Keysight E3631A, Service Manual

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Service 5
Keysight E3631A Service Guide 115
Self-Test Procedures
Power-On Self-Test
Each time the power supply is powered on, a set of self-tests are performed.
These tests check that the minimum set of logic and measurement hardware are
functioning properly. The power-on self-test performs checks 601 through 604
and 624 through 634. For serial MY53xx6xxx, the power-on self-test utilizes the
complete self-test, which covers error codes 601 through 634.
Complete Self-Test
Hold any front panel key except the "Error'' key for more than 5 seconds while
turning on the power to perform a complete self-test. The power supply beeps
when the test starts. The tests are performed in the order shown below.
601
Front Panel Does not respond The main controller U17 (U10 for serial
MY53xx6xxx) on the top board attempts to establish serial communications with the
front panel controller U7 (U602 for serial MY53xx6xxx) on the front panel board.
During this test, U7 (U602 for serial MY53xx6xxx) turns on all display segments.
Communication must function in both directions for this test to pass. If this error is
detected during power-on self-test, the power supply will beep twice. This error is
only readable from the remote interface.
602
RAM read/write failed This test writes and reads a 55h and AAh checker board
pattern to each address of ram U15 (on-chip RAM for serial MY53xx6xxx) on the
top board. Any incorrect readback will cause a test failure. This error is only readable
from the remote interface.
603
A/D sync stuck The main controller issues an A/D sync pulse to U17 and U16 on
the top board to latch the value in the ADC slope counters. A failure is detected when
a sync interrupt is not recognized and subsequent time-out occurs.
604
A/D slope convergence failed The input amplifier is configured to the measure zero
(MZ) state in the 10 V range. This test checks whether the ADC integrator produces
nominally the same number of positive and negative slope decisions (±10%) during a
20 ms interval.
Cannot calibrate rundown gain This test checks the nominal gain between
integrating ADC and the U17 on-chip ADC. This error is reported if the procedure
cannot run to completion due to a hardware failure.