Power Cord; Instrument Cooling; Start-Up - Tektronix 2432 Service Manual

POWER CORD
This instrument has a detachable three-wire power cord
with a three-contact plug for connection to both the power
source and protective ground. The power cord is secured
to the rear panel by a cord-set securing clamp. The
protective ground contact on the plug connects (through
the power cord protective grounding conductor) to the
accessible metal parts of the instrument. For protection
against electrical shock, insert this plug into a power-
source outlet that has a properly grounded protective-
ground contact.
Instruments are shipped with the required power cord
as ordered by the customer. Information on the available
power cords is presented in Table 2-1, and part numbers
are listed in "Options and Accessories· (Section 7). Con-
tact your Tektronix representative or local Tektronix Field
Office for additional power-cord information.
INSTRUMENT COOLING
To prevent instrument damage from overheated
components, adequate internal airflow must be maintained.
Before turning on the power, first verify that air-intake
holes on the bottom and side of the cabinet and the fan
exhaust holes are free of any obstruction to airflow. The
scope has a thermal cutout that will activate if overheating
occurs. The scope shuts down immediately with no
attempt to save waveforms or front-panel conditions if a
cutout happens. Power will be disabled to the scope until
the thermal cutout cools down, at which time the power-on
sequence is redone. The resulting loss of the last front-
panel and waveform data will cause the power-on self test
to fail and is indicated to the user by a failed CKSUM-
NVRAM test (number 6000 in the main EXTENDED DIAG-
NOSTICS menu). The cause of the overheating must be
corrected before attempting prolonged operation of the
scope. Pressing the MENU OFF/EXTENDED FUNCTIONS
button restores the scope to the normal operating mode.
START-UP
This instrument automatically performs power-up tests
each time the instrument is turned on. These tests provide
the highest possible confidence level that the instrument is
fully functional. If no faults are encountered, the instrument
Preparation for Use-2432 Service
will enter the Scope mode in the either ACQUIRE or SAVE
Storage mode, depending on the mode in effect when it
was powered off.
If tests are failed, the scope displays the Extended
Diagnostics menu. If the failure is in the range of 1000-
5300 and the message "HARDWARE PROBLEM-SEE
SERVICE MANUAL" is displayed with the menu, see
"Diagnostics· in Section 6 for more information. If the
failure is in 1000-5300 range, but "RUN SELF CAL WHEN
WARMED UP" is displayed, the SELF CAL procedure
should be executed from the EXTENDED FUNCTIONS
menu (wait for the NOT WARMED UP message to disap-
pear from the SELF CAL menu). If failures persist after the
SELF CAL is run (the "HARDWARE PROBLEM-SEE
SERVICE MANUAL" message will be displayed), see
"Diagnostics· in Section 6 for more information.
Failure of a test in the range of 7000 to 9300 may not
indicate a fatal scope fault. Several conditions can occur
that will cause a non-fatal failure of the tests. The scope
will display "RUN SELF CAL WHEN WARMED UP" to
indicate a SELF CAL should be performed. If SELF CAL
does not clear the failure ("HARDWARE PROBLEM-SEE
SERVICE MANUAL" is displayed), the scope may still be
usable for your immediate measurement purposes. For
example, if the problem area is in CH 2, CH 1 may still be
used with full confidence of making accurate measure-
ments. Press the MENU OFF/EXTENDED FUNCTIONS
button to
exit
EXTENDED DIAGNOSTICS and enter
Scope mode.
NOTE
The SELF CAL procedure is detailed in Section 5 of
this manual. Refer to Section 6 of this manual for
information on the power-up tests and the pro-
cedures to follow in the event of a failed power-
up test.
A fatal fault in the operating system will cause the
scope to abort. No displays are possible, and the user is
notified of an abort situation only by the flashing of the
Trigger LED indicators (if that is possible). Cycling the
power off then back on may clear the problem, but a
failure of this magnitude usually requires the scope to be
referred to a qualified service person for checkout and
repairs. Persistent or reoccurring failures of the power-on
or self-diagnostic tests should be brought to the attention
of a qualified service person at the first opportunity. Con-
sult your service department, your local Tektronix Service
Center, or nearest Tektronix representative if further assis-
tance is needed.
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