522 Manual
C53000-G1176-C155-3
Switch off test current.
If start is possible without current flow:
• Starting by trip command of the external protection without current flow:
Binary input functions ´!%)6WDUWZR,µ and, if necessary, ´!%)UHOHDVHµ
(in or spontaneous or fault messages). Trip command (dependent on settings).
Busbar Tripping The most important thing is the check of the correct distribution of the trip commands
to the adjacent circuit breakers in case of breaker failure.
The adjacent circuit breakers are those of all feeders which must be tripped in order
to ensure interruption of the fault current should the local breaker fail. These are there-
fore the circuit breakers of all feeders which feed the busbar or busbar section to which
the feeder with the fault is connected.
A general detailed test guide cannot be specified, because the layout of the surround-
ing circuit breakers largely depends on the system topology.
In particular with multiple busbars the trip distribution logic for the surrounding circuit
breakers must be checked. Here check for every busbar section that all circuit break-
ers which are connected to the same busbar section as the feeder circuit breaker
under observation are tripped, and no other breakers.
Tripping of the
Remote End
If the trip command of the circuit breaker failure protection must also trip the circuit
breaker at the remote end of the feeder under observation, the transmission channel
for this remote trip must also be checked. This is done together with transmission of
other signals according to Sections “Testing of the Teleprotection Scheme with ...”
further below.
Termination of the
Checks
All temporary measures taken for testing must be undone, e.g. especially switching
states, interrupted trip commands, changes to setting values or individually switched
off protection functions.
3.3.7 Current, Voltage, and Phase Rotation Testing
≥ 10 % of Load
Current
The connections of the current and voltage transformers are tested using primary
quantities. Secondary load current of at least 10 % of the nominal current of the device
is necessary. The line is energized and will remain in this state during the measure-
ments.
With proper connections of the measuring circuits, none of the measured-values su-
pervision elements in the device should pick up. If an element detects a problem, the
causes which provoked it may be viewed in the Event Log.
If current or voltage summation errors occur, then check the matching factors (see
Section 2.1.3.1).
Messages from the symmetry monitoring could occur because there actually are
asymmetrical conditions in the network. If these asymmetrical conditions are normal
service conditions, the corresponding monitoring functions should be made less sen-
sitive (see Section 2.19.1.5) .
Quantities Currents and voltages can be viewed in the display field on the front of the device or
the operator interface via a PC. They can be compared to the actual measured values,
as primary and secondary quantities.

Siemens siprotec 7SA522 Specifications

General

Brand	Siemens
Model	siprotec 7SA522
Category	Protection Device
Language	English