5
Although most of the expected applications for the BFD use a single BFD and
a G3, the design allows some flexibility for those applications where more than
one BFD is required.
Up to 7 BFDs maybe connected to a single serial port, each one identified by
a unique address in the range 0..6. The address is set by DIP switch positions 1,
2 & 3, eg, to set BFD address to 6, set 1 and 2 ON, and 3 OFF. Note that each
of the 32 display boards in the BFD will have to have these DIP switches set for
the same unit address. Power must be cycled OFF, then ON so that the new DIP
switch values will take effect.
The remote display primitive describes a region of the current Display page
to be rendered on a BFD. The configuration of each “remote display primitive”
includes the logical serial port that the BFD is connected to, and the unit address
of the BFD as set by it's DIP switches. By placing more than one “remote
display primitive” on the G3’s Display Page, each BFD can be made to display
different information.
A BFD may show the same information as another BFD on the same serial
port by simply setting the unit addresses the same on both units. To show the
same information on BFDs on different serial ports, simply overlay the remote
display primitives on the current Display page and configure the logical port and
BFD address as appropriate.
The display information from the G3 must be passed to each BFD. The
easiest way to do this is to wire to the unused RS485 connector in the first BFD
(See Figure 3a) and connect it to the second unit (daisy chain wiring). Power for
each unit can be wired as normal.
USING MULTIPLE BFDS WITH A SINGLE G3
MULTIPLE BFDs DISPLAY THE SAME INFORMATION
REPLACING A DISPLAY BOARD
The display boards are held in place by a display frame assembly, which is
built from nine aluminum display rail extrusions. The extrusions have a slot on
each side to receive the PC board edge of the display boards. The boards simply
slide into place. A male right angle connector on the top side of the board mates
with a female connector of the board above it, thus, passing the power and signal
from the top board to the bottom board. In normal operation, the display frame
is fastened to the enclosure using 4 nuts (Figure 8a). However, these nuts can be
removed to service the display, if required. The display frame has a pivot point
along the bottom edge, which allows the top edge of the frame to tilt outside the
enclosure, providing access to the top display boards. Display boards are easily
removed by disconnecting the appropriate wiring connection from the top board
(Figure 7b), separating the boards and sliding them out the top of the frame
assembly (Figure 8).
Each display board has a 8 circuit dip switch which is used to set its location
address. This address is determined by the board’s physical location within the
BFD display (Figure 7a).
1. Turn off AC mains power to the BFD at the circuit breaker.
2. Remove the rear cover of the BFD. Do Not Remove The Front Window To
Attempt To Gain Access To The Inside Of The BFD.
3. Remove the AC mains 3 position removable terminal block (Figure 3c).
Disconnect the main wiring harness connector (Figure 10a) from the power
supply. Disconnect the fan cable assembly (Figure 5a) or the NEMA 4 cooler
cable assembly (Figure 6b). Disconnect the RS485 cable to the G3 (Figure
3a).
4. Remove the 6 #8 kep nuts which fasten the power supply subassembly to the
enclosure. Remove the power supply subassembly (Figure 8b).
5. Remove the NEMA 4 Cooling kit (if applicable - See “Instructions for
installing the optional NEMA 4 cooling kit”).
6. Remove the 4 #8 kep nuts which fasten the display frame assembly to the
front of the enclosure (See Figure 8a). The display frame assembly will now
tilt back to allow access to the display boards.
7. Lift off the display frame top stop bracket (See Figure 8).
8. Locate the column of display boards with the faulty display board and remove
the two wiring cables (which connect the main wiring harness to the top
display board, Figure 7b).
9. Remove the appropriate board (See Figure 8). Note the DIP switch setting
(Figure 7a) on the old board.
10. Change the DIP switch setting on the replacement board and install the new
board in the same position as the old board. Make sure that the board-to-board
pins are properly aligned.
11. Re-connect the two wiring bundles observing the proper orientation of the
connectors (Figure 7b).
12. Repeat steps 1 through 7 in reverse order.
13. Note that if the DIP switch setting on a board must be changed (due to
incorrect setting), the power to the unit must be cycled in order for the change
to take effect.
TROUBLESHOOTING
FIGURE 7
