Troubleshooting Control Unit IV Reference Manual
6-14 529-0004 Ver.3
Unit powered off
If one of the units is off (switched off or has a faulty power supply), then the other unit will
indicate that its backup is absent. If the master unit is off, then the backup unit will take over.
If the backup unit is off, then the master unit will continue to operate as the master unit. In
both cases, you should resolve the power problem to ensure full redundancy. See section 6.1
to troubleshoot powering problems.
Master or backup unit:
Redundancy monitoring
system......OK
←
redundancy system is OK
Backup unit....NOT PRESENT
←
the unit has NOT detected another unit
(its backup)
6.4.6 Redundancy system toggle warning
When the message Warning from redundancy system: this unit is now MASTER (or
backup) appears, this means that the redundancy circuitry caused a toggle to the backup unit.
The transmission signals on COM 1 and on the
RF
OUT
output are cut off on the old master
unit. The toggle took place because the RF watchdog detected an error.
If you are logged on to COM 3 and a toggle has occurred, information regarding the
redundancy circuitry will be displayed each time the <Enter> key is pressed. These messages
appear because the redundancy failure notification is on. If no messages appear, then the
notification feature is off. To diagnose the problem:
1. Connect a terminal to COM 3 of the defective unit and establish a connection.
2. Turn off the defective Control Unit and then turn it back on. Read the startup screen to
see if there are any warnings or errors. If the message tells you that one of the systems is
defective, contact Electroline’s technical support department.
3. Repeat steps 1 and 2 on the other Control Unit.
4. If no system problem is detected, restart the units (see section 6.4.3).
5. If the problem persists, contact Electroline’s technical support department.
6.4.7 Redundancy system synchronization errors
In terminal mode, the Control Unit will notify the user if both units in a redundancy system
are not properly synchronized or if the units cannot be synchronized due to a hardware
problem.
Backup response error
1. If the message Backup response error appears, first try the command again. Since both
units must process the same data in a redundancy system, the response from the backup
unit must be identical to the response from the master unit. It is possible that a temporary
problem interfered with the processing.
2. If the message appears again, make sure that the redundancy cable and the
synchronization cable are properly connected, and that both Control Units have the same
setup.
To Next Page
Loading...