NV5LT/NV3.5LT TROUBLESHOOTING MANUAL
RESPONDING TO ALARMS
VERSION 3.3 2016-03-10
PAGE 4.1.11
Controller: External
Interlock Open
(External Interlock)
Exciter (red)
The external interlock input wired to the controller (A4) or optional remote
interface PWB (A16), if used, is open. Check the interlock connection
between REMOTE I/O-A pins 19 and 20 on the controller (verify a ground
potential at pin 19) or optional remote interface PWB J2 pins 19 and 20 or
TB1-1 and 2. If the interlock is intact, check all external interlock switches.
Otherwise, suspect a problem with the interlock circuitry on the controller
or optional remote interface PWB.
Controller: External
Summary
-
Not displayed in AUI or UI status. Configurable as a remote output. This
alarm occurs if there are any external related alarms present. Check for
specific external related alarms and troubleshoot accordingly.
Controller: Forward
Power Limiting (Fwd
Power Limiting)
Output Network
(amber)
When the High Forward Power alarm is active, this alarm occurs if the high
forward power limiting threshold is exceeded [1.063 times the maximum
power setting for all modes; e.g., 5,846 W (NV5LT) or 4,384 W (NV3.5LT) for
FM mode]. The transmitter will fold back the forward power each time the
threshold is exceeded. This alarm occurs only if the exciter ALC cannot
respond fast enough to transmitter load changes. Suspect the module
control/interface PWB (A3).
Controller: Forward
Power Shutdown
(Fwd Power
Shutdown)
Output Network (red) This alarm occurs if the transmitter tries to reduce the forward power below
minimum due to repeated Forward Power Limiting alarms. The transmitter
latches off. See Controller: Forward Power Limiting for troubleshooting tips.
Controller: High
Forward Power (High
Fwd Power)
Output Network
(amber)
This alarm occurs if the transmitter’s average forward power exceeds the
high forward power threshold [1.036 times the maximum power setting for
all modes; e.g., 5,698 W (NV5LT) or 4,274 W (NV3.5LT) for FM mode]. This
alarm occurs only if the exciter ALC cannot respond fast enough to
transmitter load changes. Suspect the module control/interface PWB (A3).
Controller: High
Reflected Summary
Output Network
(amber)
Not displayed in AUI or UI status. Configurable as a remote output. This
alarm occurs if there are alarms present that are related to high reflected
power on the transmitter’s RF output. Check for specific reflected power
related alarms and troubleshoot accordingly.
Controller: High
Reject Power (High
Reject)
Output Network
(amber)
This alarm occurs if any of the transmitter’s reject loads’ average power
exceeds the high reject power threshold (1200 W). Typically, high reject
power is a result of RF power module failure or removal.
Controller: High RF
Drive
Exciter (red)
This alarm occurs if the RF drive power from the exciter is greater than the
high threshold (
45% a
bove the setpoint). This may be the result of a
calibration problem with either the exciter or the transmitter RF drive
sample. Check all connections to the exciter.
Device and
Alarm Name
(AUI, UI)
Front Panel LED
(color)
Description and Troubleshooting Action
Summary of Contents for NV3.5LT
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Page 8: ...NV5LT NV3 5LT TROUBLESHOOTING MANUAL PAGE 4 VIII VERSION 3 3 2016 03 10 ...
Page 294: ...VERSION 3 3 2016 03 10 SD 32 Figure SD 32 NAFP109B Output Power Probe and Sample PWBs ...
Page 307: ...VERSION 3 3 2016 03 10 MD 8 Figure MD 8 NAPA31C Power Amplifier PWB Q1 ...
Page 322: ...NV5LT NV3 5LT TROUBLESHOOTING MANUAL LIST OF TERMS PAGE 4 6 2 VERSION 3 3 2016 03 10 ...
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