Manual MRG3 GB
Woodward
TD_MRG3_09.08_GB_Rev.New
49
5.6.6 Trip delay or time multiplier for earth fault element
(Similar to chapter 5.5.3).
Flashing of the LEDs IE + 1 + > + t> upon this setting.
Relay version MRG3-IER:
This version including directional feature allows different adjustment of the tripping time for forward
and backward faults. For this purpose, the display first shows the up to date tripping time for for-
ward faults. The LED that is marked by two arrows lights up in green. Thereafter, it is possible to
change this forward setting value via push-buttons <+><-> and store it by pressing >ENTER>. After
pressing the <SELECT> but-ton, the current setting value for backward faults is displayed. The
LED that is marked by two arrows lights up in red.
This backward setting value should be higher than the value set for forward faults to allow the pro-
tective de-vice to operate selectively at occurrence of forward faults.
When setting tripping times for forward faults and backward faults to the same value, the relay will
trip with the same time delay, i.e. without directional feature.
5.6.7 Reset mode for tripping characteristics in earth current path
(Similar to chapter 5.5.4).
Flashing of the LEDs IE + 1 + > + t> upon this setting
5.6.8 Pick-up value for earth faults resp. earth short circuit fast trips
(Similar to chapter 5.5.5).
Flashing of the LEDs IE + 2 + > upon this setting
5.6.9 Trip delay for earth fault s resp. earth short circuit fast trips
(Similar to chapter 5.5.6).
Flashing of the LEDs IE + 2 + > + t> upon this setting
5.6.10 COS/SIN-measurement
Depending on the neutral-point connection of the protected system the directional element for the
earth cur-rent path must be preset to cos
ϕ
(isolated mains) or sin
ϕ
(compensated mains) mea-
surement.
By pressing <SELECT> the display shows "COS" resp. "SIN". The desired measuring principle can
be selected by <+> or <-> and must be entered with password. Flashing of the LEDs IE + 1 + 2
upon this parameterisation.
