Siemens SIPROTEC 7VU681 User Manual page 82

Mounting And Commissioning
3.2 Checking Connection
• Check of the cubicle and the devices for damage;
• Check of earthing of the cabinet and the device;
• Check the external cabling for condition and completeness.
Acquisition of Technical Power System Data
For checking protection parameterization (allocation and settings) in accordance with power system require-
ments, recording of technical data of the individual components is necessary in the primary system. This in-
cludes,the voltage and current transformers.
Where deviations from the planning data are found, the settings of the protection must be modified accordingly.
Analog Inputs
The check of the current and voltage transformer circuits includes:
• Acquisition of technical data
• Visual check of transformers, e.g. for damage, assembly position, connections
• Check of transformer earthing, especially earthing of the broken delta winding in only one phase
• Check cabling in accordance with circuit diagram
• Check of the short circuiters of the plug connectors for current circuits
Further tests are under certain circumstances necessary in accordance with contract:
• Insulation measurement of cable
• Measurement of transformation ratio and polarity
• Burden measurement
• Checking the functions of test switches, if used for secondary testing.
• Measuring transducers/ Measuring transducer connection
Binary Inputs and Outputs
For more information see also Section 3.3.
• Setting of binary inputs:
- Check and match jumper allocation for pickup thresholds (see Section 3.1)
- Check the pickup threshold - if possible - with a variable DC voltage source
• Check the tripping circuits from the command relays and the tripping lines down to the various components
(circuit breakers, excitation circuit, emergency tripping, switchover devices etc.)
• Check the signal processing from the signal relays and the signal lines down to the station control and
protection system; to do so, energize the signal contacts of the protective device and check the texts in the
station control and protection system
• Check the control circuits from the output relays and the control lines down to the circuit breakers and
disconnectors etc.
• Check the binary input signals from the signal lines down to the protective device by activating the external
contacts.
Voltage Trans-former Miniature Circuit Breaker (VT mcb)
Since it is very important for the undervoltage protection, that this functions are blocked automatically if the
circuit breaker for the voltage transformers has tripped, the blocking should be checked along with the voltage
circuits. Switch off voltage transformer protection switches.
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SIPROTEC, 7VU681, User Manual
C53000-G1176-C368-1, Release Date 07.2012