Nautel NG1000, Troubleshooting Manual

Page: 29 / 164

NG1000 Troubleshooting Manual Responding to alarms
Issue 0.4 2010-10-12 Page 1-7
Table 1.1: Troubleshooting Alarms
Alarm (with Prefix) Alarm/Status LED Description and Troubleshooting Action
System Controller Generated Faults
AIn1(J11A-11) Fault EXTERNAL This alarm occurs when the analog input applied to the
auxiliary analog input 1 (pin 11 on
AUX I/O connector
A1J11A) is in an alarm sensing condition, based on a
threshold defined by the user.
AIn2(J11A-12) Fault EXTERNAL This alarm occurs when the analog input applied to the
auxiliary analog input 2 (pin 12 on
AUX I/O connector
A1J11A) is in an alarm sensing condition, based on a
threshold defined by the user.
AIn3(J11A-13) Fault EXTERNAL This alarm occurs when the analog input applied to the
auxiliary analog input 3 (pin 13 on
AUX I/O connector
A1J11A) is in an alarm sensing condition, based on a
threshold defined by the user.
AIn4(J11A-14) Fault EXTERNAL This alarm occurs when the analog input applied to the
auxiliary analog input 4 (pin 14 on
AUX I/O connector
A1J11A) is in an alarm sensing condition, based on a
threshold defined by the user.
Auto Chgover Event CONTROLLER This alarm occurs when an automatic transmitter
changeover occurs, typically due to the active
transmitter’s forward power falling below a preset
threshold. Check and troubleshoot the associated
transmitter for faults that may have caused the
changeover. Reset this alarm using a manual
changeover command or alarm reset.
Carrier Fault CONTROLLER This alarm occurs when the carrier frequency is off the
desired frequency by a preset amount (typically
12.5 kHz, or half a channel spacing).
Coax Interlock Open EXTERNAL This alarm occurs when the RF coaxial switch’s
internal interlock circuit is open. The system RF output
is inhibited by opening the associated transmitter
interlock circuits. If the troubleshooting tips do not
clear the alarm, replace the RF coaxial switch (see
“RF Coaxial Switch Replacement” on page 1-26 ).