HP 8340b User Manual

LINE
MODULE
TROUBLESHOOTING
Refer
to Figure
1-6
in
REPAIR
PROCEDURES.
1.
Ensure
that
the
main
line
fuse
and
the selected
line
voltage
are
correct.
2.
Disconnect
line
power,
and
remove
the
instrument top
and
bottom
covers.
3.
Wait
for the
A19
power-on
safety
indicator to
go
out.
4.
Remove
the
portion
of the
rear
panel
that
holds
the
line
module:
a.
Remove two
screws
(item
12).
b.
Invert
the
instrument and
remove
three
rear
panel
screws
(item
7).
c.
Remove
the
ASS
assembly
protective
cover.
d.
Remove
three
rear
panel
screws
(item
13).
e.
Remove
the
fan.
f.
Remove
three
rear
panel
screws
(item
8).
g.
From
inside the
instrument,
push
the
rear
panel
out.
5.
Reconnect
line
power.
6.
If
the
line
voltage selector
cam
is
set
to
120
or
240
Vac,
measure
the
voltage
across
output
pins
C
and
E,
and
across
pins
D
and
F.
If
the
line
voltage selector
cam
is
set
to
100
or
220
Vac,
measure
the
voltage
across
output pins
A
and
F
(see
LINE MODULE
REPLACEMENT).
7.
The
voltage
across
these
pins
should
equal
the
selected
line
voltage.
If
no
voltage
is
present,
replace
the
line
module.
RECTIFIERS
AND
REGULATORS
+22V
is
the
only
completely
independent
power supply,
and
no
other
power
supply
directly
depends
on
it.
When 4-22V
comes
on,
LSBY
(low
standby)
goes
low,
triggering
the
+20V
supply.
The
+20V
supply does
not
directly
require
another
supply
to
operate,
but
all
other supplies
(except
+22V)
are
directly
or
indirectly
dependent
on
it.
There
are
other
power
supply
interrelationships
as
well:
•
The
+12V
supply
requires
both
the
+5.2
and
—5.2V
supplies.
•
The
—5.2V
supply
is
powered
by
the
—10V
supply.
•
The
—15V
supply
is
powered
by
the
—40V
supply.
To
determine
the faulty
rectifier
or
regulator when
multiple
supplies
are
down,
or
to
determine
if
a
single
supply
failure
is
caused
by
the
rectifier
or
regulator,
refer to
Figure
1-3.
1-10
Power
Supplies/Fan
Assembly-Level Troubleshooting
HP
8340B/41B

HP 8340b Specifications

General

Brand	HP
Model	8340b
Category	Inverter
Language	English