Nautel NX15, Troubleshooting Manual

Page: 22 / 274

NX25/NX15 Troubleshooting Manual Responding to alarms
Page 1-14 Issue 5.0 2016-05-06
Controller: Internal
Watchdog Reset This alarm will only be seen in transmitter logs, and indicates that
the controller was reset by its internal watchdog. If this alarm
persists, replace the control/interface PWB (see
“Control/interface
PWB replacement” on page 1-60 ).
Controller: Interlock
Open This alarm indicates that the external interlock input wired to the
control/interface PWB is open. An alarm will be triggered by user-
set conditions (e.g., the state of the door to the transmitter room).
When this alarm occurs, the transmitter immediately inhibits the
PDM and the transmitter's output power drops to 0 W. If this
condition persists for more than 10 seconds, the transmitter will
inhibit the RF power modules, fans and B+ power supply. The
transmitter will automatically recover when the condition is
cleared. With the transmitter set to RF Off, disconnect the
interlock circuit from the transmitter. Measure the impedance of
the interlock circuit. If the impedance measures open circuit (high
impedance) the interlock is open, and it will be necessary to locate
the external device that is causing this condition. If the impedance
does not measure open circuit, verify the interlock circuitry has
been properly configured. If the interlock circuitry is properly
configured, make a temporary jumper and use it to short out the
interlock circuit. If the alarm disappears, the transmitter is
operating as expected and it will be necessary to locate the
external device that is causing this condition. If the alarm persists,
replace the control PWB. See
“Controller: Interlock Open” on
page 1-41 .
Controller: Jumped to
Bootloader This alarm is only visible in the transmitter logs, and indicates the
controller was reset due to performing a firmware upgrade. If this
alarm is occurring when a firmware upgrade is not being
performed, replace the control/interface PWB
(see “Control/
interface PWB replacement” on page 1-60 ).
Controller: Low Battery This alarm occurs if the voltage of the backup battery has fallen
below an acceptable level. Replace the battery (BT1) on the
control/interface PWB while ac power is on. If the alarm persists
after replacing the battery, replace the control/interface PWB (see
“Control/interface PWB replacement” on page 1-60 ).
Alarm (with Prefix) Description and Troubleshooting Action