Thermo Scientific SAM12, Руководство пользователя

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Maintenance and Trouble Shooting Issue: 1.0
11-14 SAM12 User Manual Thermo Fisher Scientific
7. Switch unit OFF and replace the Controller board as
described in
Controller Board type 5670A - Removal
and Replacement (page 11-6) .
8. If the SAM12 is still dead after changing the Controller
board, contact Thermo-Fisher Service department for
further help.
If the SAM12 starts but fails to chime (“ding-dong”) within 60
seconds of being switched ON, then it has not successfully
completed the power-on Self Tests and a fault is indicated.
Observe the LCD display, if a fault message is displayed refer
to subsequent subsections. If, however, the display is blank or
the message is unintelligible, it is likely the Controller board
has a serious fault and the microprocessor has I/O problems or
has crashed. Replace the Controller board as described in
Controller Board type 5670A - Removal and Replacement
(page 11-6)
.
The blue FAULT lamp is lit (see
Fault Messages (page 11-1
)for an explanation of the fault messages). The Self Tests have
detected the background count from the detector channel is
below the Low
Background Alarm value set in Params 1 (page
5-8) . Proceed as follows:
1. Enter a valid password and Setup|Params 1. Check that
the Low Background Alarm is not set to an
unreasonably high value for the prevailing background
condition.
2. Select Calibration|HV Scan and check the HV settings
for each channel are correct.
3. Check the cable connections between the Controller
board and the HV & Amplifier pcbs.
4. Having performed checks 1 to 3 above, select
Diagnostics|Detectors Bar, perform a 10 second count
and check the faulty channel/s and note the counts.
Zero counts in a channel usually implies a complete failure in
either the detector assembly or HV/Amplifier PCB. A few
counts suggests either reduced detector efficiency or threshold
problems in the HV/Amplifier.
1. Swap the faulty detector MHV connection from the
relevant HV/Amplifier to that of a working channel.
Perform a further 10 second count and note the counts
in each channel.
2. If the fault moves with the detector into a previously
working channel, the fault is in the detector assembly
Starts-up but Display is
“Blank” & Fails Self Tests
(no chimes)
Will not run & displays
“Out Of Service – Low
Background Counts”