Nautel VX150, Manual

Page: 21 / 105

VX150 TO VX2 TROUBLESHOOTING MANUAL RESPONDING TO ALARMS
VERSION 0.1 2020-12-01 PAGE 3.1.13
PA Power Supply AC Fail This alarm occurs if the power supply module (U3) is reporting an ac failure, indicating its ac
input voltage is less than
175 V ac . The transmitter will inhibit its RF output until the alarm is
cleared. Check the ac voltage applied to the power supply module. If the ac voltage is
acceptable, try replacing the indicated power supply module with a new module (see
“Power Supply Module Replacement” on page 3.1.23
). If replacing the power
supply module does not clear the fault, suspect the PS Distribution PWB (A2 ).
PA Power Supply Current
Limit Foldback
PA Power Supply Fail This alarm occurs if the power supply module (U3 is reporting a PS failure, indicating its
output voltage is outside of its acceptable range. The transmitter will inhibit its RF output
until the alarm is cleared. Try replacing the indicated power supply module with a new
module (see
“Power Supply Module Replacement” on page 3.1.23
). If replacing the
power supply module does not clear the fault, suspect the PS Distribution PWB (A2) or the
Exciter/Control PWB (A1) .
PA Power Supply Not
Compatible
PA Power Supply Not
Detected This alarm occurs if the power supply module (U3) is not being detected or has been
removed. The transmitter will inhibit its RF output until the alarm is cleared. If there is a
power supply module in the transmitter, try re-seating it or replacing it with a new module
(see
“Power Supply Module Replacement” on page 3.1.23
). If replacing the power
supply module does not clear the fault, suspect the PS Distribution PWB (A2 ).
PA Power Supply Over
Temperature This alarm occurs if the power supply module (U3) is reporting a high temperature alarm,
indicating its operating temperature has exceeded its internal threshold. The transmitter will
inhibit its RF output until the alarm is cleared. This alarm is most likely caused by a module
fan failure or blockage. Allow the module to cool and attempt to reset the alarm. Verify the
module turns on and its fan is operational. If the fan is not operational, inspect it for possible
blockage. If a problem is found, replace the power supply module (see
“Power Supply
Module Replacement” on page 3.1.23
). If there is no problem found, inspect the
transmitter’s front air filter and clean or replace as required (see Section 3, “Routine
maintenance of the Operations and Maintenance Manual). If the alarm persists, replace the
power supply module (see
“Power Supply Module Replacement” on page 3.1.23
). If
replacing the power supply module does not clear the fault, suspect the PS Distribution PWB
(A2).
PA PS Current Limit
Foldback This alarm occurs if the transmitter is limiting its output power to avoid drawing excessive
current (
?? A) from the power supply module. This may occur when there are PA failures and
the transmitter is attempting to compensate to attain the setpoint level. Check for associated
alarms, and follow the associated troubleshooting procedure if present.
PA Volts Failure This alarm indicates the PA voltage from the power supply module does not match the
requested setpoint. This is likely caused by a power supply module failure. Check the power
supply module (U3) and replace if necessary (see
“Power Supply Module Replacement”
on page 3.1.23
).
Alarm Name Description and Troubleshooting Action