User Manual

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User Manual
• O
nce the discovery has finished, the general alarm (i.e. the LED “┌┘”)
on each TFLN panel stops blinking and switches OFF (provided that
the TFLN master optical TRX is not affected by a general failure).
TPRN troubleshooting
In case a TPRN sub-rack shows any problem a more detailed status and
alarm description could be provided through the remote supervision unit.
A complete overview of TPRN alarms is reported in the previous Table 5.4.
The power supply degradation occurs in case the +12Vdc power falls below
an in factory set threshold level. In this case, TPRN automatically turns to
standby mode so that no over-current gets through the circuitry of hosted
modules, thus preserving the system integrity. Once power supply has been
repaired, the TPRN needs to be rebooted. In case the TPRN sub-rack is
equipped with a redundant power supply (TPRN24), a degradation of the
+12 Vdc power results in an automatic switching from main to spare
converter. In case also redundant power supply degrades the TPRN
automatically turns to stand-by mode. Once the power supply has been
repaired the TPRN needs to be rebooted.
I
2
Cbus alarm occurs when TPRN sub-rack cannot communicate with one or
more hosted module. Each TPRN slot is able to automatically detect the
presence of a module inside the slot. If the module is detected but TPRN is
not able to communicate with it through I
2
Cbus alarm is activated.
Note
: at commissioning remember to mask the unused slots through LMT
software (please refer to the relevant manual for more information) to avoid
not significant alarm being switched on.
In order to carry out a troubleshooting procedure, please check LMT or
supervision system handbooks.
TPRN
Note: in case discovery doesn’t start automatically, check through the LMT or the
remote supervision whether it has been disabled (refer to LMT or remote supervision
system manuals for further information).