Crown PSA-2 - Page 103

SAZPSA2041280
SUBJECT: Thermal Sense Chip Change
SERIAL NUMBERS AFFECTED; SN 10000-11343 (PSA-2}) 111947-112551 (SA-2)
On
each
SAZ/PSA2Z
output
module
is
a
thermal
sensing
chip
(U300/U400).
Because
of
availability
problems
of
the
metal
case
chip,
we
are
going
to
the
same
cir-
cuit
in
a
plastic
case.
The
old
part
number
is
C
5067-1.
When
changing
the
thermal
sense
chip
(metal
type)
on
the
above
serial
number
group,
the
following
parts
and
instgllation
procedures
are
essential:
QUANTITY
CPN
DESCRIPTION
1
C
5826-0
Thermal
Sense
Chip
1
W
9351-3
Teflon
tubing
3/8"
(.375)
length
q
BD
5064-7
Kapton
Insulator
Step
1.
Install
the
teflon
tubing
(CPN
W9351-3)
on
the
middle
lead
of
the
chip
(fig.3)
Step
¢..
Bend
all
leads
up
the
face
or
flat
surface
of
the
chip
so
leads
are
extending
above
the
chip
(fig.
2).
Step
3.
Insert
the
chip
into
the
Kapton
Insulater
(fig.
2
and
3)
used
to
insulate
the
thermal
sense
leads
from
the heat
sink
Step
4.
Insert
the
chip,
wrapped
with
the
Kapton
Insulator,
into
the
heat
sink
with
Flat
surface
of
chip
facing
D
303
(positive
module)
or
0
403
(negative).
Step
5.
Cut
the
Kapton
Insulator
vertically
in
two
places
(fig.
2),
fold
the
cut
portions
flush
against
the
heatsink
and
remount
printed
circuit
board.
Step
6.
Solder
the
heat
sensing
chip
leads
to
their
respective
trace
(fig.
4).
Dave Engstrom
Product Specialist
DRE/ Jao
i
i