Agilent Technologies 6621A, Service Manual

Page: 54 / 156

Note that error number 22, SKIP SLF TST, is initially
generated when W201 is in the SKIP SELF TEST position.
This error is cleared when read. However, if an output
board fails the output board RAM or ROM tests which are
performed regardless of the W201 position, error number
11, 12, 13, or 14 (HDW ERR CH < ch >) is generated and will
be regenerated after the error is read since the problem still
exists.
Table 4-4 lists all of the self-test error messages that can
appear on the front panel display when power is first
turned on. Each message is explained and a troubleshooting
procedure is recommended. This table is to be used in
conjunction with Figure 4-6 and other troubleshooting flow
charts provided in this section.
4-16 Connector P201 Jumper Positions
with jumper positions that are used for normal operation of
the power supply or troubleshooting. The following
discussion describes the function of each of four jumper
positions.
+5 V NORM RUN: This jumper position is used as the
normal running position. The two
pins on P201 that W201 connects in
CAL. LOCKOUT:
This position is an alternate to the
NORM RUN position and is used to
ensure against accidental calibration
of the power supply. With W201 in
this position, error number 18 (CAL
LOCKED) is generated if an attempt
is made to turn on the calibration
mode (see Appendix A, in the
Operating Manual).
SIG. ANALYSIS: This position is used to perform
SKIP
SELF TEST: This position causes the power
supply to skip the power-on self tests
described in paragraph 4-15. This
attempt to power on all output
boards in the supply even if one or
more output would not have passed
self test.
Exercise care when using SKIP SELF TEST on a
unit with output boards that are known to fail self
test since the output may operate beyond its rated
parameters. The output voltage may even reach full
scale voltage without being programmed.
4-17 ERROR Codes and Messages
Table 4-5 lists all of the error codes and messages that can
occur when operating the supply. Each code and the
corresponding message (if applicable) are explained and a
remedy or troubleshooting procedure is recommended. This
table is used in conjunction with Figure 4-6 and other
troubleshooting flow charts provided in this section.
4-9
signature analysis on the GPIB board
for troubleshooting the GPIB board
(see para. 4-23).
position allows the GPIB board to
The GPIB board contains a connector (P201), see Figure 4-2,
this position are both tied to the GPIB
board + 5 V bias supply. The jumper
is simply stored in this position when
not used in one of the other positions.