NV5LT/NV3.5LT TROUBLESHOOTING MANUAL
RESPONDING TO ALARMS
PAGE 4.1.16
VERSION 3.3 2016-03-10
Controller: Reject
Foldback (Rej
Foldback)
Output Network
(amber)
This alarm occurs if any of the transmitter’s reject load
’
s’ average power
exceeds its reject power foldback threshold (1500 W). The transmitter’s
forward power will be reduced each time the alarm occurs, until the fault
clears. Typically, high reject power is a result of RF power module failure or
removal or PA power supply failure or removal. Check for associated alarms,
and follow the associated troubleshooting procedure if present.
Controller: Reject
Shutback
Output Network (red) This alarm occurs if any of the transmitter’s reject load
’
s’ average power
exceeds its reject power shutback threshold (1800 W). The transmitter will
be shut back and attempt to find a safe operating power level by entering
reject foldback mode. Typically, high reject power is a result of RF power
module failure or removal or PA power supply failure or removal. Check for
associated alarms, and follow the associated troubleshooting procedure if
present.
Controller: Residual
PA Volts Present
(Residual PA V Pres)
Exciter (red)
This alarm indicates that after the transmitter has turned off its RF output, it
is unable to discharge the PA volts to a level that is below 10 V. This
condition will not allow the transmitter to turn on its RF output; however
the condition will be cleared once the PA volts reaches a level that is below
10 V. This condition will typically occur with a failed PA or power supply
module. Check for associated alarms and follow the associated
troubleshooting procedure.
Controller: SRC1
Unlock
Exciter (amber)
This alarm indicates that no valid AES/EBU stream data is being detected on
the selected AES/EBU input. Check audio input cables. The NV5LT/NV3.5LT
takes no action on this alarm.
Controller: Standby
Exciter Test (Standby
Exc Test)
Exciter (amber)
This alarm occurs when a standby exciter test has been initiated by the user.
Exciter changeovers are inhibited during a standby exciter test.
Controller: SWR
Foldback
Output Network
(amber)
This alarm occurs if the transmitter's average reflected power exceeds the
SWR foldback threshold (200 W) due to a gradually degrading load match.
The forward power of the transmitter will be limited to a level such that this
threshold is not exceeded. If the load match improves while the transmitter
is producing RF output, the forward power will increase. If the transmitter
encounters a 3:1 VSWR (user-configurable) while in SWR foldback mode, an
SWR Shutdown alarm occurs. Inspect the antenna and transmission line
system for damage or de-tuning.
Device and
Alarm Name
(AUI, UI)
Front Panel LED
(color)
Description and Troubleshooting Action
Summary of Contents for NV3.5LT
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