ABB Relion REB500, Руководство по применению

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Section 6
1MRK 505 353-UEN
BP-Additions to base documentation
50 Application Manual
Bay protection functions REB500
Step 7
Download the updated setfile to the central unit.
This requires that the PC running HMI500 be connected either directly to the cen-
tral unit or a bay unit, which is already operational.
WARNING: On no account connect the optical fiber link to the
new bay unit before the setfile has been successfully downloaded to
the central unit.
Step 8
• Switch off the bay unit
• Connect the optical fiber cable going to the central unit
• Switch on the bay unit
Step 9
Perform the busbar protection through-fault stability check (Refer to REB500
Commissioning Manual Sections “Checking protection stability”)
Step 10
Check the direction of the distance protection function with load current. This is
achieved by measuring real and apparent power in L1 phase.
The real and apparent power measurements of all the directional functions can be
viewed by selecting the HMI500 menu “
View/BP function monitoring ”. The di-
rection “ Forwards ” or “ Backwards ” is also displayed for both real and apparent
power as soon as a valid measurement has been made.
The display is influenced by the setting ‘CT Neutral’ “ Line side/Busbar side ” for
the distance protection function. The default setting of ‘CT Neutral’ for the dis-
tance protection function is CTs grounded on the busbar side.
Note the following with respect to busbar protection:
The side on which the CTs are grounded is of no consequence for the busbar pro-
tection and does not therefore have a setting. What is important, however, is that
the grounding of all the CTs on the busbars is the same (and have the same winding
sense), otherwise the differential current will not be correct.
Where this is not the case, the connections to the corresponding CT inputs on the
respective bay units must be reversed (current phase-angle rotated by 180°).
In the feeders in which the current direction has been rotated in the bay unit by
180°, the setting parameter 'CT Neutral' of the distance function must also be re-
spectively corrected to correspond to actual earthing direction of the CT.