Parameter: 55-n UC Guard
•
Default setting: Enabled
This can be used to block element operation if the current is below the setting in all 3 phases (?). This is
used to avoid nuisance operations at very low levels of current.
Parameter: UC Guard Setting
•
Default setting: 0.2 x I
n
(0.2 â‹… I
rated
)
This defines the minimum current required for the element to operate. This should be set to a level below
which the power factor should not be considered as significant or cannot be measured accurately.
Parameter: VTS Inhibit
•
Default setting: No
The 55-n element can be set to be automatically inhibited when a voltage has been identified as invalid
by the VTS element.
Settings Example
An output is required when any phase load has a power factor below 0.8 lagging for more than 10 seconds.
[dw_7SR5_function55SettingsExample, 1, en_US]
Functions > Protection > 55
Element Enabled
Operation Under
1Ph/3Ph Power 1Ph
Dir. Control Lag
Setting 0.8
Delay 10 s
UC Guard Enabled
UC Guard Setting 0.1 â‹… I
rated
Protection and Automation Functions
5.21 55 Power Factor
298 Reyrolle 7SR5, Overcurrent Protection Device, Device Manual
C53000-G7040-C014-1, Edition 11.2019
To Next Page
Loading...
