Siemens Reyrolle 7SR45 Argus Device Manual page 51

This setting is used to allow the element to be switched on and off if it is not required. A separate setting is
provided for each element. This setting can be used to select the number of elements required.
Parameter State
Disabled
Enabled
Gn 50N-n Setting
Default setting: 1.0 ⋅ I
This setting defines the operating current threshold of the element. The applied current must exceed this
setting by a factor of 1.00x for pickup of the element. The operation timing then depends on the selected
delay for the element setting. The element pickup resets when the current is reduced under the following
conditions:
•
0.2 ⋅ I to 0.9 ⋅ I
rated
•
1.0 ⋅ I to 20.0 ⋅ I
rated
This setting should be set to suit the individual application
Gn 50N-n Delay
Default setting: 0.00 s
This setting is set to suit the individual application.
Gn 50N-n Inrush Action
Default setting: Off
High levels of inrush currents into reactive components, for example transformers; when they are switched in
can result in operation of overcurrent elements. The inrush current can be detected by a high percentage of
2nd harmonic current content by the 81HBL2 element. This parameter can be configured to inhibit the over-
current element automatically.
Parameter Value
Off
Inhibit
Settings Example
There should be little or no current flowing to earth in a healthy system. So earth fault relays can be given far
lower pickup levels than relays which detect excess current above load current in each phase conductor. Earth
fault relays are important where the fault path to earth is a high-resistance one (such as in highly arid areas) or
where the system uses high values of earthing resistor/reactance as any earth fault current that flows in the
phase conductors is limited.
Settings Menu
CONFIGURATION > FUNCTION CONFIG
Parameter
Gn Derived E/F
CONFIGURATION > CURRENT PROT'N > DERIVED E/F > 50N-n
Parameter
Gn 50N-n Element
Reyrolle, 7SR45, Device Manual
C53000-G7040-C101-2, Edition 09.2020
Description
The element is inactive.
The element is active.
rated
is ≥ 90 % I
rated op
is ≥ 94 % I
rated op
Description
The earth fault element is not inhibited by operation of the 81HBL2
element.
The earth fault element is inhibited by operation of the 81HBL2 element
and automatically released when the 81HBL2 element resets.
Setting Options
Disabled
Enabled
Setting Options
Disabled
Enabled
3.4 Instantaneous Derived Earth Fault Protection (50N)
Settings
Default Gn1
Disabled –
Settings
Default Gn1
Disabled –
Functions
Gn2
–
Gn2
–
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