AR 10046836, Operating And Service Manual

Page: 53 / 62

Model 500W1000C
Rev A 33
4.3.1 General - Reading Faults
The Model 500W1000C incorporates relatively simple fault detection circuitry, which makes use of the digital
display panel to alert the user or technician which component(s) need service. Use of these indications can
usually expedite troubleshooting of the amplifier. Most faults can be immediately determined down to the
assembly level. If a reset is still indicated, turn off the RF power signal to the input of the amplifier, read and
record the fault indication displayed on the digital control panel for later reference. Then, use the RESET
function to see if the fault clears. If the fault clears, slowly bring the amplifier’s drive level back up and ensure
that recommended RF power levels are not exceeded. If the fault indication is no longer visible, the fault may
have been brought about by a temporary transient condition, component thermal condition or excessive RF
drive to the amplifier’s input. If the fault does not clear with the RF drive off, some other problem exists in the
amplifier.
The digital control panel of the 500W1000C indicates the output power from the 500W1000C and the power
reflected back to it. If the reflected power is very high, with respect to the forward power, this could indicate
that the output coax cable is defective or that the load being driven has a high VSWR.
4.3.2 The Unit Cannot Be Operated Remotely
1. Verify that the front panel key-switch is set to the REMOTE position.
2. Verify that the unit operates locally by setting the key-switch to the LOCAL position; if the unit does not
operate locally, see 4.3.1 of this manual.
3. Check the position of the ADDRESS via the control software on the front panel touch screen as shown in
Figure 2-3 herein. (See Section 2 of this manual for the proper ADDRESS settings.)
4.3.3 Thermal Fault (Schematic Diagram No 10045618)
During a Thermal Fault, the front panel display should read THERMAL FAULT.
1. Try to reset the unit; if the unit resets and operates normally, check to see that the cooling fans are operating
normally and that the air inlet on the bottom of the unit and the air outlets on the rear of the unit are not
blocked.
2. If the unit does not reset and the cooling fans are operating normally, check the voltage at the A18A3 Switch
Breakout Assembly, J5, Pins 19-27.
3. If the voltage on A18A3 J5, Pins 19-27 is low, check the thermal sensor to the designated module.