IG-267-EN versión 01; 07/04/2017
29
General Instructions
ekor
.rpa
Protection functions
4.5. Broken conductor unit
The
ekor
.rpa-100 model 120 systems are fitted with the
broken conductor unit (46BC).
Conventional protection functions cannot detect conditions
in which one of the conductors is broken.
The broken conductor unit (46
Broken Conductor
) can
be used to detect broken conductors, by monitoring
the sequence currents, and another series of conditions
detailed in this section.
4.5.1. Calculation of sequence currents
The broken conductor unit is supplied by the sequence
currents (I
1
, I
2
and I
o
) previously calculated by the system.
The sequence current calculation is carried out in
accordance with these formulae:
Where,
With the phase A sequence components known, the B
and C sequence components will be identical in modules,
displaced 120° in angle in the case of direct and inverse
sequence, and with the same angle in the case of zero-
sequence.
Summary of Contents for ekor.rpa Series
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