Cable AML ITX21-100, Руководство по установке и обслуживанию

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Indoor Broadband Transmitter – ITX21-100
IM4030013-1 Rev –
16
5.3 Internal Troubleshooting
Remove the cover of the transmitter.
WARNING
Internal troubleshooting requires that:
¾
Power remains on.
¾
Transmitter cover is removed.
1
CONTACT WITH LINE VOLTAGE CAN BE FATAL!
1
It is recommended that internal troubleshooting be limited to personnel skilled in
maintenance of microwave transmitters or receivers.
IF IT IS NECESSARY TO REPLACE COMPONENTS, THE REPLACEMENT OF PARTS
SHOULD BE DONE WITH THE EXTERNAL AC POWER DISCONNECTED
.
a
Internal Quick Check.
A quick check should show that the fan is operating and the power amplifier and its power
supply are warm to the touch.
Lack of +12 VDC
If internal trouble shooting is required due to lack of +12 VDC in the external DC
diagnostic test then check for in12 VDC on the terminal strips. If either of these
voltages is missing, first disconnect the wires from the power supply output terminals and
recheck the voltage.
If the power supply voltage with no load is not +12 VDC then the power supply is defective
and should be replaced.
If the voltage is normal, the load on the power supply is too high causing the supply to go
into crowbar and shut down. At this point, examine the wiring harness for an obvious
wiring fault. If no fault is found, then one of the modules supplied by that power supply is
shorted internally and should be replaced. To identify the module remove the DC power
wire for each module one at a time from the terminal block until the DC power bus is
restored to normal.