8-2
ALPS Advanced Line Protection System
GE Power Management
8.1 INTRODUCTION
8 LOCAL USER INTERFACE
8
8.1.3 CONTROL KEYS
a) METERING/CLEAR KEY [CLR]
Depending on the current state of the display, the [CLR] key has the following uses: aborting a key sequence in progress,
clearing an error message, activate scrolling of metering; and display recorded trip data.
If the [CLR] key is pressed while entering data, all or part of the display will be blanked. If there is user-entered data on the
display, only the data will be blanked. For example, if the user is entering a Setting value or responding to an Action prompt
when the [CLR] key is pressed, only the user's input will be blanked. The name of the setting or the prompt will remain on
the display. If there is no user-entered data on the display when the [CLR] key is pressed, the entire display will be blanked
and the relay screen will be displayed.
When a keypad error message is displayed, press [CLR] to remove it (all other keys will be ignored). When the error mes-
sage is removed, the user will be returned to the current operation being performed.
Pressing the [CLR] key while a trip message is displayed will display the trip information. The target information (TRIP
mes-
sage) and date/time of the trip for each of the accumulated faults are displayed, starting from the most recent fault (that is,
the one whose TRIP message was on display before pressing the [CLR] key). The trip time resolution is one millisecond. A
typical trip information display is shown below.
If [CLR] is pressed again, the target information, trip time, and date for the next most recent fault is displayed. The user can
scroll through all the accumulated trip information using the [CLR] key. The most recent trip message will flash. Pressing
the [CLR] key after the last trip will display the relay screen. Scrolling through the trip information using the arrow keys is
not possible; thus the trip information may only be viewed from the most recent to the oldest when using the [CLR] key.
Pressing the [CLR] key when the screen is blank or when the relay screen is displayed causes Present Values/Metering to
be displayed. Each screen of values is displayed for 4 seconds before proceeding to the next screen. Screens containing
breaker health present values are not displayed. After automatically scrolling through all the screens, the display returns to
the relay screen. The items displayed are described later in Section 8.2.4: REQUEST PRESENT VALUES on page 8–18.
The user cannot use the arrow keys to scroll through the present values.
Both the fault data display and the Present Value display are stopped by one of the following: trip, fail/warn message, or a
key being pressed.
b) ARROW KEYS
The arrow keys are used to scroll through the lists of commands and categories and adjust the contrast of the LCD display.
By pressing the
↑
and
↓
keys, the user can select any item in the menu displayed. The display scrolls upward or downward
when there are more items than can be displayed on three lines.
When the user reaches the desired category, pressing the [ENT] key will then produce the name of the category on the top
line and the first three items in that category on the remaining three lines. The user can use
↑
or
↓
keys to scroll through
these items. The
↑
key scrolls in a reverse direction through a list of categories or items while the
↓
key scrolls forward
through a list. The
↑
key will select the item before it in a list (for example, from item 5 to item 4). The
↓
key will select the
item after it in a list (for example, from item 5 to item 6).
Both the
↑
and
↓
keys wrap. Wrapping occurs when the top or bottom of a list are reached. The last item becomes the first
and the first item becomes the last.
c) ENTER KEY [ENT]
The [ENT] key is used to enter data or to enter a choice. When a category name or command is selected on the display and
the [ENT] key is pressed, the user is choosing to scroll through that category. After the user selects an item with the [ENT]
key, the numeric keys and decimal point are used to enter the value. When the correct value has been entered, the [ENT]
key is used to accept the new value for the selected item.
#1
19:10:01.259
06/29/95
TRIP AB Z2 145.0MI
