Parameter Value Description
Disabled This element is switched out and is not available.
Enabled The element is available for use and can be parame-
terized.
Parameter: Measurement
•
Default setting: RMS
Selects whether fundamental frequency RMS or the True RMS value of the measured currents is used.
Parameter Value Description
RMS Select this if it is required to consider the effects of
harmonic currents. This method may be required if
there are significant harmonic content such as at
capacitor banks or filter networks. This method is
required for correct grading with fuses or electrome-
chanical overcurrent relays.
Fundamental This method is used:
•
When harmonic components are not to be
considered in the current evaluation.
•
For current/time grading with devices which also
measure fundamental current.
•
For unbalance type protection where the unbal-
ance applies at fundamental frequency and the
risk of errors in transient response measurement
can be avoided.
Parameter: Dir. Control
•
Default setting: Non-Dir
This setting is used to define whether the element will operate for overcurrent detection in the Forward
or Reverse direction based on the 67 directional element decision or for any overcurrent regardless of
the 67 direction. This allows the overcurrent protection to have different current and time settings for
forward and reverse faults by using 2 elements. Additional non-directional elements can be used for
backup or high set and will still be active if the main directional elements are inhibited by VTS etc.
This parameter is not provided in devices that do not have voltage inputs or for current inputs that are
not polarized by the voltage inputs.
Parameter Value
Description
Non-Dir The element operates regardless of the current direc-
tion or presence of voltage.
Forward The element will operate only for current in a forward
direction.
Reverse The element will operate only for current in a reverse
direction.
Parameter: Setting
•
Default setting: 1 x I
n
(1 ⋅ I
rated
)
This setting defines the operating current threshold of the element.
This setting should be chosen to suit the individual application.
Protection and Automation Functions
5.11 50 Instantaneous Overcurrent – Phase
Reyrolle 7SR5, Overcurrent Protection Device, Device Manual 209
C53000-G7040-C014-1, Edition 11.2019
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