Nautel NV3.5LT, Руководство по устранению неисправностей

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NV5LT/NV3.5LT TROUBLESHOOTING MANUAL RESPONDING TO ALARMS
PAGE 4.1.24 VERSION 3.3 2016-03-10
Module #: PA 1-4 Fail Power Amplifier (red) This alarm occurs if (1) the PA voltage for the suspect PA is greater than
16 V; (2) the RF drive level to the suspect RF power module (with failed PA)
is less than 10 W; and (3) if conditions (1) and (2) are met,
the dc input
current for the suspect PA has fallen below a preset threshold (typically less
than 50% of the average PA current of the operational PAs). This may be
caused by a cabling fault on the PA, loss of PA voltage, bias voltage or RF
drive, or a defective FET. The transmitter’s output power may be reduced,
depending on the power setpoint.
The alarm can also occur after initiating a Xmtr PA Bias routine, which is
required after replacing an RF power module or the controller module. In
this case the alarm indicates that the bias routine failed for the specified PA,
possibly as a result of a PA bias circuit failure or an actual PA failure.
Attempt to operate the PA in the desired mode. If the fault clears, the alarm
was likely caused by a PA bias circuit fault. If the fault remains and/or the
PA current levels are below average, it is likely a PA failure.
Module #: PS A (or B)
AC Fail Power Supply (red) This alarm occurs if one of the two module power supplies (1 or 2) is
reporting an ac failure, indicating its ac input voltage is less than 175 V ac.
If a bank of power supply modules are indicating an AC Fail alarm, it is
possible that an ac phase loss has occurred. Check the ac voltage applied to
the suspect power supply module. If the ac voltage is acceptable, replace
the module (see
“LVPS / Power Supply Module Replacement” on
page 4.1.46
).
Module #: PS A (or B)
Current Limit Power Supply (red) This alarm occurs if one of the two module power supplies (1 or 2) is
reporting a current limit, indicating that the power being delivered by the
module has reached 2750 W. This may relate to the operating mode and/or
the load impedance at the transmitter’s RF output. Check for other
transmitter related alarms.
Module #: PS A (or B)
Fail Power Supply (red) This alarm occurs if one of the two module power supplies (1 or 2) is
reporting a PS failure, indicating its output voltage is outside its acceptable
range, based on the control setting. Check the dc voltage output of the
suspect power supply module. If the dc voltage is out of tolerance, replace
the power supply module (see
“LVPS / Power Supply Module
Replacement” on page 4.1.46
). If the voltage is acceptable, suspect
the PS interface PWB (A1).
Device and
Alarm Name
(AUI, UI)
Front Panel LED
(color)
Description and Troubleshooting Action