Nautel V10, Руководство пользователя по установке и эксплуатации

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V10/V7.5/V5/V3.5 Installation and Operation Manual
Page 5-9
Section 5 System Level Troubleshooting Issue 3.5
•
reaching an acceptable level, but
continually dropping to 0 W, see
paragraph 5.5.1.1.2 'Exciter Output
Load Fluctuation'.
•
stable and within acceptable limits
[above 12 W (6 W) for analog
configured V10/V7.5 (V5/V3.5) or 6 W
(3 W) for digitally configured V10/V7.5
(V5/V3.5) and below 38 W for
V10/V7.5 or 19 W for V5/V3.5 in
FM
mode], the problem may be the RF
drive monitor protection circuitry on the
control/display PWB (A43) or a
defective component on the RF drive
splitter/changeover PWB (A16A1). In
dual exciter transmitters, if a
changeover occurred and the reserve
exciter is operating without alarm, then
the problem must be exciter related.
Refer to the associated exciter’s
manual.
NOTE
If it is necessary to check the control/
display PWB's (
A43 ) RF drive monitor
circuitry, refer to the Repair manual to
isolate circuit defects.
5.5.1.1.1 Low RF Drive
The exciter power has fallen below the low
RF drive threshold. Increase the exciter
output power until it reaches 20 W (10 W)
for analog configured V10/V7.5 (V5/V3.5)
transmitters or 10 W (5 W) for digitally
configured V10/V7.5 (V5/V3.5) transmitters
operating in
FM mode.
5.5.1.1.2 Exciter Output Load
Fluctuation
A problem may exist with the RF drive
splitter/changeover PWB (A16A1). If no
problem is found with the RF drive splitter/
changeover PWB, the problem is likely
exciter related. Refer to the exciter’s
manual for further troubleshooting
information.
Possible Associated Faults:
- IPA Input Pwr Low
5.5.1.2 IPA Input High
An IPA Input Pwr High alarm, although
unlikely, occurs if the input RF drive
(exciter power) to the active IPA module
exceeds the high RF drive threshold [
IPA
Input High threshold is user definable, but
is defaulted to 38 W for V10/V7.5 or 19 W
for V5/V3.5 in
FM mode; the threshold is
25 W for V10/V7.5 and 13 W for V5/V3.5
in
FM+HD or HD mode]. This alarm
occurs if ALC cannot respond fast enough
to varying exciter load changes, or if ALC
is disabled, or if the exciter’s output has
increased to a very high level.
•
Verify ALC is enabled on the exciter.
•
Compare the exciter’s programmed
level to its actual output. If there is a
significant difference, an exciter
regulation problem may exist. Refer to
the exciter’s manual.
NOTE
The control/display PWB's (A43) RF drive
monitor circuitry generates an exciter
interlock control signal to mute the exciter's
RF output for a predetermined delay. This
signal is generated each time the exciter's
output exceeds its high power threshold.
Possible Associated Faults:
- IPA Input Pwr High
5.5.1.3 Exciter Communication Failure
An Exciter Comm Fail alarm occurs
when communication between the
transmitter and exciter has failed
(M50
exciter only) . Troubleshoot an Exciter
Comm Fail alarm as follows:
NOTE
During an Exciter Comm Fail fault
condition, the Check Exciter and Exciter
Fault alarms (see paragraphs 5.5.1.4 and
5.5.1.5) are disabled and will never be
displayed by the transmitter, as these
alarms depend upon communication with
the M50 exciter.