Nautel VX150, Manual

Page: 18 / 105

VX150 TO VX2 TROUBLESHOOTING MANUAL RESPONDING TO ALARMS
PAGE 3.1.10 VERSION 0.1 2020-12-01
High SWR This alarm occurs if the transmitter's average reflected power exceeds the high SWR
threshold (
?? W ). The transmitter takes no action on this alarm. Inspect the antenna and
transmission line system for damage or de-tuning. If there are no major issues with the
antenna network that would cause an impedance change (icing for example),
suspect the
Combiner Interface PWB (see “Combiner Interface PWB Replacement” on page 1-50)output
power probe PWB (A7) (see “Output power probe PWB replacement” on page 1-45
).
High SWR Shutdown This alarm occurs if the transmitter tries to reduce the forward power below a level that is
equivalent to a 3:1 VSWR (forward power of
?? W ) at the SWR Foldback threshold (reflected
power of ?? W ) due to a gradually degrading load match. This alarm causes the transmitter
to latch off. Inspect the antenna and transmission line system for damage or de-tuning. If
there are no major issues with the antenna network that would cause an impedance change
(icing for example), s
uspect the Combiner Interface PWB (A12) (see “Combiner Interface
PWB Replacement” on page 1-50.
Host Not Booted This alarm indicates that the controller’s host has not finished booting. The remote AUI will
not yet be available. Occurrence of this alarm is normal for approximately one to five minutes
while the host is booting, immediately after ac power has been applied/restored or after a
software upgrade. If this alarm continues to occur more than 30 minutes after ac power has
been applied to the transmitter, cycle (turn off, then on) the ac power. If the alarm persists
after 30 minutes,
replace the Exciter/Control PWB (A1) (see “Exciter/Control PWB
Replacement” on page 1-46 ).
Host Not Responding This alarm indicates that the microcontroller (host) that runs the remote interfacing
applications is not communicating with the transmitter’s primary microcontroller (DSP). If the
watchdog function is enabled, the DSP will automatically reset the host. If this alarm persists
for more than 10 minutes, try cycling power (off, then on) to the transmitter. If the alarm
persists,
replace the Exciter/Control PWB (A1) if necessary (see “Exciter/Control PWB
Replacement” on page 1-46) .
IPA Failure This alarm occurs if the IPA Output Low alarm is present and the measured IPA current is
below
225 mA. The transmitter takes no action on this alarm. See IPA Output Low for
troubleshooting tips.
IPA Output High This alarm occurs if the pre-amp/IPA PWB's forward power is greater than the IPA Output
High threshold (
130%/36 W) . If this condition persists, replace the pre-amp/IPA PWB (A5)
(see “Pre-amp/IPA PWB replacemen t” on page 1-42). The transmitter takes no action on this
alarm. If this alarm persists after replacing the pre-amp/IPA PWB, s uspect the Combiner
Interface PWB (A12) (see “Combiner Interface PWB Replacement” on page 1-50) or the
Exciter/Control PWB (A1) (see “Exciter/Control PWB Replacement” on page 1-46)
.
Alarm Name Description and Troubleshooting Action