CTI Products NCB/FL with Fiber Interface - Manual (Page 32)

CTI Products, Inc. NCB-EL/FL User Guide
Appendix D. Troubleshooting 29
Table D4
If the ETH RX LED (on
local NCB) . . .
REASON CORRECTIVE ACTION
Occasionally blinks on, then
off.
Normal operation indicating a message
packet has been detected on the IP
network.
Go to next Table.
Does not illuminate when
“RSVC” button on remote
NCB is pressed.
1. Ethernet port is not terminated correctly
to the IP network.
2. If Unicast/Replicated addressing mode is
being used, IP addresses for local and
remote NCB are not compatible.
3. If Multicast addressing mode is being
used, IP network routers or switches are
not configured properly.
1a. Verify that OPTION switch positions 7
and 8 are set correctly for the Ethernet
connector being used. See Step 6A in
Installation section.
b. Verify that the cable from NCB
Ethernet port is terminated correctly to
IP network. Check the ‘connection’
LED that is found near each port on
most IP interconnect devices.
c. Verify that the correct cross or straight-
through cable is being used. See
“Appendix F. IP Addresses”.
2a. Verify that portion of IP addresses
identified by Subnet Mask for both
local and remote NCBs are identical.
3a. Verify that IP routers and switches
have Multicast mode enabled.
b. Verify that IP routers are programmed
to pass the IP multicast address of the
NCB-Etherlon.
c. Verify that IP routers are programmed
to pass the NCB-Etherlon multicast
port numbers of 1100 (destination port)
and 1283 (source port).