Checking The System Connections - Siemens SIPROTEC 7SD80 Manual

Mounting and Commissioning
3.2 Checking Connections
3.2.3

Checking the System Connections

WARNING!
Warning of dangerous voltages
Non-observance of the following measures can result in death, personal injury or substantial property damage.
Therefore, only qualified people who are familiar with and adhere to the safety procedures and precautionary
measures should perform the inspection steps.
Caution!
Take care when operating the device without a battery on a battery charger.
Non-observance of the following measures can lead to unusually high voltages and consequently, the destruc-
tion of the device.
Do not operate the device on a battery charger without a connected battery. (For limit values see also Technical
Data, Section 4.1).
Before the device is energized for the first time, it should be in the final operating environment for at least 2
hours to equalize the temperature, to minimize humidity and to avoid condensation. Connections are checked
with the device at its final location. The plant must first be switched off and grounded.
Proceed as follows in order to check the system connections:
• Protective switches for the power supply and the measured voltages must be opened.
• Check the continuity of all current and voltage transformer connections against the system and connection
diagrams:
– Are the current transformers grounded properly?
– Are the polarities of the current transformer connections the same?
– Is the phase relationship of the current transformers correct?
– Are the voltage transformers grounded properly?
– Are the polarities of the voltage transformers correct?
– Is the phase relationship of the voltage transformer connections correct?
– Is the polarity for current input I
• Check the functions of all test switches that are 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.
• 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.
• Switch on m.c.b. for auxiliary voltage (supply protection), check the voltage level and, if applicable, the po-
larity of the voltage at the device terminals or at the connection modules.
• The current input should correspond to the power input in neutral position of the device. The measured
steady state current should be insignificant. Transient movement of the ammeter merely indicates the charg-
ing current of capacitors.
• Remove the voltage from the power supply by opening the protective switches.
• Disconnect the measuring test 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.
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correct (if used)?
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SIPROTEC, 7SD80, Manual
E50417-G1140-C474-A1, Release date 09.2011