Nautel VS1, Руководство по устранению неисправностей

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VS1 Troubleshooting Manual Responding to alarms
Page 1-20 Issue 10.0 2018-10-29
No External
10 MHz
(No Ext
10MHz)
Exciter (amber) This alarm occurs if frequency locking to an external 10 MHz
souce is enabled and no external 10 MHz is detected. The exciter
will automatically switch over to the internal 10 MHz reference,
and will continue to run. Check the 10 MHz input. If there are no
problems with the 10 MHz signal and connection, suspect the
exciter/control PWB (A1).
No HD Data Exciter (amber) This alarm occurs, in FM+HD or HD mode, if IBOC data is not
detected from the VSHD exciter’s Exgine PWB. Digital carriers
are muted. Verify the RJ45 cable (W1) between the
XMTR LINK
(A1J2)
connector on the rear of the VS-HD exciter and the
XMTR
LINK (A1J1)
connector on the rear of the transmitter is seated
properly. Check that the Exgine PWB is correctly powered up.
No Internal
10 MHz
Exciter (red) This alarm occurs if no 10 MHz clock is being detected on the
exciter/control PWB (A1). This alarm will cause the transmitter to
shut-down and the exciter/controller PWB may not be running.
Replace the exciter/control PWB (see “Exciter/Control PWB
Replacement” on page 1-43 ).
PA 1 - 4 Fail PA (amber) This alarm occurs if the dc input current for the indicated PA has
fallen below a predetermined threshold (typically less than 50% of
the average PA current of the operational PAs, or below 500 mA,
whichever is lower). This may be caused by a cabling fault on the
PA, loss of PA voltage or bias, or a defective FET. The
transmitter's output power will be reduced (see Table 1.4 on
page 1-30 ) and this condition could cause
Per PA Foldback
and
Reject Foldback
alarms. Check for an
All Power Amplifiers
Inactive
alarm and follow the associated troubleshooting
procedure if present. If the
All Power Amplifiers Inactive
alarm
is not present, perform the “PA resistance checks” on page 1-34 .
If there is no problem found with the PAs, or the alarm still persists
after replacing the PA, suspect the PS distribution PWB (A2).
PA Over
Temperature
(PA Over
Temp)
PA (red) This alarm occurs when the temperature as measured by RT1 or
RT2 exceeds 70°C (158°F). This alarm will cause the transmitter
to shut down and latch off. Check for
Fan Fail
alarms and follow
the associated troubleshooting procedure if present. If no
Fan Fail
alarms are present, check the transmitter's air filter and clean or
replace as required (see Section 3, “Routine maintenance of the
Operations and Maintenance Manual). If the alarm persists,
suspect the exciter/control PWB (A1).
Alarm Name
AUI and
(Front Panel)
Front Panel
LED (color)
Description and Troubleshooting Action