Keithley 237

SECTION2
Operation
2.2.3
Power
Cord
Connect
the
female-end
of
the
power
cord
to
the
ac recep-
tacle
on
the
rear
panel
of
the
instrument. Connect
the
male-end
of
the
cord
to
a
grounded
ac outlet.
WARNING
The
Source
Measure
Unit
is
equipped
with
a
3-wire
power
cord
that
contains
a
separate
ground
wire
and
is
designed
to
be
used
with
grounded
outlets.
When
proper
connections
are
made,
instrument
chassis
is
connected
to
power
line
ground.
Failure
to
use
a
grounded
outlet
may
result
in
injury
or
death
due
to
electric shock.
CAUTION
Be
sure
that
the
power
line
voltage
agrees
with
the
indicated
range
on
rear
panel
line
voltage
switch.
Failure
to
observe
this
pre-
caution
may
result
in
instrument
damage
not
covered
by
the
warranty.
The
procedure
to
configure
the
instrument
for
the
alternate
line
voltage
is
found
in
paragraph
2.2.1.
2.2.4
Power
Up
Display
Messages
and
Self
Test
Turn
on
the
instrument
by
pressing
the
POWER
button.
During
the
power
up
cycle,
the
unit
will
perform
the
fol-
lowing:
1. The Source
Measure
Unit
will
perform
tests
on
its
memory
elements.
If
the
self tests fail,
one
or
more
error
messages will
be
displayed
and
operation
may
be
interrupted
until
the
problem
is resolved.
In
this
event, refer
to
the
service
manual
for troubleshoot-
ing
information. A brief explanation of
any
dis-
played
error
message is contained
in
Table 2-3 (see
paragraph
2.8).
NOTE
If
the
instrument
is
still
under
warranty
and
a
problem
develops,
it
should
be
returned
to
Keithley
Instruments,
Inc.
for
repair.
2.
Assuming
the
unit
successfully passes
the
self test,
it
will
then
briefly
display
the
software revision level.
For example:
SOFTWARE REV A04
2-4
+
+
The
revision level
of
your
unit
may
be
different.
In
any
case,
the
software revision level
should
be
re-
corded
in
case
it
becomes necessary
to
replace
the
ROMs
in
the
future.
3. Next,
the
programmed
primary
IEEE-488 address
will
be
displayed
as
in
the
following example:
IEEE ADDRESS 16
At
the
factory,
the
IEEE
address
of
the
Model
236/237/238
is
set
to
16.
If
the
address
has
been
changed
by
the
user,
then
that
address
value
will
in-
stead
be
displayed.
4.
The
unit
will
then
begin
normal
operation
in
accor-
dance
with
the
power
up
configuration discussed
in
the
next
paragraph.
2.2.5
Power
Up
Configuration
After
the
self testing
and
power
up
display messages are
completed,
the
Source
Measure
Unit
will
initialize to
spe-
cific
operating
conditions. This initialization is
summa-
rized
in
Table
2-5
(see
paragraph
2.10.8).
A checkmark
(--/)
indicates
that
the
unit
will initialize
to
whatever
was
pre-
viously
programmed.
The
Source Measure
Unit
will
go
to
the
factory default
conditions
when
the
Factory
!nit
program
is
run
or
JO
is
sent
over
the
IEEE-488
bus. Refer
to
paragraph
2.10.8
for
details.
2.2.6
Line
Frequency
Setting
The
instrument
will
operate
at
a line frequency of
50
or
60Hz.
In
order
for
the
Source
Measure
Unit
to operate
properly
for line cycle measurements, its line frequency
setting
must
match
the
frequency
of
the
power
line. To
check
or
change
the
line frequency setting
of
the
instru-
ment,
perform
the
following steps:
1. Press
the
MENU
button
on
the
keypad.
The
MENU
light
will
turn
on
and
the
first
item
on
the
menu,
which
is
de
delay
time,
will
be
displayed.
2.
Turn
the
rotary
knob
until
the
currently selected ac
line frequency is displayed. For example,
if
the
in-
strument
is
set
for
60Hz
operation,
the
following
message
will
be
displayed
on
the
menu:
60HZ
ACLINE
3.
The
alternate line frequency setting
can
be
selected
by
displaying
it
with
the
SELECT
buttons
and
then
pressing
ENTER