Raytheon Beech Baron E55 - Page 538

ci5~eechcraft
BARON
55
AND
58
SHOP
MANUAL
j.
Reconnect
the
terminals
of the
airplane
system
b. After the
ground
and
power
circuits
have
been
wire
harness
to
the
same
designated
terminals
of
the
checked,
connect
a
jumper
wire between
pin
B of
the
modular
brush
assembly,
timer
receptacle
and terminal
B of
the
connector
plug,
and
from
pin
G
on
the
timer
receptacle
to
ground.
With
ELECTRIC
PROPELLER
DNCER
TIMER
the
deicing
system
switch
ON,
check the
voltage
to
ground
from
pin
B
of
the
timer.
The
voltmeter
should
CHECK
(GOODRICH)
rTE-
1182
AND
indicate
approximately
24
volts de when
the
airplane
AFTER,
TH-1231
THRU TH-1396
EXCEPT
battery
supply
is
being
used.
Next,
check the
voftage
TH-1369,
TC-2419,
JC-2450
AND
AFTER)
to
ground
from
pins
D
and
F,
the
points
at
which
the
system
voltage
is
impressed
in
sequence
to
cycle
Experience
in the
field has
indicated that often
the
timer
is
considered
inoperable
when the
source
of the
power
to
the
LH
and
RH
propeller
deicers. The
pres-
ence
of
24
vdc
system
voltage
should alternate
at
pins
trouble
is
elsewhere.
For
this
reason,
the
following
test
D and
F
for
90
seconds
in duration
as
the timer
should
be
performed
before the
timer
is
judged
to
be
cycles.
inoperable.
a.
With the
timer harness
plug
disconnected
and the
c.
After
a
voltage
reading
of
24
volts
DC
is
obtained,
deicer
switch
in
the
ON
position,
check
for
voltage
hold the voltmeter
probe
on
the
pin
until the
voltage
from
pin
B
of the
plug
to
ground.
If
no
voltage
is
drops
to
zero
before
moving
the
probe
on
to
the
next
present,
the timer
is
not
defective;
check the
power
pin
in
the
sequence.
Refer
to
Figure
11-40.
After
the
supply.
However,
if
system
voltage
is
present
at
pin
B,
correctness
of the
cycling
sequence
has
been
estab-
check
the circuit
from
the
harness
to
ground
with
an
lished,
turn
the
deicing
system
switch OFF
at
the
ohmmeter.
If
there is
no
continuity,
the
fault
is
in
the
beginning
of
one
of
the
"on-time"
periods
and
record
ground
circuit rather
than
the timer.
If the
ground
cir-
the
letter
of the
pin
at
which the
voltage
supply
is
cult
is
open,
the
timer
will
not
cycle.
present
to
facilitate
performance
of
the
following
test.
HEAT
TEST
(GOODRICH)
(TE-
1182
AND
AFTER,
TH-1231
THRU TH-1396
EXCEPT
TH-1389,
TC-2419,
TC-2450 AND
AFTER)
FWD
a.
Remove
the
jumper
wires that
were
installed
for
the
timer
test
and
reconnect
the timer
receptacle.
Two
SLIP
RING
ROTATION
men are
required
to
perform
this
test,
one man
in
the
SLIP
RI~G
ASSY
cockpit
to
operate
the
propeller
deice switch
and
observe
the
propeller
deice
ammeter,
the
other
on
the
ground
checking
the deice
boots
for
proper
heating.
t
7
f
b.
While the
person
in the
cockpit
observes the
1/32
INCH
MIN
2"
ammeter
for
a
reading
of
14
to
18
amps,
the
person
3/32
INCH
MAX
on
the
ground
checks
for
a
rise
in
heat
on
each
pro-
peller
deice boot
for
approximately
90
seconds
on
each
side.
c.
If
either boot
fails
to
heat,
check
the circuit
I~
I
between
the timer
and the
propeller
deice
boot
for
continuity.
BRusuMoouiEassv
i
u\uno~f
CAUTION
While
following
the
instructions
of
the
"HEAT
TEST"
section,
move
the
propel-
I
Figure
11-30.
Modular
Brush
Assembly
ler
back and forth
to
prevent
arcing
Installation
between
the
brushes
and
slip
ring.
11-58
515