Nautel NX15, Troubleshooting Manual

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NX25/NX15 Troubleshooting Manual Responding to alarms
Page 1-42 Issue 5.0 2016-05-06
5. If 15 V is present on J6-5 and J6-1, the external interlock circuit is open (normally caused by
an open interlock switch).
Module faults
There are many alarms on the AUI, prefixed by the text
Module
, that indicate faults related to one or
more of the 10 RF power modules in a cabinet. The number that appears after Module or PM,
identifies the serial identification of the affected RF power module. These serial numbers are labeled
on the front panel of each RF power module.
1. Check the forward power reading on the AUI. If it is less than the preset level, one or more
RF power modules are defective. Proceed to “RF power module fault validation” .
2. If the forward power reading in Step 1 is normal press the
Transmitter Status
button on the
AUI to check for other alarms that may have triggered the RF power module alarm.
RF power module fault validation
Each RF power module has a multi-colour LED on its front panel, which can help in identifying a
fault and allowing you to determine whether remedial action is required now or later.
Identify and isolate a defective RF power module, and verify the nature of the defect by checking the
LEDs on the RF power modules’ front panels. Note which RF power module is not operating
normally and producing RF power (i.e., LED is not solid green). Record which RF power modules
are displaying an alarm and the state of its LED (see below).
– amber, off: module is RF off
– solid red: module has a non-latching alarm
– flashing red, then green: module is producing RF, but has an alarm
– long red, short amber: module has a latching alarm
– long red, short off: module has no valid serial number
– short red, long off: module has no valid serial address on the internal bus
– long amber, short green: module is producing RF, but no serial communications
– long amber, short red: module is not producing RF and no serial communications
Except in the case of a
High DC Current
,
High PA Volts
and
Residual PA Volts
alarm, attempt to
reset an RF power module by disconnecting and reconnecting the RJ45 plug in the front of the
module. If you cannot reset the front panel LED alarm, see
“RF power module troubleshooting” .