Operating instructions
ADJUSTMENTS
Continued
4. Bring
set
pointer
(B)
in alignment
with
indicating
pointer
(C).
5.
Adjust
screw
(L)on
the
rear
switch
to a
point
midway
between
the two
positions
where
switch
(K)clicks.
For Wider
Differentials
(Up
to 112
Scale Length)
1. Remove front
cover,
top cover, and
temperature
^^^t^
òucilü.
2. Adjust
screws
(H)and (L)to
achieve 1/8 in
(3
mm)between
switch bracket and case shelf.
3.
Turn
set
pornter
(B)
to
extreme
left.
4. Raise
lever
(F)with
a screwdriver
to move
indicating
pointer
(C)
to
midscale.
5, Turn wide
differentiai
screw
(G)so
that rear
switch
just
actuates.
6. Turn
screw
(G)
counter-clockwise
amount
shown in Table tr*r"
,
Differential Sc¡ewTurns
3-15%
12-23%
2341%
4r-52%
Example:
125"F
diferential
in an
instrument with
50-700"F scale is
approximately
20% of scale
length, since
(125/650X1000Á)
:
approximately
-
19%. Therefore
turn screw
1 turn.
7 Repiace temperature scale.
B.
Align
set
pointer
(B)
with indicating
pointer
(C).
9.
Determine which switch
is to be indicated.
10. Loosen
set screw
(P)
and
rotate
pulley
on shaft
untilthe switch
to be
indicated
just
actuates.
Tighten set screw.
11.
Check settings
by
simulating
temperature
changes
with the screwdriver
under
lever
(F).
Trim by adjustments
to screws
(H)and
(L).
Model 4O-7O4
(See
Figure 5)
When
set
pointer
(B)
is in exact
alignment
with
temperature indicating
pointer
(C),
the
REAR
switch should be
midway
between
the
Operate
and
Reset
positions.
When
set
pointel
(J)
is in
exact
alignment
with temperature
indicating
pointer
(C),
the
FRONT swilch
shouid
be
midway between the
Operate and
Reset
positions.
The Operate
position
is the
point
where the s:witch
clicks
on;
the Reset
positions
is the
point
where
the switch
clicks off .
The relationship wÍll usually
be upset
if
the
snapswitch
is replaced,
but
is easily
restored
as
folÌows:
1. Remove
top coveI.
2. Bring set
pointer
(B
or J) in alignment with
indicating
pointer
(C).
3.
Adjust screws
(E)
midway
between
the
two
positrons
where
each
switch
clicks.
4.
Check
the setting by
placing
a
screwdriver
under
lever
(D)and
simuiate
temperature
changes by
moving the lever.
5.
If
necessary,
trim the
setting
by
slight
adjustment
of screws
(E).
Figure
5
Explosion-proof
Housing
(See
Figu¡e
6)
When the set
pointer
(B)
is in exact alignment with
indicating
pointer
(C),
switch
(J)
should be midway
between
the Operate
and
Reset
positions.
The
Operate
position
is the
point
where the
swrtch clicks
on;
the Reset
positions
is the
point
where
the switch
clicks
off.
This
relationship
will
usually be upset
if
the
snapswitch
is replaced,
but
is
easily
restored
as
follows:
1. Remove
knob, front
cover,
and
dial.
Use
care tn
removing dial
so as
not
to deform
pointers.
2.
Bring the set
pointer
(B)
into
alignment with
indicating
pointer
(C).
3. Adjust hex
head screw
(D)to
a
position
midway
between the
two
positions where
the switch
clicks.
4. Check
the setting
by
placing a screwdriver
under
lever
(F)and
simulatlng
tempelatule
changes
by
movement
of
this
lever.
5.
If necessary,
trim
the
setting
by sltght
readjustment of screw
(D)
a
t
SER|ES
400
J{
-ì
s-/