Electroline Control Unit IV, Reference Manual

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Troubleshooting Control Unit IV Reference Manual
6-6 529-0004 Ver.3
6.3 Checking communications
6.3.1 COM ports
Note for redundancy systems:
To obtain troubleshooting help for COM port problems in a redundancy system, see
section 6.4.1 on page 6-8.
If you are unable to communicate with a host computer (or a terminal) that is connected to
one of the ports, then you may have a problem with the port setup on the Control Unit or on
the host computer, or there may be a hardware problem with the Control Unit.
1. First check the connections.
•
All cables should be connected properly and the screws securing the connectors
should be tightened.
•
Make sure you are using the right cable. Use a standard RS-232 cable to connect a
DTE type device such as a computer, or use a null modem cable to connect a DCE
type device such as a modem. See Appendix B for more information on cables.
2. If there are no problems with the cables, but you still cannot connect to COM 3, or if you
cannot connect to any of the Control Unit’s communication ports, check COM 3 first by
resetting the Control Unit, or in a redundancy system, by powering off the units, then
powering them back on (see section 6.4.3 on page 6-10).
•
If the
RX
/
TX
3
LED does not flicker briefly when the Control Unit is reset, then
COM 3 is not working. Contact Electroline’s technical support department for
specialized maintenance.
•
If the
RX
/
TX
3
LED flickers at reset, then COM 3 is working. You should now be able
to log on to COM 3, unless there is a problem with the setup on the host computer.
Check your host computer’s settings and your communication software. See
Chapter 3 for the mandatory port settings on COM 3.
3. If you can log on to COM 3, but you cannot log on to the other ports (COM 1 and
COM 2), a setup session may still be open, thus preventing communication. Exit the
session by typing
s
to save the setup and quit.
4. If the problem persists on the Control Unit’s COM 1 or COM 2 port even after exiting
the setup session, check the setup on these ports (see Chapter 3 for COM port setup). In
order to establish a connection, the Control Unit’s port and the host computer’s port must
have the same settings. If necessary, modify the settings on either the Control Unit or the
host computer so that they match. Double check that the right protocol and flavor (type)
are installed. If you are using the ICOR protocol on the COM port, make sure that the
Control Unit’s ID code is correct, or change it (see Chapter 3).
5. If the ports are set up properly, make sure that the host computer’s port is not being used
by another application or device. You may need to reboot Windows to free up the
computer’s ports.
6. If you are still unable to establish a communications link, contact Electroline’s technical
support department.