Siemens siprotec 7SA6 User Manual page 583

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7SA6 Manual
C53000-G1176-C133-1
Check the functions of all test switches that may be installed for the purposes of
secondary testing and isolation of the device. Of particular importance are test
switches in current transformer circuits. Be sure these switches short-circuit the
current transformers when they are in the test mode (open).
The short-circuit feature of the current circuits of the device are to be checked. An
ohmmeter or other test equipment for checking continuity is needed.
q
Remove the front panel of the device (see Figure 8-8 to 8-10).
q
Remove the ribbon cable connected to the I/O–2 board with the measured current
and measured voltage inputs (on the front side it is the right printed circuit board,
1
for housing size / , see Figure 8-8 [slot 19], for housing size
3
33], for housing size
printed circuit board so that there is no more contact anymore with the plug-in
terminal.
q
At the terminals of the device, check continuity for each pair of terminals that
receives current from the CTs.
q
Firmly re-insert the I/O–2 board. Carefully connect the ribbon cable. Do not bend
any connector pins! Do not use force!
q
Check continuity for each of the current terminal-pairs again.
q
Attach the front panel and tighten the screws.
Connect an ammeter in the supply circuit of the power supply. A range of about 2.5 A
to 5 A for the meter is appropriate.
Close the protective switches to apply voltage to the power supply. Check the polarity
and magnitude of the voltage at the device terminals.
The measured steady-state current should correspond to the quiescent power
consumption of the device. Transient movement of the ammeter merely indicates the
charging current of capacitors.
Remove the voltage from the power supply by opening the protective switches.
Disconnect the measuring equipment; restore the normal power supply connections.
Apply voltage to the power supply.
Close the protective switches for the voltage transformers.
Verify that the voltage phase rotation at the device terminals is correct. Note that the
device can be set for L1-L2-L3 rotation or L1-L3-L2 rotation under address 
3+$6( 6(4 in 36\VWHP 'DWD. See also Sub-section 6.1.1.
Open the protective switches for the voltage transformers and the power supply.
Check the trip circuits to the power system circuit breakers.
Check the close circuits to the power system circuit breakers.
Verify that the control wiring to and from other devices is correct.
Check the signalling connections.
Check the analog outputs (if available and used).
Close the protective switches to apply voltage to the power supply.
1
/ see Figure 8-10 [slot 33 right]. Furthermore, remove the
1
Installation and Commissioning
1
/ see Figure 8-9 [slot
2
8-39