HP 5890 Series II Plus Reference Manual page 93

Signal Output
Warn: and fault: messages
WARN: SIGNAL CHANGED and/or WARN: NO DETECTORS is
displayed if a detector previously assigned to a particular signal
channel is found to be absent; for example, if the signal board for a
given detector should fail or be removed for service.
FAULT: INET CPU is displayed if the processor (and/or its associated
circuitry) for HP 5890 INET operations should fail.
HP 5890 diagnostics generating the above message displays are active at
all times in normal operation. The next group appears only if a problem is
found to exist at HP 5890 power•on:
Remaining FAULT: INET messages are displayed if problems are
diagnosed in INET circuitry.
FAULT: ATTN1 TEST and/or FAULT: DAC1 TEST occur if problems are
diagnosed in signal path circuitry for a particular signal channel
(channel 1, in the example displays).
In general, if signal problems are suspected, power to the HP 5890 may
be turned off, and then on again to perform internal self•testing.
Appropriate message displays occur if problems are found to exist.
Note: In case multiple problems exist simultaneously, press
roll through NOT READY and/or FAULT: displays.
Note that, with exception of WARN: OVEN SHUT OFF,
displayed WARN: message.
For WARN: messages, the instrument remains operational, except for
the function indicated by the message: the message is erased upon
pressing any instrument function key (e.g.,
messages, in addition to the message, the red NOT READY LED blinks:
the instrument CANNOT be operated until the problem is corrected.
If a WARN: or FAULT: message occurs in normal operation, try
switching power to the instrument off, and then on again. If the problem
recurs when power is restored, service procedures are indicated.
CLEAR
erases any
CLEAR
). For FAULT:
OVEN TEMP
to
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