Nautel V10, Руководство пользователя по установке и эксплуатации

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Page 5-20
V10/V7.5/V5/V3.5 Installation and Operation Manual
Issue 3.5 Section 5 System Level Troubleshooting
•
If no voltage is present, check for a hot
PTC [RT11 (B11) or RT12 (B12)] on
the fan distribution PWB (A12). If the
associated PTC is hot, suspect a faulty
fan or wiring defect.
•
When a fan is defective, replace it with
a functional fan (see 5.6).
Possible Associated Faults:
- Comb Top Fan Fail
- Comb Bot Fan Fail
5.5.4 Low Voltage Power Supply
Alarm
A Low Voltage Power Supply alarm
occurs if the LVPS modules (U11 for
single LVPS transmitters; U11 and U12
for dual LVPS transmitters) fail, the active
fan supply fails, or a fault occurs in the
control/display PWB’s failure detection
circuitry. Troubleshoot a
Low Voltage
Power Supply alarm as follows:
NOTE
If the alarm lamp is still on after each step,
the fault remains. Continue troubleshooting
at the next paragraph. If transmitter
operation is restored and the alarm lamp
turns off, the fault has been cleared.
In dual fan PS transmitters, when a Low
Voltage Power Supply alarm is caused by
a faulty fan PS, an automatic changeover
to the standby fan PS is initiated.
Before attempting to troubleshoot a
suspect fan PS, inhibit further fan PS
changeover by setting Auto to N in the
Changeover menu. When troubleshooting
is complete, restore these settings to their
factory settings.
5.5.4.1 LVPS Fault
An LVPS Fault occurs if the LVPS
modules (U11 for single LVPS
transmitters; U11 and U12 for dual LVPS
transmitters) fail, resulting in an out-of-
tolerance dc power supply voltage(s)
(+5 V, +15 V, or -15 V). Troubleshoot an
LVPS Fault as follows:
NOTE
In dual LVPS transmitters, the LVPS
modules [A (U11) and B (U12)] are
connected in parallel (not as active/
reserve). Both modules must fail to cause
an LVPS Fault. It is likely the failure of
these modules will also disable the GUI’s
operation, making troubleshooting difficult.
(a) Verify ac is being applied to the
suspect LVPS module(s) and is in the
acceptable range (95 – 264 V ac).
(b) Measure the dc outputs of the suspect
LVPS module(s). If the outputs are
present, suspect a problem on the
control/display PWB (A43). Verify that
jumpers E2, E3 and E5 are installed,
that LEDs DS1, DS2, DS4 are on
(green). Check wiring to the control/
display PWB (supply voltages are on
D-sub connector P79, mates with J6).
(c) When the fault has been isolated,
either repair wiring, control/display
PWB or replace the LVPS module.
•
Press RF Off and switch ac off at the
service entrance.
•
Remove wiring from terminals on the
LVPS (A and B, as applicable).
•
Remove the LVPS module(s) by
removing its four M5 Phillips screws.
(d) Install operational LVPS module(s) and
replace/reconnect wiring. Switch the ac
on at the service entrance and return
the transmitter to ‘on-air’ operation.
Possible Associated Faults:
- LVPS Fault