Nautel XR12, Troubleshooting Manual, Page: 64 / 283

XR12 Troubleshooting Manual Responding to alarms
Page 1-44 Issue 3.0 2009-07-28
2. Remove the two right-hand blank panels adjacent the RF power module(s). If the optional
third RF power module is installed instead of a blank panel, remove it (see “Removing and
reinstalling RF power modules” on page 1-21 ).
3. Remove the screws that secure the protective cover over the assemblies mounted on the
right-hand side of the cabinet (see Figure MD-1).Disconnect all cables attached to the low
voltage power supply assembly (A22), taking note of the connector labels on the cables and
the assembly.
4. Remove and save four sets of mounting hardware that secure the assembly to the side of the
transmitter.
5. Remove the assembly from the transmitter.
6. Reverse Step 1 through Step 5 to reinstall the replacement assembly.
+24 Volt Power Supply assembly replacement
See Figure MD-1.
1. Turn off the power at the source and wait (about 5 minutes) for the green LEDs on the B+
distribution PWB to turn off, indicating the capacitors are discharged (see Figure 1.9 on page
1-40 ).
2. Remove the two right-hand blank panels adjacent the RF power module(s). If the optional
third RF power module is installed instead of a blank panel, remove it (see “Removing and
reinstalling RF power modules” on page 1-21 ).
3. Remove the screws that secure the protective cover over the assemblies mounted on the
right-hand side of the cabinet (see Figure MD-1).Disconnect all cables attached to the +24 V
power supply assembly (A23), taking note of the connector labels on the cables and the
assembly.
4. Remove and save four sets of mounting hardware that secure the assembly to the side of the
transmitter.
WARNING:
Lethal voltages exist inside the transmitter when the power is turned
on. Turn off the power at the source and wait until the green LEDs on
the B+ distribution PWB are off before removing any connections or
PWBs (see Figure 1.9 on page 1-40 ).