Siemens SIPROTEC 4 7UT6 Series Manual page 352

Mounting and Commissioning
3.2 Checking Connections
!
CAUTION
Be careful when operating the device on a battery charger without a battery
Non-observance of the following measure can lead to unusually high voltages and consequently, the
destruction of the device.
Do not operate the device on a battery charger without a connected battery. (Limit values can be
²
found in the technical data).
Connection examples for current transformer circuits are provided in the Appendix
Please observe the terminal assignments (see Appendix
Proceed as follows in order to check the system connections:
•
Protective switches for the power supply and the measured voltages must be switched off.
•
Check the continuity of all current and voltage transformer connections against the system and connec-
tion diagrams:
– Is the connection of all 3-phase current transformer sets to the device inputs correct and in accord-
ance with the set topology?
– Is the connection of all 1-phase current transformers to the device inputs correct and in accordance
with the set topology?
– Are the current transformers earthed properly?
– Are the polarities of the current transformers the same for each CT set?
– Phase assignment of all 3-phase current transformers correct?
– Are the polarities of all 1-phase current inputs correct (if used)?
– Are the voltage transformers earthed properly (if used)?
– Are the polarities of the voltage transformers correct (if used)?
– Is the phase relationship of the voltage transformers correct (if used)?
– Is the polarity for voltage input U
•
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).
352
B Terminal Assignments).
correct (if used, e.g. with open delta winding)?
4
C Connection Examples.
SIPROTEC 4, 7UT6x, Manual
C53000-G1176-C230-5, Edition 09.2016