Specifications

FTB 312-4 Revision 4 – 1-8-2008 5
Board Configuration
The 2903800 board is programmed from
the manufacturer for operation in the PC
312-4. The board will be clearly marked
in the area shown in Figure 1-2.
Options Switch
The options switch allows configuration of
the RS-485 address, number of markers
and alarm isolation.
Switch
Function
1 Alarm Isolation
(OFF – (default) Isolate)
(ON – Report Alarm)
2-4 RS-485 Address
5-7 Number of Markers
Alarm Isolation
Setting switch #1 to ON allows a red
alarm to be sent to other units over the
master/slave sync. This feature is used to
allow a slave beacon to send the rest of the
system into white backup when a failure
occurs in red night mode. The Master
beacon will read the alarm and send all
beacons into white backup. This is useful
for stack systems that have all beacons at
the same height and any failing beacon
should cause the system to go to white
backup. All units in the system must have
the switch set to ON for this feature to be
used. The default (OFF – Isolate) prevents
slave units from causing the system to go
to white back up if a red failure occurs on
the slave. Generally, a system should only
go to white back up if the top (master
beacon) fails in red night mode.
RS-485 Communication
RS-485 is used to communicate with the
FTM-5000 for monitoring of multiple
beacon systems as shown in Figure 2-10.
The connections are available on J8 in the
lower right corner. The pin assignments
are shown below:
When all switches are OFF, the RS-485 is
disabled. Once addressed, modem and
RS-232 communication will be disabled
and the RS-485 will become active.
Switches #2-4 define the address as
follows:
2
3
4
Address
OFF OFF OFF RS-485 Disabled
ON OFF OFF 1
OFF ON OFF 2
ON ON OFF 3
OFF OFF ON 4
Number of Markers
Switches #5-7 select the number of
markers installed. Once set, the unit will
alarm when the number of markers
detected falls below this level.
5
6
7
Markers
OFF OFF OFF 0
ON OFF OFF 1
OFF ON OFF 2
ON ON OFF 3
OFF OFF ON 4
ON OFF ON 5
OFF ON ON 6
ON ON ON 7