Nautel XR12, Руководство по устранению неисправностей, Страница: 46 / 283

XR12 Troubleshooting Manual Responding to alarms
Page 1-26 Issue 3.0 2009-07-28
Special Tools
Required special tools:
• A torque wrench with a torque range of 0.0 to 2.26 N-m (0 - 20 in.-lbs). Required for install-
ing MOSFET attaching hardware.
• A 5 mm (0.197 in.), hex, thin-walled socket, with the same size drive as the torque wrench.
The outside diameter of the socket must be less than 7 mm (0.275 in.).
• A 5 mm (0.197 in., hex nut driver. The diameter of the outside wall must be less than
7 mm (0.275 in.).
• A 2.5 mm (0.098 in.), hex screw driver (Nautel part # HAZ65), included in the ancillary kit.
Electrostatic Precautions
The RF power module contains semiconductor devices that are susceptible to damage from
electrostatic discharge. Be sure to follow the electrostatic precautions in
“Electrostatic protection” on
page 1-3 at all times.
Fault Alarm Response
If possible, determine which LEDs on the front of the RF power module were turned on prior to its
removal from the transmitter.
• If it is not known which front panel LEDs were on, or if none were on, proceed to “Prepa-
ration for testing” on page 1-27 .
• If the
RF Drive
LED was on, connect the module to the test cable (see “Test cable
connection” on page 1-30 ) and perform the “RF drive tuning check” on page 1-36 . If the
problem persists after tuning, suspect the module’s RF drive control PWB.
• If the
Temp/Inhibit
LED was on, connect the module to the test cable (see “Test cable
connection” on page 1-30 ) and perform the “Temp/inhibit check” on page 1-36 .
• If one or more
Block
LEDs were on, proceed to “Preparation for testing” on page 1-27 .
NOTE:
If the digital multimeter does not have diode checking capability, a dc voltage source (9 V dc
battery) is required to turn on MOSFETs during troubleshooting procedures.