Document No: LT0117
F4000 LCD Operator's Manual
Interpreting The Display
Issue 2.38
19 April 2002
Page 4-9
4.4.3 ZONE ISOLATED ("ISO") LED INDICATOR
An Amber indicator per zone that is interpreted as:
(a)
OFF The normal state; indicates that the zone is not isolated and that any alarm or
fault conditions detected on that zone will generate Brigade signals, bell
operation, and ancillary device operation as configured for that zone.
(b)
ON
Indicates that the zone is isolated. Alarm and fault conditions will still be
displayed but will not initiate any control or annunciation functions.
(c)
F
Indicates that the zone is in "AUTO-RESET" mode.
4.5 LED
PHASING
For FIPs with a large number of display boards, the power requirements can become
excessive if too many of the LEDs are on. To reduce the power requirements, the FIP is
able to "phase" the display boards.
The FIP calculates the number of LEDs on steady or flashing for all Display boards, but
excludes Relay Driver boards. If this number rises above 255, then phasing starts. If it then
falls below 249, phasing stops.
If phasing has started, then only 6 boards display their data at one time. All other LEDs on
Display boards are turned off. Every second, one board is turned off, and another is
enabled to turn on its LEDs. In this way, the 6 display board "window" is shifted around all of
the display boards. If phasing is not enabled, then all boards show their data.
TIME
BOARD NUMBER
1
2
3
4
5
6
7
8
1
X
X
X
X
X
X
2
X
X
X
X
X
X
3
X
X
X
X
X
X
4
X
X
X
X
X
X
5
X
X
X
X
X
X
6
X
X
X
X
X
7
X
X
X
X
X
X
8
X
X
X
X
X
X
X = BOARD DISPLAYING DATA
FIG 4.1 PHASING OF DISPLAY BOARDS